HETEROCYCLIC COMPOUND, ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE HETEROCYCLIC COMPOUND, AND ELECTRONIC APPARATUS INCLUDING THE ORGANIC LIGHT-EMITTING DEVICE

Abstract

Provided are a heterocyclic compound represented by Formula 1-1 or 1-2, an organic light-emitting device including the heterocyclic compound, and an electronic apparatus including the organic light-emitting device:

##STR00001## wherein Formulae 1-1 and 1-2 are respectively the same as described in the present specification.

Claims

1. A heterocyclic compound represented by Formula 1-1 or 1-2: Formula 1-1 ##STR02915## wherein, in Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 are each independently a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group, X.sub.11 to X.sub.16 are each independently a group represented by Formula 2-1 or 2-2, n11 to n16 are each independently 0, 1, or 2, the sum of n11 to n16 in Formula 1-1 is 1 or more, and the sum of n11 to n15 in Formula 1-2 is 1 or more, Y.sub.11 to Y.sub.16 are each independently a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, or a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, m11 to m16 are each independently 0, 1, or 2, the sum of n11 to n16 and m11 to m16 in Formula 1-1 are each 2 or more, and the sum of n11 to n15 and m11 to m15 in Formula 1-2 are each 2 or more, Z.sub.11 to Z.sub.16 are each independently a carbon atom, and a bond between Z.sub.11 and Z.sub.12, a bond between Z.sub.13 and Z.sub.14, and a bond between Z.sub.15 and Z.sub.16 are each independently a single bond or a double bond, ##STR02916## wherein, in Formulae 2-1 and 2-2, X.sub.21 is a single bond, O, S, N(R.sub.25), or C(R.sub.25)(R.sub.26), L.sub.21 and L.sub.22 are each independently a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group, a21 and a22 are each independently 0, 1, or 2, R.sub.21 and R.sub.22 are each independently a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, R.sub.11 to R.sub.18 and R.sub.23 to R.sub.26 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkylheteroaryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryloxy group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —B(Q.sub.1)(Q.sub.2), —N(Q.sub.1)(Q.sub.2), —P(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), —P(═O)(Q.sub.1)(Q.sub.2), or —P(═S)(Q.sub.1)(Q.sub.2), b11 to b16 are each independently 0, 1, 2, or 3, b23 and b24 are each independently 0, 1, 2, 3, or 4, Q.sub.1 to Q.sub.3 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkylheteroaryl group, a C.sub.1-C.sub.60 heteroaryloxy group, a C.sub.1-C.sub.60 heteroarylthio group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C.sub.1-C.sub.6 alkyl group that is substituted with at least one deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof, or a C.sub.6-C.sub.60 aryl group that is substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof, and * indicates a binding site to a neighboring atom.

2. The heterocyclic compound of claim 1, wherein the heterocyclic compound is represented by one of Formulae 1-111 and 1-211: ##STR02917## wherein, in Formulae 1-111 and 1-211, R.sub.110 to R.sub.114 are each independently X.sub.11, Y.sub.11, or R.sub.11, R.sub.121 to R.sub.124 are each independently X.sub.12, Y.sub.12, or R.sub.12, R.sub.131 to R.sub.133 are each independently X.sub.13, Y.sub.13, or R.sub.13, R.sub.141 to R.sub.143 are each independently X.sub.14, Y.sub.14, or R.sub.14, R.sub.151 to R.sub.154 are each independently X.sub.15, Y.sub.15, or R.sub.15, R.sub.161 to R.sub.164 are each independently X.sub.16, Y.sub.16, or R.sub.16, at least one of R.sub.110 to R.sub.114, R.sub.121 to R.sub.124, R.sub.131 to R.sub.133, R.sub.141 to R.sub.143, and R.sub.151 to R.sub.154 is X.sub.11, X.sub.12, X.sub.13, X.sub.14, or X.sub.15, at least two of R.sub.110 to R.sub.114, R.sub.121 to R.sub.124, R.sub.131 to R.sub.133, R.sub.141 to R.sub.143, and R.sub.151 to R.sub.154 are X.sub.11, X.sub.12, X.sub.13, X.sub.14, X.sub.15, Y.sub.11, Y.sub.12, Y.sub.13, Y.sub.14, or Y.sub.15, and X.sub.11 to X.sub.16, Y.sub.11 to Y.sub.16, and R.sub.11 to R.sub.18 are respectively the same as described in claim 1.

3. The heterocyclic compound of claim 1, wherein X.sub.11 to X.sub.16 are each independently a group represented by Formula 2-11 or 2-21: ##STR02918## wherein, in Formulae 2-11 and 2-21, L.sub.21 and L.sub.22 are respectively the same as described in claim 1, a21 and a22 are each independently 0 or 1, and R.sub.201 to R.sub.218 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, or a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group.

4. The heterocyclic compound of claim 1, wherein X.sub.11 to X.sub.16 are each independently represented by one of Formulae 2-111 to 2-122: ##STR02919## ##STR02920## wherein, in Formulae 2-111 to 2-122, t-Bu represents a tert-butyl group, and * indicates a binding site to a neighboring atom.

5. The heterocyclic compound of claim 1, wherein Y.sub.11 to Y.sub.16 are each independently a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, or a chrysenyl group, each substituted or unsubstituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterated C.sub.2-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantanyl group, a (C.sub.1-C.sub.20 alkyl)norbornanyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20)cyclopentenyl group, a (C.sub.1-C.sub.20)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, or any combination thereof.

6. The heterocyclic compound of claim 1, wherein the sum of n11 to n15 in Formulae 1-1 and 1-2 is 1 or 2.

7. The heterocyclic compound of claim 1, wherein the sum of m11 to m16 in Formula 1-1 is 1 or more, and the sum of m11 to m15 in Formula 1-2 is 1 or more.

8. The heterocyclic compound of claim 1, wherein, in Formulae 1-1 and 1-2, the sum of n11 to n15 and m11 to m15 are 2, 3, 4, or 5.

9. The heterocyclic compound of claim 1, wherein the heterocyclic compound is represented by one of Formulae 1-11 to 1-24 and 1-31 to 1-44: ##STR02921## ##STR02922## ##STR02923## ##STR02924## ##STR02925## ##STR02926## ##STR02927## ##STR02928## wherein, in Formulae 1-11 to 1-24 and 1-31 to 1-44, A.sub.11 to A.sub.16, X.sub.11 to X.sub.16, Y.sub.11 to Y.sub.16, Z.sub.11 to Z.sub.16, R.sub.11 to R.sub.18, and b11 to b16 are respectively the same as described in claim 1, n11 to n15 are each independently 1 or 2, m11 to m15 are each independently 0, 1, or 2, and the sum of n11 to n15 and m11 to m15 are 2 or more.

10. The heterocyclic compound of claim 1, wherein the heterocyclic compound is of Compounds 1 to 78: ##STR02929## ##STR02930## ##STR02931## ##STR02932## ##STR02933## ##STR02934## ##STR02935## ##STR02936## ##STR02937## ##STR02938## ##STR02939## ##STR02940## ##STR02941## ##STR02942## ##STR02943## ##STR02944## ##STR02945## ##STR02946## ##STR02947## ##STR02948## ##STR02949## ##STR02950## ##STR02951## ##STR02952## ##STR02953## ##STR02954## ##STR02955##

11. An organic light-emitting device comprising: a first electrode; a second electrode; and an organic layer arranged between the first electrode and the second electrode and comprising an emission layer, wherein the organic layer comprises the heterocyclic compound of claim 1.

12. The organic light-emitting device of claim 11, wherein the emission layer comprises the heterocyclic compound.

13. The organic light-emitting device of claim 12, wherein the emission layer further comprises a host and an emitter, the host and the emitter are different from each other, and the emitter comprises the heterocyclic compound.

14. The organic light-emitting device of claim 13, wherein the emission layer emits blue light.

15. The organic light-emitting device of claim 13, wherein the emitter is a fluorescent emitter and/or a delayed fluorescence emitter.

16. The organic light-emitting device of claim 12, wherein the emission layer further comprises a host, an emitter, and a sensitizer, the host, the emitter, and the sensitizer are different from each other, and the emitter comprises the heterocyclic compound.

17. The organic light-emitting device of claim 16, wherein the emission layer emits blue light.

18. The organic light-emitting device of claim 16, wherein the emitter is a fluorescent emitter and/or a delayed fluorescence emitter.

19. The organic light-emitting device of claim 16, wherein the sensitizer and the heterocyclic compound satisfy Condition 5:
0 μs<T.sub.decay(HC)<5 μs  Condition 5 wherein, in Condition 5, T.sub.decay(HC) indicates a decay time of the heterocyclic compound.

20. An electronic apparatus comprising the organic light-emitting device of claim 11.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0030] FIG. 1 shows a schematic cross-sectional view of an organic light-emitting device according to an exemplary embodiment;

[0031] FIG. 2 is a schematic cross-sectional view of an organic light-emitting device according to another exemplary embodiment;

[0032] FIG. 3 is a schematic cross-sectional view of an organic light-emitting device according to another exemplary embodiment; and

[0033] FIGS. 4A to 4E are each diagram illustrating energy levels in an emission layer of an organic light-emitting device according to an exemplary embodiment.

DETAILED DESCRIPTION

[0034] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout the specification. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects. As used herein, the term “and/or” includes any and all combinations of one or more of the same associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

[0035] It will be understood that when an element is referred to as being “on” another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present

[0036] It will be understood that, although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section Thus, “a first element,” “component,” “region,” “layer” or “section” discussed below could be termed a second element, component, region, layer or section without departing from the teachings herein.

[0037] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, “a,” “an,” “the,” and “at least one” do not denote a limitation of quantity, and are intended to cover both the singular and plural, unless the context clearly indicates otherwise. For example, “an element” has the same meaning as “at least one element,” unless the context clearly indicates otherwise.

[0038] “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

[0039] Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top,” may be used herein to describe one element's relationship to another element as illustrated in the Figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures For example, if the device in one of the figures is turned over, elements described as being on the “lower” side of other elements would then be oriented on “upper” sides of the other elements The exemplary term “lower,” can therefore, encompasses both an orientation of “lower” and “upper,” depending on the particular orientation of the figure. Similarly, if the device in one of the figures is turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below.

[0040] “About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±30%, 20%, 10% or 5% of the stated value.

[0041] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0042] Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.

[0043] An aspect of the present disclosure provides a heterocyclic compound represented by Formula 1-1 or 1-2:

##STR00004##

[0044] In Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 may each independently be a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group.

[0045] In an embodiment, in Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 may each independently be a benzene group, a naphthalene group, a phenanthrene group, a furan group, a thiophene group, a pyrrole group, a cyclopentene group, a silole group, a germole group, a benzofuran group, a benzothiophene group, an indole group, an indene group, a benzosilole group, a benzogermole group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, a fluorene group, a dibenzosilole group, or a dibenzogermole group.

[0046] In one or more embodiments, in Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 may each independently be a benzene group, a naphthalene group, a benzofuran group, a benzothiophene group, an indole group, an indene group, a benzosilole group, or a benzogermole group.

[0047] In one or more embodiments, in Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 may each independently be a benzene group or a naphthalene group.

[0048] In one or more embodiments, in Formulae 1-1 and 1-2, A.sub.11 to A.sub.16 may each independently be a benzene group.

[0049] In an embodiment, in Formulae 1-1 and 1-2, X.sub.11 to X.sub.16 may each independently be a group represented by Formula 2-1 or 2-2:

##STR00005##

[0050] In Formulae 2-1 and 2-2,

[0051] X.sub.21 may be a single bond, O, S, N(R.sub.25), or C(R.sub.25)(R.sub.26),

[0052] L.sub.21 and L.sub.22 may each independently be a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group,

[0053] a21 and a22 may each independently be 0, 1, or 2,

[0054] R.sub.21 and R.sub.22 may each independently be a substituted or unsubstituted C.sub.6-C.sub.60 aryl group,

[0055] R.sub.23 to R.sub.26 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkylheteroaryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryloxy group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —B(Q.sub.1)(Q.sub.2), —N(Q.sub.1)(Q.sub.2), —P(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), —P(═O)(Q.sub.1)(Q.sub.2), or —P(═S)(Q.sub.1)(Q.sub.2),

[0056] Q.sub.1 to Q.sub.3 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkylheteroaryl group, a C.sub.1-C.sub.60 heteroaryloxy group, a C.sub.1-C.sub.60 heteroarylthio group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C.sub.1-C.sub.6 alkyl group that is substituted with at least one deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, and a C.sub.6-C.sub.60 aryl group, and a C.sub.6-C.sub.60 aryl group that is substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, or a C.sub.6-C.sub.60 aryl group,

[0057] b23 and b24 may each independently be 0, 1, 2, 3, or 4, and

[0058] * indicates a binding site to a neighboring atom.

[0059] In an embodiment, in Formula 2-2, X.sub.21 may be a single bond.

[0060] In an embodiment, in Formulae 2-1 and 2-2, L.sub.21 and L.sub.22 may each independently be a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group.

[0061] In an embodiment, in Formulae 2-1 and 2-2, a21 and a22 may each independently be 0 or 1.

[0062] In an embodiment, in Formula 2-1, R.sub.21 and R.sub.22 may each independently be a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a phenanthrenyl group, an anthracenyl group, a triphenylenyl group, a pyrenyl group, or a chrysenyl group, each substituted or unsubstituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterated C.sub.2-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantanyl group, a (C.sub.1-C.sub.20 alkyl)norbornanyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl) cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, or any combination thereof.

[0063] In one or more embodiments, in Formula 2-1, R.sub.21 and R.sub.22 may each independently be hydrogen, deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a C.sub.2-C.sub.10 alkenyl group, a C.sub.1-C.sub.10 alkoxy group, a C.sub.1-C.sub.10 alkylthio group, a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130, a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130 in which at least one hydrogen is substituted with deuterium group, or a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130 in which at least one hydrogen is substituted with —F:

##STR00006## ##STR00007## ##STR00008## ##STR00009## ##STR00010## ##STR00011## ##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020##

[0064] In Formulae 10-12 to 10-23 and 10-38 to 10-130,

[0065] “Ph” represents a phenyl group, and

[0066] * indicates a binding site to a neighboring atom.

[0067] In an embodiment, in Formula 2-2, R.sub.23 to R.sub.26 may each independently be:

[0068] hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, —SF.sub.5, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkenyl group, a C.sub.1-C.sub.20 alkoxy group, or a C.sub.1-C.sub.20 alkylthio group;

[0069] a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkenyl group, a C.sub.1-C.sub.20 alkoxy group, or a C.sub.1-C.sub.20 alkylthio group, each substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantanyl group, a (C.sub.1-C.sub.20 alkyl)norbornanyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof;

[0070] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, or an azadibenzothiophenyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterated C.sub.2-C.sub.20 alkyl group, a fluorinated alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantanyl group, a (C.sub.1-C.sub.20 alkyl)norbornanyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, or any combination thereof; or

[0071] —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —B(Q.sub.1)(Q.sub.2), or —N(Q.sub.1)(Q.sub.2), and

[0072] Q.sub.1 to Q.sub.3 may each independently be:

[0073] deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CH.sub.2CH.sub.3, —CH.sub.2CD.sub.3, —CH.sub.2CD.sub.2H, —CH.sub.2CDH.sub.2, —CHDCH.sub.3, —CHDCD.sub.2H, —CHDCDH.sub.2, —CHDCD.sub.3, —CD.sub.2CD.sub.3, —CD.sub.2CD.sub.2H, —CD.sub.2CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, —CH.sub.2CF.sub.3, —CH.sub.2CF.sub.2H, —CH.sub.2CFH.sub.2, —CHFCH.sub.3, —CHFCF.sub.2H, —CHFCFH.sub.2, —CHFCF.sub.3, —CF.sub.2CF.sub.3, —CF.sub.2CF.sub.2H, or —CF.sub.2CFH.sub.2; or

[0074] an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, a phenyl group, a biphenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.10 alkyl group, a phenyl group, or any combination thereof.

[0075] In one or more embodiments, in Formula 2-2, R.sub.23 to R.sub.26 may each independently be hydrogen, deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a C.sub.2-C.sub.10 alkenyl group, a C.sub.1-C.sub.10 alkoxy group, a C.sub.1-C.sub.10 alkylthio group, a group represented by one of Formulae 9-1 to 9-39, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 9-201 to 9-236, a group represented by one of Formulae 9-201 to 9-236 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 9-201 to 9-236 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-1 to 10-130, a group represented by one of Formulae 10-1 to 10-130 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-1 to 10-130 in which at least one hydrogen is substituted with —F, a group represented by one of Formulae 10-201 to 10-358, a group represented by one of Formulae 10-201 to 10-358 in which at least one hydrogen is substituted with deuterium, a group represented by one of Formulae 10-201 to 10-358 in which at least one hydrogen is substituted with —F, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), or —Ge(Q.sub.1)(Q.sub.2)(Q.sub.3), and

[0076] Q.sub.1 to Q.sub.3 may each independently be:

[0077] deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CH.sub.2CH.sub.3, —CH.sub.2CD.sub.3, —CH.sub.2CD.sub.2H, —CH.sub.2CDH.sub.2, —CHDCH.sub.3, —CHDCD.sub.2H, —CHDCDH.sub.2, —CHDCD.sub.3, —CD.sub.2CD.sub.3, —CD.sub.2CD.sub.2H, —CD.sub.2CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, —CH.sub.2CF.sub.3, —CH.sub.2CF.sub.2H, —CH.sub.2CFH.sub.2, —CHFCH.sub.3, —CHFCF.sub.2H, —CHFCFH.sub.2, —CHFCF.sub.3, —CF.sub.2CF.sub.3, —CF.sub.2CF.sub.2H, or —CF.sub.2CFH.sub.2; or

[0078] an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, a phenyl group, a biphenyl group, or a naphthyl group, each unsubstituted or substituted with deuterium, —F, a C.sub.1-C.sub.10 alkyl group, a phenyl group, or any combination thereof:

##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045##

##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059##

[0079] In Formulae 9-1 to 9-39, 9-201 to 9-236, 10-1 to 10-130, and 10-201 to 10-358, * indicates a binding site to a neighboring atom, Ph represents a phenyl group, TMS and SiMe.sub.3 each represent a trimethylsilyl group, and TMG and GeMe.sub.3 each represent a trimethylgermyl group.

[0080] The “group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with deuterium” and the “group represented by one of Formulae 9-201 to 9-236 in which at least one hydrogen is substituted with deuterium” may each independently be, for example, a group represented by one of Formulae 9-501 to 9-514 and 9-601 to 9-636:

##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065##

[0081] The “group represented by one of Formulae 9-1 to 9-39 in which at least one hydrogen is substituted with —F” and the “group represented by one of Formulae 9-201 to 9-236 in which at least one hydrogen is substituted with —F” may each independently be, for example, a group represented by one of Formulae 9-701 to 9-710:

##STR00066##

[0082] The “group in which at least one hydrogen of one of Formulae 10-1 to 10-130 is substituted with deuterium” and “the group in which at least one hydrogen of one of Formulae 10-201 to 10-358 is substituted with deuterium” may each independently be, for example, a group represented by one of Formulae 10-501 to 10-576:

##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078##

[0083] The “group in which at least one hydrogen of one of Formulae 10-1 to 10-130 is substituted with —F” and “the group in which at least one hydrogen of one of Formulae 10-201 to 10-358 is substituted with —F” may each independently be, for example, a group represented by one of Formulae 10-601 to 10-617:

##STR00079## ##STR00080##

[0084] In an embodiment, in Formulae 1-1 and 1-2, X.sub.11 to X.sub.16 may each independently be a group represented by Formula 2-11 or 2-21:

##STR00081##

[0085] In Formulae 2-11 and 2-21,

[0086] L.sub.21 and L.sub.22 may respectively be the same as described herein,

[0087] a21 and a22 may each independently be 0 or 1, and

[0088] R.sub.201 to R.sub.218 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, or a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group.

[0089] In one or more embodiments, in Formulae 1-1 and 1-2, X.sub.11 to X.sub.16 may each independently be represented by one of Formulae 2-111 to 2-122:

##STR00082## ##STR00083##

[0090] In Formulae 2-111 to 2-122,

[0091] t-Bu represents a tert-butyl group, and

[0092] * indicates a binding site to a neighboring atom.

[0093] In Formulae 1-1 and 1-2, n11 to n16 may each independently be 0, 1, or 2. Here, n11 to n16 indicate the number of substitutions, X.sub.11 to X.sub.16, respectively.

[0094] The sum of n11 to n16 in Formula 1-1 may be 1 or more, and the sum of n11 to n15 in Formula 1-2 may be 1 or more.

[0095] In an embodiment, the sum of n11 to n15 in Formula 1-1 may be 1 or more.

[0096] In an embodiment, the sum of n11 to n15 in Formulae 1-1 and 1-2 may be 1 or 2.

[0097] In an embodiment, in Formulae 1-1 and 1-2, Y.sub.11 to Y.sub.16 may each independently be a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, or a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group.

[0098] In one or more embodiments, in Formulae 1-1 and 1-2, Y.sub.11 to Y.sub.16 may each independently be a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, or a chrysenyl group, each substituted or unsubstituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a deuterated C.sub.2-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, a bicyclo[2.2.2]octyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptyl group, a (C.sub.1-C.sub.20 alkyl)cyclooctyl group, a (C.sub.1-C.sub.20 alkyl)adamantanyl group, a (C.sub.1-C.sub.20 alkyl)norbornanyl group, a (C.sub.1-C.sub.20 alkyl)norbornenyl group, a (C.sub.1-C.sub.20 alkyl)cyclopentenyl group, a (C.sub.1-C.sub.20 alkyl)cyclohexenyl group, a (C.sub.1-C.sub.20 alkyl)cycloheptenyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[1.1.1]pentyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.1.1]hexyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.1]heptyl group, a (C.sub.1-C.sub.20 alkyl)bicyclo[2.2.2]octyl group, a phenyl group, a (C.sub.1-C.sub.20 alkyl)phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, or any combination thereof.

[0099] In one or more embodiments, in Formulae 1-1 and 1-2, Y.sub.11 to Y.sub.16 may each independently be hydrogen, deuterium, —F, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a C.sub.2-C.sub.10 alkenyl group, a C.sub.1-C.sub.10 alkoxy group, a C.sub.1-C.sub.10 alkylthio group, a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130, a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130 in which at least one hydrogen is substituted with deuterium group, or a group represented by one of Formulae 10-12 to 10-23 and 10-38 to 10-130 in which at least one hydrogen is substituted with —F:

##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096## ##STR00097## ##STR00098##

[0100] In Formulae 10-12 to 10-23 and 10-38 to 10-130,

[0101] “Ph” represents a phenyl group, and

[0102] * indicates a binding site to a neighboring atom.

[0103] In Formulae 1-1 and 1-2, m11 to m16 may each independently be 0, 1, or 2. In Formulae 1-1 and 1-2, m11 to m16 indicate the number of substituents, Y.sub.11 to Y.sub.16, respectively.

[0104] In an embodiment, the sum of m11 to m16 in Formula 1-1 may be 1 or more, and the sum of m11 to m15 in Formula 1-2 may be 1 or more.

[0105] In one or more embodiments, in Formulae 1-1 and 1-2, the sum of m11 to m15 may be 1 or more.

[0106] In one or more embodiments, in Formulae 1-1 and 1-2, m11 to m15 may each independently be 1 or 2.

[0107] In Formula 1-1, the sum of n11 to n16 and m11 to m16 may be 2 or more. In Formula 1-2, the sum of n11 to n15 and m11 to m15 may be 2 or more.

[0108] In an embodiment, in Formulae 1-1 and 1-2, the sum of n11 to n15 and m11 to m15 may be 2, 3, 4, or 5.

[0109] In one or more embodiments, in Formulae 1-1 and 1-2, the sum of n11 to n15 and m11 to m15 may be 4 or 5.

[0110] In Formulae 1-1 and 1-2, Z.sub.11 to Z.sub.16 may each independently be a carbon atom, and a bond between Z.sub.11 and Z.sub.12, a bond between Z.sub.13 and Z.sub.14, and a bond between Z.sub.15 and Z.sub.16 may each independently be a single bond or a double bond.

[0111] In Formulae 1-1 and 1-2, R.sub.11 to R.sub.1, may each independently be the same as described in connection with R.sub.23.

[0112] In Formulae 1-1 and 1-2, b11 to b16 may each independently be 0, 1, 2, or 3. In Formulae 1-1 and 1-2, b11 to b16 indicate the number of substituents, R.sub.11 to R.sub.16, respectively.

[0113] In an embodiment, the heterocyclic compound may be represented by one of Formulae 1-111 and 1-211:

##STR00099##

[0114] In Formulae 1-111 and 1-211,

[0115] R.sub.110 to R.sub.114 may each independently be X.sub.11, Y.sub.11, or R.sub.11,

[0116] R.sub.121 to R.sub.124 may each independently be X.sub.12, Y.sub.12, or R.sub.12,

[0117] R.sub.131 to R.sub.133 may each independently be X.sub.13, Y.sub.13, or R.sub.13,

[0118] R.sub.141 to R.sub.143 may each independently be X.sub.14, Y.sub.14, or R.sub.14,

[0119] R.sub.151 to R.sub.154 may each independently be X.sub.15, Y.sub.15, or R.sub.15,

[0120] R.sub.161 to R.sub.164 may each independently be X.sub.16, Y.sub.16, or R.sub.16,

[0121] at least one of R.sub.110 to R.sub.114, R.sub.121 to R.sub.124, R.sub.131 to R.sub.133, R.sub.141 to R.sub.143, and R.sub.151 to R.sub.154 may be X.sub.11, X.sub.12, X.sub.13, X.sub.14, or X.sub.15,

[0122] at least two of R.sub.110 to R.sub.114, R.sub.121 to R.sub.124, R.sub.131 to R.sub.133, R.sub.141 to R.sub.143, and R.sub.151 to R.sub.154 may each independently be X.sub.11, X.sub.12, X.sub.13, X.sub.14, X.sub.15, Y.sub.11, Y.sub.12, Y.sub.13, Y.sub.14, or Y.sub.15, and

[0123] X.sub.11 to X.sub.16, Y.sub.11 to Y.sub.16, and R.sub.11 to R.sub.18 may respectively be the same as described in connection with Formulae 1-1 and 1-2.

[0124] In one or more embodiments, the heterocyclic compound may be represented by one of Formulae 1-11 to 1-24 and 1-31 to 1-44:

##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105##

[0125] In Formulae 1-11 to 1-24 and 1-31 to 1-44,

[0126] A.sub.11 to A.sub.16, X.sub.11 to X.sub.16, Y.sub.11 to Y.sub.16, Z.sub.11 to Z.sub.16, R.sub.11 to R.sub.18, and b11 to b16 may respectively be the same as described in connection with Formulae 1-1 and 1-2,

[0127] n11 to n15 may each independently be 1 or 2,

[0128] m11 to m15 may each independently be 0, 1, or 2, and

[0129] the sum of n11 to n15 and m11 to m15 may be 2 or more.

[0130] For example, in Formulae 1-11 to 1-24 and 1-31 to 1-44, A.sub.11 to A.sub.16 may each independently be a benzene group.

[0131] For example, in Formulae 1-11 to 1-24 and 1-31 to 1-44, the sum of m11 to m15 may be 1 or more.

[0132] For example, in Formulae 1-11 to 1-24 and 1-31 to 1-44, m11 to m15 may each independently be 1 or 2.

[0133] For example, in Formulae 1-11 to 1-24 and 1-31 to 1-44, the sum of n11 to n15 and m11 to m15 may each independently be 4 or 5.

[0134] In one or more embodiments, the heterocyclic compound may be of Compounds 1 to 78:

##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116## ##STR00117## ##STR00118## ##STR00119## ##STR00120## ##STR00121## ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133##

[0135] Since the heterocyclic compound has a rigid structure in which aromatic hydrocarbon rings or heteroaromatic rings are condensed with each other, structural relaxation in an excited state may be suppressed. As a result, the heterocyclic compound may have a narrow width of blue emission spectrum and exhibit improved color purity.

[0136] In detail, since the heterocyclic compound includes an N atom in a moiety structure represented by

##STR00134##

then the heterocyclic compound may have a relatively narrow full width at half maximum (FWHM), and more specifically, may have a narrower FWHM than that of a heterocyclic compound including an O atom or an S atom. For example, it is known that a FWHM of each of TMCz-BO and TMCz-3P that include an O atom or an S atom is 59 nm and 61 nm, respectively (J. U. Kim, I. S. Park, C.-Y. Chan, M. Tanaka, Y. Tsuchiya, H. Nakanotani, C. Adachi, Nat. Commun. 2020, 11, 1765), but a FWHM of TBN-TPA including an N atom with relatively low structural fluidity is 27 nm (X. Liang, Z.-P. Yan, H.-B. Han, Z.-G. Wu, Y.-X. Zheng, H. Meng, J.-L. Zuo, W. Huang, Angew. Chem., Int. Ed. 2018, 57, 11316).

[0137] In addition, in the heterocyclic compound of the present disclosure, the sum of n11 to n16 in Formula 1-1 may be 1 or more, and the sum of n11 to n15 in Formula 1-2 may be 1 or more. In this regard, the heterocyclic compound may have improved luminescence efficiency, and as compared to a compound including an alkylamino group or the like, the heterocyclic compound has a substituent in which an aryl group is substituted for N so that the compound stability may be improved. Accordingly, an organic light-emitting device including the heterocyclic compound may have improved efficiency and/or a long lifespan.

[0138] In the heterocyclic compound, the sum of n11 to n16 and m11 to m16 in Formula 1-1 may each be 2 or more, and the sum of n11 to n15 and m11 to m15 in Formula 1-2 may each be 2 or more. In this regard, due to the extended conjugated bonds in the heterocyclic compound, stabilization of the heterocyclic compound may be achieved. Accordingly, an organic light-emitting device including the heterocyclic compound may have improved efficiency and/or a long lifespan.

[0139] In addition, since the heterocyclic compound has an asymmetric structure in its core, a dense wavelength control may be possible along with shortening of an emission wavelength, thereby providing an organic light emitting device with high efficiency and/or a long life.

[0140] A peak wavelength in photoluminescence (PL) of the heterocyclic compound according to an embodiment is not particularly limited, but may be about 430 nm or more. In one or more embodiments, the peak wavelength may be about 435 nm or more, about 440 nm or more, about 500 nm or less, about 490 nm or less, or about 480 nm or less. When the peak wavelength is within these ranges, the heterocyclic compound according to an embodiment may be particularly suitable for emission of blue light.

[0141] The heterocyclic compound according to an embodiment may have a small FWHM value of an emission intensity of a peak having the PL peak wavelength above. In detail, the heterocyclic compound may have a FWHM value of about 45 nm or less, about 40 nm or less, or about 35 nm or less. When the FWHM is within these ranges, the heterocyclic compound according to an embodiment may have further improved color purity.

[0142] The peak wavelength and the FWHM in the PL may each be measured and/or calculated using a spectrofluorophotometer.

[0143] A highest occupied molecular orbital (HOMO) energy level, a lowest unoccupied molecular orbital (LUMO) energy level, an S.sub.1 energy level, and a T.sub.1 energy level of some compounds of the heterocyclic compound represented by Formula 1-1 or 1-2 are evaluated using the Gaussian 09 program with the molecular structure optimization obtained by B3LYP-based density functional theory (DFT), and results thereof are shown in Table 1.

TABLE-US-00001 TABLE 1 Compound No. HOMO (eV) LUMO (eV) S.sub.1 (eV) T.sub.1 (eV) 1 −5.04 −1.57 2.99 2.58 6 −4.96 −1.49 3.00 2.62 8 −4.81 −1.34 3.00 2.65 10 −5.15 −1.68 3.00 2.61 13 −5.00 −1.51 3.01 2.65

##STR00135## ##STR00136##

[0144] Referring to Table 1, it is confirmed that the heterocyclic compound represented by Formula 1-1 or 1-2 has electric characteristics suitable for use as a dopant in an emission layer of an electronic device, for example, an organic light-emitting device.

[0145] Synthesis methods of the heterocyclic compound according to an embodiment is not particularly limited, and the heterocyclic compound may be synthesized according to a known synthesis method. In particular, the heterocyclic compound may be synthesized according to or in view of methods described in Examples below. For example, in the methods described in Examples below, the heterocyclic compound according to an embodiment may be synthesized through modifications such as changing raw materials and reaction conditions, adding or excluding some processes, or appropriately combining with other known synthesis methods.

[0146] A method of identifying a structure of the heterocyclic compound according to an embodiment is not particularly limited. The heterocyclic compound including nitrogen according to an embodiment may be identified by a known method (for example, NMR, LC-MS, or the like).

Description of FIG. 1

[0147] FIG. 1 is a schematic view of an organic light-emitting device 10 according to an exemplary embodiment. Hereinafter, a structure and a manufacturing method of an organic light-emitting device according to an example of the present disclosure will be described with reference to FIG. 1.

[0148] The organic light-emitting device 10 of FIG. 1 includes a first electrode 11, a second electrode 19 facing the first electrode 11, and an organic layer 10A between the first electrode 11 and the second electrode 19.

[0149] The organic layer 10A may include an emission layer 15, a hole transport region 12 may be arranged between the first electrode 11 and the emission layer 15, and an electron transport region 17 may be arranged between the emission layer 15 and the second electrodes 19.

[0150] A substrate may be additionally arranged under the first electrode 11 or above the second electrode 19. For use as the substrate, any substrate that is used in organic light-emitting devices available in the art may be used, and the substrate may be a glass substrate or a transparent plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

[First Electrode 11]

[0151] The first electrode 11 may be, for example, formed by depositing or sputtering a material for forming the first electrode 11 on the substrate. The first electrode 11 may be an anode. The material for forming the first electrode 11 may be a material with a high work function to facilitate hole injection.

[0152] The first electrode 11 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. In an embodiment, when the first electrode 11 is a transmissive electrode, the material for forming the first electrode 11 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), zinc oxide (ZnO), or any combination thereof, but embodiments of the present disclosure are not limited thereto. In one or more embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, the material for forming the first electrode 11 may be magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof, but embodiments of the present disclosure are not limited thereto.

[0153] The first electrode 11 may have a single-layered structure or a multi-layered structure including two or more layers.

[Emission Layer 15]

[0154] The emission layer 15 may include the heterocyclic compound.

[0155] A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within these ranges, excellent luminescence characteristics may be obtained without a substantial increase in driving voltage.

First Embodiment—Descriptions of FIG. 4A

[0156] In the First Embodiment, the heterocyclic compound may be a fluorescence emitter. According to the First Embodiment, the emission layer may further include a host (hereinafter, referred to as ‘Host A’ which is not identical to the heterocyclic compound). Host A may be understood by referring to a host material described below, but embodiments are not limited thereto. Host A may be a fluorescent host.

[0157] FIG. 4A depicts the general energy transfer of the First Embodiment.

[0158] Singlet excitons may be generated in Host A included in the emission layer, and these singlet excitons may be transferred to a fluorescence emitter through Förster energy transfer (FRET).

[0159] Since the singlet excitons generated in Host A accounts for only 25% of the total excitons, triplet excitons which accounts for 75% of the total excitons may be fused to one another to be converted into singlet excitons. Accordingly, efficiency of the organic light-emitting device may be further improved. That is, by using a triplet-triplet fusion mechanism, the efficiency of the organic light-emitting device may be further improved.

[0160] According to the First Embodiment, emission components emitted from the heterocyclic compound may account for about 80% or more, for example, about 90% or more, of the total emission components emitted from the emission layer. For example, emission components emitted from the heterocyclic compound may account for about 95% or more of the total emission components emitted from the emission layer.

[0161] Here, the heterocyclic compound may emit fluorescence, and the host may not emit light.

[0162] In the First Embodiment, when the emission layer further includes Host A in addition to the heterocyclic compound, an amount of the heterocyclic compound may be about 50 parts by weight or less, for example, about 30 parts by weight or less, based on 100 parts by weight of the emission layer, and an amount of Host A in the emission layer may be about 50 parts by weight or more, for example, about 70 parts by weight or more, based on 100 parts by weight of the emission layer. However, embodiments of the present disclosure are not limited thereto.

[0163] In the First Embodiment, when the emission layer further includes Host A in addition to the heterocyclic compound, Host A and the heterocyclic compound may satisfy Condition A:

E(H.sub.A).sub.S1>E.sub.S1  Condition A

[0164] wherein, in Condition A,

[0165] E(H.sub.A).sub.S1 indicates a lowest excited singlet energy level of Host A, and

[0166] E.sub.S1 indicates a lowest excited singlet energy level of the heterocyclic compound.

[0167] Here, E(H.sub.A).sub.S1 and E.sub.S1 may be evaluated using the DFT method of the Gaussian program with structure optimization performed at a degree of B3LYP/6-31G(d,p).

Second Embodiment—Descriptions of FIG. 4B

[0168] In the Second Embodiment, the heterocyclic compound may be a delayed fluorescence emitter. According to the Second Embodiment, the emission layer may further include a host (hereinafter, referred to as ‘Host B’ which is not identical to the heterocyclic compound). Host B may be understood by referring a host material described below, but embodiments are not limited thereto.

[0169] FIG. 4B depicts the general energy transfer of the Second Embodiment.

[0170] Singlet excitons generated at a ratio of 25% in Host B included in the emission layer may be transferred to a delayed fluorescence emitter through FRET. In addition, triplet excitons generated at a ratio of 75% in Host B included in the emission layer may be transferred to a delayed fluorescence emitter through Dexter energy transfer. The energy transferred to a triplet state of the delayed fluorescence emitter may undergo reverse intersystem crossing (RISC) to a singlet state. Accordingly, by transferring all the singlet excitons and triplet excitons generated in the emission layer to the heterocyclic compound, the organic light-emitting device with improved efficiency may be obtained.

[0171] According to the Second Embodiment, emission components emitted from the heterocyclic compound may account for about 80% or more, for example, about 90% or more, of the total emission components emitted from the emission layer. For example, emission components emitted from the heterocyclic compound may account for about 95% or more of the total emission components emitted from the emission layer.

[0172] Here, the heterocyclic compound may emit fluorescence and/or delayed fluorescence, and the emission components of the heterocyclic compound may be a total of prompt emission components of the heterocyclic compound and delayed fluorescence components by RISC of the heterocyclic compound. In addition, Host B may not emit light.

[0173] In the Second Embodiment, when the emission layer further includes Host B in addition to the heterocyclic compound, an amount of the heterocyclic compound may be about 50 parts by weight or less, for example, about 30 parts by weight or less, based on 100 parts by weight of the emission layer, and an amount of Host B in the emission layer may be about 50 parts by weight or more, for example, about 70 parts by weight or more, based on 100 parts by weight of the emission layer. However, embodiments of the present disclosure are not limited thereto.

[0174] In the Second Embodiment, when the emission layer further includes Host B in addition to the heterocyclic compound, Host B and the heterocyclic compound may satisfy Condition B:

E(H.sub.B).sub.S1>E.sub.S1  Condition B

[0175] wherein, in Condition B,

[0176] E(H.sub.B).sub.S1 indicates a lowest excited singlet energy level of Host B, and

[0177] E.sub.S1 indicates a lowest excited singlet energy level of the heterocyclic compound.

[0178] Here, E(H.sub.B).sub.S1 and E.sub.S1 may be evaluated using the DFT method of the Gaussian program with structure optimization performed at a degree of B3LYP/6-31G(d,p).

Third Embodiment and Fourth Embodiment

Third Embodiment—Descriptions of FIG. 4C

[0179] In the Third Embodiment, the heterocyclic compound may be used as a fluorescent emitter, and the emission layer may include a sensitizer, for example, a delayed fluorescence sensitizer. In the Third Embodiment, the emission layer may further include a host (hereinafter, referred to as ‘Host C’ which is not identical to the heterocyclic compound and the sensitizer) and a sensitizer (hereinafter, referred to as ‘Sensitizer A’ which is not identical to Host C and the heterocyclic compound). Host C and Sensitizer A may respectively be understood by referring to a host material and a sensitizer material described below, but embodiments are not limited thereto.

[0180] According to the Third Embodiment, emission components emitted from the heterocyclic compound may account for about 80% or more, for example, about 90% or more (and for example, about 95% or more), of the total emission components emitted from the emission layer. For example, the heterocyclic compound may emit fluorescence. In addition, Host C and Sensitizer A may not each emit light.

[0181] FIG. 4C depicts the general energy transfer of the Third Embodiment.

[0182] Singlet and triplet excitons may be generated in Host C included in the emission layer, and these singlet and triplet excitons may be transferred to Sensitizer A first, and then to the heterocyclic compound through FRET. The singlet excitons generated at a ratio of 25% in Host C may be transferred to Sensitizer A through FRET, and the energy of triplet excitons generated at a ratio of 75% in Host C may be transferred to a singlet state and a triplet state of Sensitizer A, wherein the energy transferred to the triplet state may undergo RISC to the singlet state, and then, the singlet energy of Sensitizer A may be transferred to the heterocyclic compound through FRET.

[0183] Accordingly, by transferring all the singlet excitons and triplet excitons generated in the emission layer to a dopant, an organic light-emitting device having improved efficiency may be obtained. In addition, since an organic light-emitting device thus obtained has significantly reduced energy loss, lifespan characteristics thereof may be also improved.

[0184] In the Third Embodiment, when the emission layer further includes, in addition to the heterocyclic compound, Host C and Sensitizer A, Host C and Sensitizer A may satisfy Condition C-1 and/or C-2:

S.sub.1(H.sub.C)≥S.sub.1(S.sub.A)  Condition C-1

S.sub.1(S.sub.A)≥S.sub.1(HC)  Condition C-2

[0185] wherein, in Conditions C-1 and C-2,

[0186] S.sub.1(H.sub.C) indicates a lowest excited singlet energy level of Host C,

[0187] S.sub.1(S.sub.A) indicates a lowest excited singlet energy level of Sensitizer A, and

[0188] S.sub.1(HC) indicates a lowest excited singlet energy level of the heterocyclic compound.

[0189] S.sub.1(H.sub.C), S.sub.1(S.sub.A), and S.sub.1(HC) may be evaluated using the DFT method of the Gaussian program with structure optimization performed at a degree of B3LYP/6-31 G(d,p).

[0190] When Host C, Sensitizer A, and the heterocyclic compound satisfy Condition C-1 and/or C-2, FRET from Sensitizer A to the heterocyclic compound may be facilitated, and accordingly, the organic light-emitting device may have improved luminescence efficiency.

Fourth Embodiment—Descriptions of FIG. 4D

[0191] In the Fourth Embodiment, the heterocyclic compound may be used as a fluorescence emitter, and the emission layer may include a sensitizer, for example, a phosphorescence sensitizer. In the Fourth Embodiment, the emission layer may further include a host (hereinafter, referred to as ‘Host D’ which is not identical to the heterocyclic compound and the sensitizer) and a sensitizer (hereinafter, referred to as ‘Sensitizer B’ which is not identical to Host D and the heterocyclic compound). Host D and Sensitizer B may respectively be understood by referring to a host material and a sensitizer material described below, but embodiments are not limited thereto.

[0192] According to the Fourth Embodiment, emission components emitted from the heterocyclic compound may account for about 80% or more, for example, about 90% or more (and for example, about 95% or more), of the total emission components emitted from the emission layer. For example, the heterocyclic compound may emit fluorescence. In addition, Host D and Sensitizer B may not each emit light.

[0193] FIG. 4D depicts the general energy transfer of the Fourth Embodiment.

[0194] Triplet excitons generated at a ratio of 3:1 (i.e., 75%) in Host D included in the emission layer may be transferred to Sensitizer B through Dexter energy transfer, and energy of singlet excitons generated at a ratio of 1:3 (i.e., 25%) in Host D may be transferred to a singlet state and a triplet state of Sensitizer B, wherein the energy transferred to the singlet state of Sensitizer B may undergo ISC to the triplet state, and then, the triplet energy of Sensitizer B may be transferred to the heterocyclic compound through FRET.

[0195] Accordingly, by transferring all the singlet excitons and triplet excitons generated in the emission layer to a dopant, an organic light-emitting device having improved efficiency may be obtained. In addition, since an organic light-emitting device thus obtained has significantly reduced energy loss, lifespan characteristics thereof may be also improved.

[0196] In the Third Embodiment, when the emission layer further includes, in addition to the heterocyclic compound, Host D and Sensitizer B, Host D and Sensitizer B may satisfy Condition D-1 and/or D-2:

T.sub.1(H.sub.D)≥T.sub.1(S.sub.B)  Condition D-1

T.sub.1(S.sub.B)≥S.sub.1(HC)  Condition D-2

[0197] wherein, in Conditions D-1 and D-2,

[0198] T.sub.1(H.sub.D) indicates a lowest excited triplet energy level of Host D,

[0199] T.sub.1(S.sub.B) indicates a lowest excited triplet energy level of Sensitizer B, and

[0200] S.sub.1(HC) indicates a lowest excited singlet energy level of the heterocyclic compound.

[0201] T.sub.1(H.sub.D), T.sub.1(S.sub.B), and S.sub.1(HC) may be evaluated using the DFT method of the Gaussian program with structure optimization performed at a degree of B3LYP/6-31G(d,p).

[0202] When Host D, Sensitizer B, and the heterocyclic compound satisfy Condition D-1 and/or D-2, FRET from Sensitizer B to the heterocyclic compound may be facilitated, and accordingly, the organic light-emitting device may have improved luminescence efficiency.

[0203] In the Third Embodiment and the Fourth Embodiment, an amount of the sensitizer in the emission layer may be in a range of about 5 wt % to about 50 wt %, for example, about 10 wt % to about 30 wt %. Within these ranges, the energy transfer in the emission layer may be effectively achieved, and accordingly, an organic light-emitting device having high efficiency and a long lifespan may be obtained.

[0204] In the Third Embodiment and the Fourth Embodiment, an amount of the heterocyclic compound in the emission layer may be in a range of about 0.01 wt % to about 15 wt %, for example, about 0.05 wt % to about 3 wt %, but embodiments are not limited thereto.

[0205] In the Third Embodiment and the Fourth Embodiment, the sensitizer and the heterocyclic compound may further satisfy Condition 5:

0 μs<T.sub.decay(HC)<5 μs  Condition 5

[0206] wherein, in Condition 5,

[0207] T.sub.decay(HC) indicates a decay time of the heterocyclic compound.

[0208] The decay time of the heterocyclic compound was measured from a time-resolved photoluminescence (TRPL) spectrum at room temperature of a film (hereinafter, referred to as “Film HC”) having a thickness of 40 nm formed by vacuum-depositing the host and the heterocyclic compound included in the emission layer on a quartz substrate at a weight ratio of 90:10 at a vacuum pressure of 10.sup.−7 torr.

Fifth Embodiment—Descriptions of FIG. 4E

[0209] In the Fifth Embodiment, the heterocyclic compound may be used as a delayed fluorescence emitter, and the emission layer may include a sensitizer, for example, a delayed fluorescence sensitizer. In the Fifth Embodiment, the emission layer may further include a host (hereinafter, referred to as ‘Host E’ which is not identical to the heterocyclic compound and the sensitizer) and a sensitizer (hereinafter, referred to as ‘Sensitizer C’ which is not identical to Host E and the heterocyclic compound). Host E and Sensitizer C may respectively be understood by referring to a host material and a sensitizer material described below, but embodiments are not limited thereto.

[0210] According to the Fifth Embodiment, emission components emitted from the heterocyclic compound may account for about 80% or more, for example, about 90% or more (and for example, about 95% or more), of the total emission components emitted from the emission layer. For example, the heterocyclic compound may emit fluorescence and/or delayed fluorescence. In addition, Host E and Sensitizer C may not each emit light.

[0211] Here, the heterocyclic compound may emit fluorescence and/or delayed fluorescence, and the emission components of the heterocyclic compound may be a total of prompt emission components of the heterocyclic compound and delayed fluorescence components by RISC of the heterocyclic compound.

[0212] FIG. 4E depicts the general energy transfer of the Fifth Embodiment.

[0213] Singlet excitons generated at a ratio of 25% in Host E included in the emission layer may be transferred to a singlet state of Sensitizer C through FRET, and energy of triplet excitons generated at a ratio of 75% in Host E may be transferred to a triplet state of Sensitizer C, wherein the energy transferred to the singlet state of Sensitizer B may undergo ISC to the triplet state, and then, the triplet energy of Sensitizer B may be transferred to the heterocyclic compound through FRET. The energy transferred to the triplet state of Sensitizer C may undergo RISC to the singlet state. In addition, in the case of Sensitizer C, the energy of the triplet excitons generated in Sensitizer C may undergo reverse transfer to Host E first, and then to the heterocyclic compound, thereby emitting light by reverse intersystem transfer.

[0214] Accordingly, by transferring all the singlet excitons and triplet excitons generated in the emission layer to a dopant, an organic light-emitting device having improved efficiency may be obtained. In addition, since an organic light-emitting device thus obtained has significantly reduced energy loss, lifespan characteristics thereof may be also improved.

[0215] In the Fifth Embodiment, when the emission layer further includes, in addition to the heterocyclic compound, Host E and Sensitizer C, Host E and Sensitizer C may satisfy Condition E-1, E-2, and/or E-3:

S.sub.1(H.sub.E)≥S.sub.1(S.sub.C)  Condition E-1

S.sub.1(S.sub.C)≥S.sub.1(HC)  Condition E-2

T.sub.1(S.sub.C)≥T.sub.1(HC)  Condition E-3

[0216] wherein, in Conditions E-1, E-2, and E-3,

[0217] S.sub.1(H.sub.E) indicates a lowest excited singlet energy level of Host E,

[0218] S.sub.1(S.sub.C) indicates a lowest excited singlet energy level of Sensitizer C,

[0219] S.sub.1(HC) indicates a lowest excited singlet energy level of the heterocyclic compound,

[0220] T.sub.1(S.sub.C) indicates a lowest excited triplet energy level of Sensitizer C, and

[0221] T.sub.1(HC) indicates a lowest excited triplet energy level of the heterocyclic compound.

[0222] S.sub.1(H.sub.E), S.sub.1(S.sub.C), S.sub.1(HC), T.sub.1(S.sub.C), and T.sub.1(HC) may be evaluated using the DFT method of the Gaussian program with structure optimization performed at a degree of B3LYP/6-31 G(d,p).

[0223] When Host E, Sensitizer C, and the heterocyclic compound satisfy Condition E-1, E-2, and/or E-3, Dexter transfer and FRET from Sensitizer C to the heterocyclic compound may be facilitated, and accordingly, the organic light-emitting device may have improved luminescence efficiency.

[0224] In the Fifth Embodiment, an amount of Sensitizer C in the emission layer may be in a range of about 5 wt % to about 50 wt %, for example, about 10 wt % to about 30 wt %. Within these ranges, the energy transfer in the emission layer may be effectively achieved, and accordingly, an organic light-emitting device having high efficiency and a long lifespan may be obtained.

[0225] In the Fifth Embodiment, an amount of the heterocyclic compound in the emission layer may be in a range of about 0.01 wt % to about 15 wt %, for example, about 0.05 wt % to about 3 wt %, but embodiments are not limited thereto.

[Host in Emission Layer 15]

[0226] The host may include no metal atom.

[0227] In an embodiment, the host may include one kind of host. When the host includes one kind of host, the one host may be a bipolar host, an electron-transporting host, or a hole-transporting host, which will be described below.

[0228] In one or more embodiments, the host may include a mixture of two or more different types of host. For example, the host may be a mixture of an electron-transporting host and a hole-transporting host, a mixture of two types of electron-transporting hosts different from each other, or a mixture of two types of hole-transporting hosts different from each other. The electron-transporting host and the hole-transporting host may be understood by referring to the related descriptions provided below.

[0229] In one or more embodiments, the host may include an electron-transporting host including at least one electron-transporting moiety and a hole-transporting host that is free of an electron-transporting moiety.

[0230] In an embodiment, the electron-transporting moiety used herein may be a cyano group, a π electron-depleted nitrogen-containing cyclic group, and a group represented by one of the following formulae:

##STR00137##

[0231] In the formulae, *, *′, and *″ each indicate a binding site to a neighboring atom.

[0232] In one or more embodiments, the electron-transporting host included in the emission layer 15 may include at least one of a cyano group and a π electron-depleted nitrogen-containing cyclic group.

[0233] In one or more embodiments, the electron-transporting host included in the emission layer 15 may include at least one cyano group.

[0234] In one or more embodiments, the electron-transporting host included in the emission layer 15 may include at least one cyano group and at least one π electron depleted nitrogen-containing cyclic group.

[0235] In one or more embodiments, the host may include an electron-transporting host and a hole-transporting host, wherein the electron-transporting host may include at least one π electron-depleted nitrogen-free cyclic group and at least one electron-transporting moiety, and the hole-transporting host may include at least one π electron-depleted nitrogen-free cyclic group and may not include an electron-transporting moiety.

[0236] The term “π electron-depleted nitrogen-containing cyclic group” as used herein refers to a cyclic group having at least one *—N═*′ moiety, and for example, may be: an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, or an azacarbazole group; and a condensed cyclic group in which two or more π electron-efficient nitrogen-containing cyclic groups are condensed with each other.

[0237] Meanwhile, the π electron-depleted nitrogen-free cyclic group may be: a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentacene group, a rubicene group, a corogen group, an ovalene group, a pyrrole group, an isoindole group, an indole group, a furan group, a thiophene group, a benzofuran group, a benzothiophene group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a triindolobenzene group, or a condensed cyclic group of two or more π electron-depleted nitrogen-free cyclic groups, but embodiments of the present disclosure are not limited thereto.

[0238] In one or more embodiments, the electron-transporting host may be compounds represented by Formula E-1, and

[0239] the hole-transporting host may be a compound represented by Formula H-1, but embodiments of the present disclosure are not limited thereto:

[Ar.sub.301].sub.xb11-[(L.sub.301).sub.xb1-R.sub.301].sub.xb21  <Formula E-1>

[0240] wherein, in Formula E-1,

[0241] Ar.sub.301 may be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

[0242] xb11 may be 1, 2, or 3,

[0243] L.sub.301 may be a single bond, a group represented by one of the following formulae, a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group, or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group, wherein *, *′, and *″ in the following formulae each indicate a binding site to a neighboring atom,

##STR00138##

[0244] xb1 may be an integer from 1 to 5,

[0245] R.sub.301 may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent aromatic condensed polycyclic group, a substituted or unsubstituted monovalent aromatic condensed heteropolycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.301)(Q.sub.302)(Q.sub.303), —N(Q.sub.301)(Q.sub.302), —B(Q.sub.301)(Q.sub.302), —C(═O)(Q.sub.301), —S(═O).sub.2(Q.sub.301), —S(═O)(Q.sub.301), —P(═O)(Q.sub.301)(Q.sub.302), or —P(═S)(Q.sub.301)(Q.sub.302),

[0246] xb21 may be an integer from 1 to 5,

[0247] Q.sub.301 to Q.sub.303 may each independently be a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, and

[0248] at least one of Conditions H-1 to H-3 may be satisfied:

[0249] Condition H-1:

[0250] at least one of Ar.sub.301, L.sub.301, and R.sub.301 in Formula E-1 each independently includes a π electron-depleted nitrogen-containing cyclic group,

[0251] Condition H-2:

[0252] L.sub.301 in Formula E-1 is a group represented by one of the following formulae:

##STR00139##

and

[0253] Condition H-3:

[0254] R.sub.301 in Formula E-1 is a cyano group, —S(═O).sub.2(Q.sub.301), —S(═O)(Q.sub.301), —P(═O)(Q.sub.301)(Q.sub.302), and —P(═S)(Q.sub.301)(Q.sub.302),

##STR00140##

[0255] wherein, in Formulae H-1, 11, and 12,

[0256] L.sub.401 may be:

[0257] a single bond; or

[0258] a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentacene group, a rubicene group, a corogen group, an ovalene group, a pyrrole group, an isoindole group, an indole group, a furan group, a thiophene group, a benzofuran group, a benzothiophene group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, or a triindolobenzene group, each unsubstituted or substituted with at least one deuterium, a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triphenylenyl group, a biphenyl group, a terphenyl group, a tetraphenyl group, —Si(Q.sub.401)(Q.sub.402)(Q.sub.403), or any combination thereof,

[0259] xd1 may be an integer from 1 to 10, wherein, when xd1 is 2 or more, two or more of L.sub.401 may be identical to or different from each other,

[0260] Ar.sub.401 may be a group represented by Formulae 11 and 12,

[0261] Ar.sub.402 may be:

[0262] a group represented by Formulae 11 or 12, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, or a triphenylenyl group; or

[0263] a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, or a triphenylenyl group, each substituted with at least one deuterium, a hydroxyl group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, a triphenylenyl group, or any combination thereof,

[0264] CY.sub.401 and CY.sub.402 may each independently be a benzene group, a naphthalene group, a fluorene group, a carbazole group, a benzocarbazole group, an indolocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzosilole group, a benzonaphthofuran group, a benzonaphthothiophene group, or a benzonaphthosilole group,

[0265] A.sub.21 may be a single bond, O, S, N(R.sub.51), C(R.sub.51)(R.sub.52), or Si(R.sub.51)(R.sub.52),

[0266] A.sub.22 may be a single bond, O, S, N(R.sub.53), C(R.sub.53)(R.sub.54), or Si(R.sub.53)(R.sub.54),

[0267] at least one of A.sub.21 and A.sub.22 in Formula 12 may not be a single bond,

[0268] R.sub.51 to R.sub.54, R.sub.60, and R.sub.70 may each independently be:

[0269] hydrogen, deuterium, a hydroxyl group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group;

[0270] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with at least one deuterium, a hydroxyl group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, or any combination thereof;

[0271] a π electron-depleted nitrogen-free cyclic group (for example, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, and a triphenylenyl group);

[0272] a π electron-depleted nitrogen-free cyclic group (for example, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, and a triphenylenyl group), each substituted with at least one deuterium, a hydroxyl group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group or any combination thereof; or

[0273] —Si(Q.sub.404)(Q.sub.405)(Q.sub.406),

[0274] e1 and e2 may each independently be an integer from 0 to 10,

[0275] Q.sub.401 to Q.sub.406 may each independently be hydrogen, deuterium, a hydroxyl group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, a terphenyl group, or a triphenylenyl group, and

[0276] * indicates a binding site to a neighboring atom.

[0277] In an embodiment, Ar.sub.301 and L.sub.301 in Formula E-1 may each independently be a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, or an azacarbazole group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, a cyano-containing naphthyl group, a pyridinyl group, a phenylpyridinyl group, a diphenylpyridinyl group, a biphenylpyridinyl group, a di(biphenyl)pyridinyl group, a pyrazinyl group, a phenylpyrazinyl group, a diphenylpyrazinyl group, a biphenylpyrazinyl group, a di(biphenyl)pyrazinyl group, a pyridazinyl group, a phenylpyridazinyl group, a diphenylpyridazinyl group, a biphenylpyridazinyl group, a di(biphenyl)pyridazinyl group, a pyrimidinyl group, a phenylpyrimidinyl group, a diphenylpyrimidinyl group, a biphenylpyrimidinyl group, a di(biphenyl)pyrimidinyl group, a triazinyl group, a phenyltriazinyl group, a diphenyltriazinyl group, a biphenyltriazinyl group, a di(biphenyl)triazinyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof,

[0278] at least one of L.sub.301(s) in the number of xb1 may each independently be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, or an azacarbazole group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, a cyano-containing naphthyl group, a pyridinyl group, a phenylpyridinyl group, a diphenylpyridinyl group, a biphenylpyridinyl group, a di(biphenyl)pyridinyl group, a pyrazinyl group, a phenylpyrazinyl group, a diphenylpyrazinyl group, a biphenylpyrazinyl group, a di(biphenyl)pyrazinyl group, a pyridazinyl group, a phenylpyridazinyl group, a diphenylpyridazinyl group, a biphenylpyridazinyl group, a di(biphenyl)pyridazinyl group, a pyrimidinyl group, a phenylpyrimidinyl group, a diphenylpyrimidinyl group, a biphenylpyrimidinyl group, a di(biphenyl)pyrimidinyl group, a triazinyl group, a phenyltriazinyl group, a diphenyltriazinyl group, a biphenyltriazinyl group, a di(biphenyl)triazinyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof, and

[0279] R.sub.301 may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a tetraphenyl group, a naphthyl group, a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, a cyano-containing tetraphenyl group, a cyano-containing naphthyl group, a pyridinyl group, a phenylpyridinyl group, a diphenylpyridinyl group, a biphenylpyridinyl group, a di(biphenyl)pyridinyl group, a pyrazinyl group, a phenylpyrazinyl group, a diphenylpyrazinyl group, a biphenylpyrazinyl group, a di(biphenyl)pyrazinyl group, a pyridazinyl group, a phenylpyridazinyl group, a diphenylpyridazinyl group, a biphenylpyridazinyl group, a di(biphenyl)pyridazinyl group, a pyrimidinyl group, a phenylpyrimidinyl group, a diphenylpyrimidinyl group, a biphenylpyrimidinyl group, a di(biphenyl)pyrimidinyl group, a triazinyl group, a phenyltriazinyl group, a diphenyltriazinyl group, a biphenyltriazinyl group, a di(biphenyl)triazinyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), or —P(═O)(Q.sub.31)(Q.sub.32), and

[0280] Q.sub.31 to Q.sub.33 may each independently be a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, but embodiments of the present disclosure are not limited thereto.

[0281] In one or more embodiments, Ar.sub.301 may be:

[0282] a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, or a dibenzothiophene group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, a cyano-containing naphthyl group, a pyridinyl group, a phenylpyridinyl group, a diphenylpyridinyl group, a biphenylpyridinyl group, a di(biphenyl)pyridinyl group, a pyrazinyl group, a phenylpyrazinyl group, a diphenylpyrazinyl group, a biphenylpyrazinyl group, a di(biphenyl)pyrazinyl group, a pyridazinyl group, a phenylpyridazinyl group, a diphenylpyridazinyl group, a biphenylpyridazinyl group, a di(biphenyl)pyridazinyl group, a pyrimidinyl group, a phenylpyrimidinyl group, a diphenylpyrimidinyl group, a biphenylpyrimidinyl group, a di(biphenyl)pyrimidinyl group, a triazinyl group, a phenyltriazinyl group, a diphenyltriazinyl group, a biphenyltriazinyl group, a di(biphenyl)triazinyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof; or

[0283] a group represented by one of Formulae 5-1 to 5-3 or Formulae 6-1 to 6-33, and

[0284] L.sub.301 may be a group represented by one of Formulae 5-1 to 5-3 and Formulae 6-1 to 6-33:

##STR00141## ##STR00142## ##STR00143## ##STR00144##

[0285] In Formulae 5-1 to 5-3 and 6-1 to 6-33,

[0286] Z.sub.1 may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, a cyano-containing naphthyl group, a pyridinyl group, a phenylpyridinyl group, a diphenylpyridinyl group, a biphenylpyridinyl group, a di(biphenyl)pyridinyl group, a pyrazinyl group, a phenylpyrazinyl group, a diphenylpyrazinyl group, a biphenylpyrazinyl group, a di(biphenyl)pyrazinyl group, a pyridazinyl group, a phenylpyridazinyl group, a diphenylpyridazinyl group, a biphenylpyridazinyl group, a di(biphenyl)pyridazinyl group, a pyrimidinyl group, a phenylpyrimidinyl group, a diphenylpyrimidinyl group, a biphenylpyrimidinyl group, a di(biphenyl)pyrimidinyl group, a triazinyl group, a phenyltriazinyl group, a diphenyltriazinyl group, a biphenyltriazinyl group, a di(biphenyl)triazinyl group, -Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), or —P(═O)(Q.sub.31)(Q.sub.32),

[0287] d4 may be 0, 1, 2, 3, or 4,

[0288] d3 may be 0, 1, 2, or 3,

[0289] d2 may be 0, 1, or 2,

[0290] * and *′ each indicate a binding site to a neighboring atom, and

[0291] Q.sub.31 to Q.sub.33 may respectively be the same as described herein.

[0292] In one or more embodiments, L.sub.301 may be a group represented by Formulae 5-2, 5-3, and 6-8 to 6-33.

[0293] In one or more embodiments, R.sub.301 may be a cyano group or a group represented by one of Formula 7-1 to 7-18, and at least one of Ar.sub.402(s) in the number of xd11 may be a group represented by one of Formulae 7-1 to 7-18, but embodiments of the present disclosure are not limited thereto:

##STR00145## ##STR00146## ##STR00147##

[0294] In Formulae 7-1 to 7-18,

[0295] xb41 to xb44 may each be 0, 1, or 2, wherein xb41 in Formula 7-10 is not 0, the sum of xb41 and xb42 in Formulae 7-11 to 7-13 is not 0, the sum of xb41, xb42, and xb43 in Formulae 7-14 to 7-16 is not 0, the sum of xb41, xb42, xb43, and xb44 in Formulae 7-17 and 7-18 is not 0, and * indicates a binding site to a neighboring atom.

[0296] In Formula E-1, two or more of Ar.sub.301 may be identical to or different from each other, and two or more of L.sub.301 may be identical to or different from each other. In Formula H-1, two or more of L.sub.401 may be identical to or different from each other, and two or more of Ar.sub.402 may be identical to or different from each other.

[0297] In an embodiment, the electron-transporting host includes i) at least one of a cyano group, a pyrimidine group, a pyrazine group, a triazine group, or a combination thereof, or ii) a triphenylene group, and the hole-transporting host may include a carbazole group.

[0298] In one or more embodiments, the electron-transporting host may include at least one cyano group.

[0299] The electron-transporting host may be, for example, compounds of Groups HE1 to HE7, but embodiments of the present disclosure are not limited thereto:

##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163## ##STR00164## ##STR00165## ##STR00166## ##STR00167## ##STR00168## ##STR00169## ##STR00170## ##STR00171## ##STR00172## ##STR00173## ##STR00174## ##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181## ##STR00182## ##STR00183## ##STR00184## ##STR00185## ##STR00186##

##STR00187## ##STR00188## ##STR00189## ##STR00190## ##STR00191## ##STR00192## ##STR00193## ##STR00194## ##STR00195## ##STR00196## ##STR00197## ##STR00198## ##STR00199## ##STR00200## ##STR00201## ##STR00202## ##STR00203## ##STR00204## ##STR00205## ##STR00206## ##STR00207## ##STR00208## ##STR00209## ##STR00210##

##STR00211## ##STR00212## ##STR00213## ##STR00214## ##STR00215## ##STR00216## ##STR00217## ##STR00218## ##STR00219## ##STR00220## ##STR00221## ##STR00222## ##STR00223## ##STR00224## ##STR00225## ##STR00226## ##STR00227## ##STR00228## ##STR00229## ##STR00230## ##STR00231## ##STR00232## ##STR00233## ##STR00234## ##STR00235## ##STR00236## ##STR00237## ##STR00238## ##STR00239## ##STR00240## ##STR00241## ##STR00242## ##STR00243## ##STR00244## ##STR00245## ##STR00246##

##STR00247## ##STR00248## ##STR00249## ##STR00250## ##STR00251## ##STR00252## ##STR00253## ##STR00254## ##STR00255## ##STR00256## ##STR00257## ##STR00258## ##STR00259## ##STR00260## ##STR00261## ##STR00262## ##STR00263## ##STR00264## ##STR00265## ##STR00266## ##STR00267## ##STR00268## ##STR00269## ##STR00270## ##STR00271## ##STR00272## ##STR00273## ##STR00274## ##STR00275## ##STR00276## ##STR00277## ##STR00278## ##STR00279## ##STR00280## ##STR00281## ##STR00282## ##STR00283## ##STR00284## ##STR00285## ##STR00286## ##STR00287## ##STR00288##

##STR00289## ##STR00290## ##STR00291## ##STR00292## ##STR00293## ##STR00294## ##STR00295## ##STR00296## ##STR00297## ##STR00298## ##STR00299## ##STR00300## ##STR00301## ##STR00302## ##STR00303## ##STR00304## ##STR00305## ##STR00306## ##STR00307## ##STR00308## ##STR00309## ##STR00310## ##STR00311## ##STR00312## ##STR00313## ##STR00314## ##STR00315## ##STR00316## ##STR00317## ##STR00318## ##STR00319## ##STR00320## ##STR00321## ##STR00322## ##STR00323## ##STR00324## ##STR00325## ##STR00326## ##STR00327## ##STR00328## ##STR00329## ##STR00330## ##STR00331## ##STR00332## ##STR00333## ##STR00334## ##STR00335## ##STR00336## ##STR00337## ##STR00338## ##STR00339## ##STR00340## ##STR00341## ##STR00342## ##STR00343## ##STR00344## ##STR00345## ##STR00346## ##STR00347## ##STR00348## ##STR00349## ##STR00350## ##STR00351##

##STR00352## ##STR00353## ##STR00354## ##STR00355## ##STR00356## ##STR00357## ##STR00358## ##STR00359## ##STR00360## ##STR00361## ##STR00362## ##STR00363## ##STR00364## ##STR00365## ##STR00366## ##STR00367## ##STR00368## ##STR00369## ##STR00370## ##STR00371## ##STR00372## ##STR00373## ##STR00374## ##STR00375## ##STR00376## ##STR00377## ##STR00378## ##STR00379## ##STR00380## ##STR00381## ##STR00382## ##STR00383## ##STR00384## ##STR00385## ##STR00386## ##STR00387## ##STR00388## ##STR00389## ##STR00390## ##STR00391## ##STR00392## ##STR00393## ##STR00394## ##STR00395## ##STR00396## ##STR00397## ##STR00398## ##STR00399## ##STR00400## ##STR00401## ##STR00402## ##STR00403## ##STR00404## ##STR00405## ##STR00406## ##STR00407##

##STR00408## ##STR00409## ##STR00410## ##STR00411## ##STR00412## ##STR00413## ##STR00414## ##STR00415## ##STR00416## ##STR00417## ##STR00418## ##STR00419## ##STR00420## ##STR00421## ##STR00422## ##STR00423## ##STR00424## ##STR00425## ##STR00426## ##STR00427## ##STR00428## ##STR00429## ##STR00430## ##STR00431## ##STR00432## ##STR00433## ##STR00434## ##STR00435## ##STR00436##

##STR00437## ##STR00438## ##STR00439## ##STR00440## ##STR00441## ##STR00442## ##STR00443## ##STR00444## ##STR00445## ##STR00446## ##STR00447## ##STR00448## ##STR00449## ##STR00450## ##STR00451## ##STR00452## ##STR00453## ##STR00454## ##STR00455## ##STR00456## ##STR00457## ##STR00458## ##STR00459## ##STR00460## ##STR00461## ##STR00462## ##STR00463## ##STR00464##

##STR00465## ##STR00466## ##STR00467## ##STR00468## ##STR00469## ##STR00470## ##STR00471## ##STR00472## ##STR00473## ##STR00474## ##STR00475## ##STR00476## ##STR00477## ##STR00478## ##STR00479## ##STR00480## ##STR00481## ##STR00482## ##STR00483## ##STR00484## ##STR00485## ##STR00486## ##STR00487## ##STR00488## ##STR00489## ##STR00490## ##STR00491## ##STR00492## ##STR00493## ##STR00494## ##STR00495## ##STR00496## ##STR00497## ##STR00498## ##STR00499## ##STR00500## ##STR00501## ##STR00502## ##STR00503## ##STR00504## ##STR00505## ##STR00506## ##STR00507## ##STR00508## ##STR00509## ##STR00510## ##STR00511## ##STR00512## ##STR00513## ##STR00514## ##STR00515## ##STR00516## ##STR00517## ##STR00518## ##STR00519##

##STR00520## ##STR00521## ##STR00522## ##STR00523## ##STR00524## ##STR00525## ##STR00526## ##STR00527## ##STR00528## ##STR00529## ##STR00530## ##STR00531##

##STR00532## ##STR00533## ##STR00534## ##STR00535## ##STR00536## ##STR00537## ##STR00538## ##STR00539## ##STR00540## ##STR00541## ##STR00542## ##STR00543## ##STR00544## ##STR00545## ##STR00546## ##STR00547## ##STR00548## ##STR00549## ##STR00550## ##STR00551## ##STR00552## ##STR00553## ##STR00554## ##STR00555## ##STR00556## ##STR00557## ##STR00558## ##STR00559## ##STR00560## ##STR00561## ##STR00562## ##STR00563## ##STR00564## ##STR00565## ##STR00566## ##STR00567## ##STR00568## ##STR00569## ##STR00570## ##STR00571## ##STR00572## ##STR00573## ##STR00574## ##STR00575## ##STR00576## ##STR00577## ##STR00578## ##STR00579## ##STR00580## ##STR00581## ##STR00582## ##STR00583## ##STR00584## ##STR00585## ##STR00586## ##STR00587## ##STR00588## ##STR00589## ##STR00590## ##STR00591## ##STR00592## ##STR00593## ##STR00594## ##STR00595##

##STR00596## ##STR00597## ##STR00598## ##STR00599## ##STR00600## ##STR00601## ##STR00602## ##STR00603## ##STR00604## ##STR00605## ##STR00606## ##STR00607## ##STR00608## ##STR00609## ##STR00610## ##STR00611## ##STR00612## ##STR00613## ##STR00614## ##STR00615## ##STR00616## ##STR00617## ##STR00618## ##STR00619## ##STR00620## ##STR00621## ##STR00622## ##STR00623## ##STR00624## ##STR00625## ##STR00626## ##STR00627## ##STR00628## ##STR00629## ##STR00630## ##STR00631## ##STR00632## ##STR00633## ##STR00634## ##STR00635## ##STR00636## ##STR00637## ##STR00638## ##STR00639## ##STR00640## ##STR00641## ##STR00642## ##STR00643## ##STR00644## ##STR00645## ##STR00646##

##STR00647## ##STR00648## ##STR00649## ##STR00650## ##STR00651## ##STR00652## ##STR00653## ##STR00654## ##STR00655## ##STR00656## ##STR00657## ##STR00658## ##STR00659## ##STR00660## ##STR00661## ##STR00662## ##STR00663## ##STR00664## ##STR00665##

##STR00666## ##STR00667## ##STR00668## ##STR00669## ##STR00670## ##STR00671## ##STR00672## ##STR00673## ##STR00674## ##STR00675## ##STR00676## ##STR00677## ##STR00678## ##STR00679## ##STR00680## ##STR00681## ##STR00682## ##STR00683## ##STR00684## ##STR00685## ##STR00686## ##STR00687## ##STR00688## ##STR00689## ##STR00690## ##STR00691## ##STR00692## ##STR00693## ##STR00694## ##STR00695## ##STR00696## ##STR00697## ##STR00698## ##STR00699## ##STR00700## ##STR00701## ##STR00702## ##STR00703## ##STR00704## ##STR00705## ##STR00706## ##STR00707## ##STR00708## ##STR00709## ##STR00710##

##STR00711## ##STR00712## ##STR00713## ##STR00714## ##STR00715## ##STR00716## ##STR00717## ##STR00718## ##STR00719## ##STR00720## ##STR00721## ##STR00722## ##STR00723## ##STR00724## ##STR00725## ##STR00726## ##STR00727## ##STR00728## ##STR00729##

[0300] In one or more embodiments, the electron-transporting host may include DPEPO or TSPO1:

##STR00730##

[0301] In one or more embodiments, the hole-transporting host may be compounds of Group HH1, but embodiments of the present disclosure are not limited thereto:

##STR00731## ##STR00732## ##STR00733## ##STR00734## ##STR00735## ##STR00736## ##STR00737## ##STR00738## ##STR00739## ##STR00740## ##STR00741## ##STR00742## ##STR00743## ##STR00744## ##STR00745## ##STR00746##

[0302] In one or more embodiments, the bipolar host may be compounds of Group HEH1, but embodiments of the present disclosure are not limited thereto:

##STR00747## ##STR00748## ##STR00749## ##STR00750## ##STR00751## ##STR00752## ##STR00753## ##STR00754## ##STR00755## ##STR00756## ##STR00757## ##STR00758## ##STR00759## ##STR00760## ##STR00761## ##STR00762## ##STR00763## ##STR00764## ##STR00765## ##STR00766## ##STR00767## ##STR00768## ##STR00769## ##STR00770## ##STR00771## ##STR00772## ##STR00773## ##STR00774## ##STR00775## ##STR00776## ##STR00777## ##STR00778## ##STR00779## ##STR00780## ##STR00781## ##STR00782## ##STR00783## ##STR00784## ##STR00785## ##STR00786## ##STR00787## ##STR00788## ##STR00789## ##STR00790## ##STR00791## ##STR00792## ##STR00793## ##STR00794## ##STR00795## ##STR00796## ##STR00797## ##STR00798## ##STR00799##

##STR00800## ##STR00801## ##STR00802## ##STR00803## ##STR00804## ##STR00805## ##STR00806## ##STR00807## ##STR00808## ##STR00809## ##STR00810## ##STR00811## ##STR00812## ##STR00813## ##STR00814## ##STR00815## ##STR00816## ##STR00817## ##STR00818## ##STR00819## ##STR00820## ##STR00821## ##STR00822## ##STR00823## ##STR00824## ##STR00825## ##STR00826## ##STR00827## ##STR00828## ##STR00829## ##STR00830## ##STR00831## ##STR00832## ##STR00833## ##STR00834## ##STR00835## ##STR00836## ##STR00837## ##STR00838## ##STR00839##

[0303] In Compounds 1 to 432,

[0304] Ph represents a phenyl group.

[0305] In one or more embodiments, the hole-transporting host may include o-CBP or mCP:

##STR00840##

[0306] In an embodiment, the host may be a fluorescent host, and such a fluorescent host may be, for example, represented by one of Formulae FH-1 to FH-4.

[0307] In an embodiment, the fluorescent host may be represented by Formula FH-1:

##STR00841##

[0308] In Formula FH-1,

[0309] Ar.sub.1 to Ar.sub.3 may each independently be a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), or —P(═O)(Q.sub.8)(Q),

[0310] Ar.sub.1 to Ar.sub.3 may each independently be a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group,

[0311] L.sub.10 may be an unsubstituted or substituted C.sub.5-C.sub.30 carbocyclic group or an unsubstituted or substituted C.sub.1-C.sub.30 heterocyclic group,

[0312] a10 may be an integer from 0 to 3, wherein, when a10 is 2 or more, two or more of L.sub.10 may be identical to or different from each other,

[0313] R.sub.10 and R.sub.20 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), or —P(═O)(Q.sub.8)(Q),

[0314] b10 and b20 may each independently be an integer from 1 to 8,

[0315] when b10 is 2 or more, two or more of R.sub.10 may be identical to or different from each other, and when b20 is 2 or more, two or more of R.sub.20 may be identical to or different from each other,

[0316] c10 may be an integer from 1 to 9, and

[0317] when c10 is 2 or more two or more of -[(L.sub.10).sub.a10-(R.sub.10).sub.b10] may be identical to or different from each other.

[0318] In detail, the fluorescent host represented by Formula FH-1 may be compounds of Group FH1, embodiments of the present disclosure are not limited thereto:

##STR00842## ##STR00843## ##STR00844## ##STR00845## ##STR00846## ##STR00847## ##STR00848## ##STR00849## ##STR00850## ##STR00851## ##STR00852## ##STR00853## ##STR00854## ##STR00855## ##STR00856## ##STR00857## ##STR00858## ##STR00859## ##STR00860## ##STR00861##

[0319] In one or more embodiments, the fluorescent host may be represented by Formula FH-2:

##STR00862##

[0320] In Formula FH-2,

[0321] X.sub.1 may be O or S,

[0322] A.sub.1 may be a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group,

[0323] L.sub.11 may be an unsubstituted or substituted C.sub.5-C.sub.60 carbocyclic group or an unsubstituted or substituted C.sub.1-C.sub.60 heterocyclic group,

[0324] a11 may be an integer from 0 to 3,

[0325] Ar.sub.11 and Ar.sub.12 may each independently be a C.sub.6-C.sub.60 aryl group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group, each unsubstituted or substituted with at least one R.sub.a,

[0326] b11 may be an integer from 1 to 5,

[0327] R.sub.11, R.sub.12, and R.sub.a may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.4)(Q.sub.5), or —B(Q.sub.6)(Q.sub.7),

[0328] c11 may be an integer from 1 to 20,

[0329] c12 may be an integer from 1 to 4,

[0330] when c11 is 2 or more, two neighboring R.sub.11(s) may optionally be linked to each other to form a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group,

[0331] when c12 is 2 or more, two neighboring R.sub.12(s) may optionally be linked to each other to form a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group,

[0332] A.sub.1 and Ar.sub.12 may optionally be linked to each other via a first linking group a single bond, *—Ar.sub.31—*′, *—O—*′, *—S—*′, *—[C(R.sub.31)(R.sub.32)].sub.k11—*′, *—C(R.sub.31)═*′, *═C(R.sub.31)—*′, *—C(R.sub.31)═C(R.sub.32)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C≡C—*′, *—N(R.sub.31)—*′, *—P(R.sub.31)—*′, *—[Si(R.sub.31)(R.sub.32)].sub.k11—*, or *—P(R.sub.31)(R.sub.32)—*′ to form a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group,

[0333] Ar.sub.31 may be a C.sub.5-C.sub.30 carbocyclic group,

[0334] R.sub.31 and R.sub.32 may each be the same as described in connection with R.sub.11, and

[0335] k11 may be 1, 2, 3, or 4.

[0336] In detail, the fluorescent host represented by Formula FH-2 may be a compound of Group FH2, embodiments of the present disclosure are not limited thereto:

##STR00863## ##STR00864## ##STR00865## ##STR00866## ##STR00867## ##STR00868## ##STR00869## ##STR00870## ##STR00871## ##STR00872## ##STR00873## ##STR00874## ##STR00875## ##STR00876## ##STR00877## ##STR00878## ##STR00879## ##STR00880## ##STR00881## ##STR00882## ##STR00883## ##STR00884## ##STR00885## ##STR00886## ##STR00887## ##STR00888## ##STR00889## ##STR00890## ##STR00891## ##STR00892## ##STR00893## ##STR00894## ##STR00895## ##STR00896## ##STR00897## ##STR00898## ##STR00899## ##STR00900## ##STR00901## ##STR00902## ##STR00903## ##STR00904## ##STR00905##

##STR00906## ##STR00907## ##STR00908## ##STR00909## ##STR00910## ##STR00911## ##STR00912## ##STR00913## ##STR00914## ##STR00915## ##STR00916## ##STR00917## ##STR00918## ##STR00919## ##STR00920## ##STR00921## ##STR00922## ##STR00923## ##STR00924## ##STR00925## ##STR00926## ##STR00927## ##STR00928## ##STR00929## ##STR00930## ##STR00931## ##STR00932## ##STR00933## ##STR00934## ##STR00935## ##STR00936## ##STR00937## ##STR00938## ##STR00939## ##STR00940## ##STR00941## ##STR00942## ##STR00943## ##STR00944## ##STR00945## ##STR00946## ##STR00947## ##STR00948## ##STR00949## ##STR00950## ##STR00951## ##STR00952## ##STR00953## ##STR00954## ##STR00955## ##STR00956## ##STR00957## ##STR00958## ##STR00959## ##STR00960## ##STR00961## ##STR00962## ##STR00963## ##STR00964## ##STR00965## ##STR00966## ##STR00967## ##STR00968## ##STR00969## ##STR00970## ##STR00971## ##STR00972## ##STR00973## ##STR00974## ##STR00975## ##STR00976## ##STR00977## ##STR00978## ##STR00979## ##STR00980## ##STR00981## ##STR00982## ##STR00983## ##STR00984## ##STR00985## ##STR00986## ##STR00987## ##STR00988## ##STR00989## ##STR00990## ##STR00991##

##STR00992## ##STR00993## ##STR00994## ##STR00995## ##STR00996## ##STR00997## ##STR00998## ##STR00999## ##STR01000## ##STR01001## ##STR01002## ##STR01003## ##STR01004## ##STR01005## ##STR01006## ##STR01007## ##STR01008## ##STR01009## ##STR01010## ##STR01011## ##STR01012## ##STR01013## ##STR01014## ##STR01015## ##STR01016## ##STR01017## ##STR01018## ##STR01019## ##STR01020## ##STR01021## ##STR01022## ##STR01023## ##STR01024## ##STR01025## ##STR01026## ##STR01027## ##STR01028## ##STR01029## ##STR01030## ##STR01031## ##STR01032## ##STR01033## ##STR01034## ##STR01035## ##STR01036## ##STR01037## ##STR01038## ##STR01039## ##STR01040## ##STR01041##

##STR01042## ##STR01043## ##STR01044## ##STR01045## ##STR01046## ##STR01047## ##STR01048## ##STR01049## ##STR01050## ##STR01051## ##STR01052## ##STR01053## ##STR01054## ##STR01055## ##STR01056## ##STR01057## ##STR01058## ##STR01059## ##STR01060##

[0337] In one or more embodiments, the fluorescent host may be represented by Formula FH-3:

##STR01061##

[0338] In Formula FH-3,

[0339] Ar.sub.1 may be a group represented by Formula 2:

##STR01062##

[0340] In Formula 2, Ar.sub.1 may include at least one cyano group,

[0341] A.sub.1 and A.sub.2 may each independently be a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group,

[0342] L.sub.1 may be an unsubstituted or substituted C.sub.5-C.sub.30 carbocyclic group or an unsubstituted or substituted C.sub.1-C.sub.30 heterocyclic group,

[0343] a1 may be 0, 1, 2, or 3,

[0344] when a1 is two or more, two or more of L.sub.1 may be identical to or different from each other,

[0345] m1 may be 0, 1, 2, or 3, and

[0346] Ar.sub.11 may be a group represented by Formula 4, Ar.sub.12 may be a group represented by Formula 5, and Ar.sub.13 may be a group represented by Formula 6:

##STR01063##

[0347] wherein, in the formulae above,

[0348] R.sub.1, R.sub.10, R.sub.20, R.sub.30, R.sub.40, R.sub.50, and R.sub.60 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted C.sub.1-C.sub.60heteroaryloxy group, a substituted or unsubstituted C.sub.1-C.sub.60heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), or —P(═O)(Q.sub.8)(Q.sub.9),

[0349] b1 may be an integer from 1 to 5,

[0350] when b1 is two or more, two or more of R.sub.1 may be identical to or different from each other,

[0351] b10 may be an integer from 1 to 8,

[0352] when b10 is two or more, two or more of R.sub.10 may be identical to or different from each other,

[0353] b20 and b30 may each independently be an integer from 1 to 4,

[0354] when b20 is 2 or more, two or more of R.sub.20 may be identical to or different from each other, and when b30 is 2 or more, two or more of R.sub.30 may be identical to or different from each other,

[0355] b40, b50, and b60 may each independently be an integer from 1 to 4,

[0356] when b40 is 2 or more, two or more of R.sub.40 may be identical to or different from each other, when b50 is 2 or more, two or more of R.sub.50 may be identical to or different from each other, and when b60 is 2 or more, two or more of R.sub.60 may be identical to or different from each other, and

[0357] * and *′ each indicate a binding site to a neighboring atom.

[0358] In one or more embodiments, the fluorescent host represented by Formula FH-3 may be a compound of Group FH3, embodiments of the present disclosure are not limited thereto:

##STR01064## ##STR01065## ##STR01066## ##STR01067## ##STR01068## ##STR01069## ##STR01070## ##STR01071## ##STR01072## ##STR01073## ##STR01074## ##STR01075## ##STR01076## ##STR01077## ##STR01078## ##STR01079## ##STR01080## ##STR01081## ##STR01082## ##STR01083## ##STR01084## ##STR01085## ##STR01086## ##STR01087## ##STR01088## ##STR01089## ##STR01090## ##STR01091## ##STR01092## ##STR01093## ##STR01094## ##STR01095## ##STR01096## ##STR01097## ##STR01098## ##STR01099## ##STR01100## ##STR01101## ##STR01102## ##STR01103## ##STR01104## ##STR01105## ##STR01106## ##STR01107## ##STR01108## ##STR01109## ##STR01110## ##STR01111## ##STR01112##

##STR01113## ##STR01114## ##STR01115## ##STR01116## ##STR01117## ##STR01118## ##STR01119## ##STR01120## ##STR01121## ##STR01122## ##STR01123## ##STR01124## ##STR01125## ##STR01126## ##STR01127## ##STR01128## ##STR01129## ##STR01130## ##STR01131## ##STR01132##

##STR01133## ##STR01134## ##STR01135## ##STR01136## ##STR01137## ##STR01138## ##STR01139## ##STR01140## ##STR01141## ##STR01142## ##STR01143## ##STR01144## ##STR01145## ##STR01146## ##STR01147## ##STR01148## ##STR01149## ##STR01150## ##STR01151##

[0359] In one or more embodiments, the fluorescent host may be represented by Formula FH-4:

##STR01152##

[0360] In Formula FH-4,

[0361] X.sub.1 may be O or Se,

[0362] Ar.sub.1 may be a group represented by Formula 1A, and Ar.sub.2 may be a group represented by Formula 1B:

##STR01153##

[0363] In Formulae 1A and 1B,

[0364] L.sub.1 and L.sub.2 may each independently be a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group,

[0365] a1 and a2 may each independently be an integer from 0 to 3,

[0366] when a1 is 2 or more, two or more of Li may be identical to or different from each other, and when a2 is 2 or more, two or more of L.sub.2 may be identical to or different from each other,

[0367] R.sub.1, R.sub.2, R.sub.10, R.sub.20, R.sub.30, and R.sub.40 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.60 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.60 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.1)(Q.sub.2), —Si(Q.sub.3)(Q.sub.4)(Q.sub.5), —B(Q.sub.6)(Q.sub.7), or —P(═O)(Q.sub.8)(Q.sub.9),

[0368] b1 and b2 may each independently be an integer from 1 to 5,

[0369] when b1 is 2 or more, two or more of R.sub.1 may be identical to or different from each other, and when b2 is 2 or more, two or more of R.sub.2 may be identical to or different from each other,

[0370] b10 and b20 may each independently an integer from 1 to 8,

[0371] b30 and b40 may each independently an integer from 1 to 3,

[0372] c1 and c2 may each independently be an integer from 1 to 8, and

[0373] the sum of b10 and c1 may be 9, and the sum of b20 and c2 may be 9.

[0374] In detail, the fluorescent host represented by Formula FH-4 may be a compound of Group FH4, embodiments of the present disclosure are not limited thereto:

##STR01154## ##STR01155## ##STR01156## ##STR01157## ##STR01158## ##STR01159## ##STR01160## ##STR01161## ##STR01162## ##STR01163## ##STR01164## ##STR01165## ##STR01166## ##STR01167## ##STR01168## ##STR01169## ##STR01170## ##STR01171## ##STR01172## ##STR01173## ##STR01174## ##STR01175## ##STR01176## ##STR01177## ##STR01178## ##STR01179## ##STR01180## ##STR01181## ##STR01182## ##STR01183## ##STR01184## ##STR01185## ##STR01186## ##STR01187## ##STR01188## ##STR01189## ##STR01190## ##STR01191## ##STR01192## ##STR01193## ##STR01194## ##STR01195## ##STR01196## ##STR01197## ##STR01198## ##STR01199## ##STR01200## ##STR01201## ##STR01202## ##STR01203## ##STR01204## ##STR01205## ##STR01206## ##STR01207## ##STR01208## ##STR01209## ##STR01210## ##STR01211## ##STR01212## ##STR01213## ##STR01214## ##STR01215## ##STR01216## ##STR01217## ##STR01218## ##STR01219## ##STR01220## ##STR01221## ##STR01222## ##STR01223## ##STR01224## ##STR01225## ##STR01226## ##STR01227## ##STR01228## ##STR01229## ##STR01230## ##STR01231##

##STR01232## ##STR01233## ##STR01234## ##STR01235## ##STR01236## ##STR01237## ##STR01238## ##STR01239## ##STR01240## ##STR01241## ##STR01242## ##STR01243## ##STR01244## ##STR01245## ##STR01246## ##STR01247## ##STR01248## ##STR01249## ##STR01250## ##STR01251## ##STR01252## ##STR01253## ##STR01254## ##STR01255## ##STR01256## ##STR01257## ##STR01258## ##STR01259## ##STR01260## ##STR01261## ##STR01262## ##STR01263## ##STR01264## ##STR01265## ##STR01266## ##STR01267## ##STR01268## ##STR01269## ##STR01270## ##STR01271## ##STR01272## ##STR01273## ##STR01274## ##STR01275## ##STR01276## ##STR01277## ##STR01278##

##STR01279## ##STR01280## ##STR01281## ##STR01282## ##STR01283## ##STR01284## ##STR01285## ##STR01286## ##STR01287## ##STR01288## ##STR01289## ##STR01290## ##STR01291## ##STR01292## ##STR01293## ##STR01294## ##STR01295## ##STR01296## ##STR01297## ##STR01298## ##STR01299## ##STR01300## ##STR01301## ##STR01302## ##STR01303## ##STR01304## ##STR01305## ##STR01306## ##STR01307## ##STR01308## ##STR01309##

##STR01310## ##STR01311## ##STR01312## ##STR01313## ##STR01314## ##STR01315## ##STR01316## ##STR01317## ##STR01318## ##STR01319## ##STR01320## ##STR01321## ##STR01322## ##STR01323## ##STR01324## ##STR01325## ##STR01326## ##STR01327## ##STR01328## ##STR01329##

##STR01330## ##STR01331## ##STR01332## ##STR01333## ##STR01334## ##STR01335## ##STR01336## ##STR01337## ##STR01338## ##STR01339## ##STR01340## ##STR01341## ##STR01342## ##STR01343## ##STR01344## ##STR01345## ##STR01346## ##STR01347## ##STR01348## ##STR01349## ##STR01350## ##STR01351## ##STR01352## ##STR01353## ##STR01354## ##STR01355## ##STR01356## ##STR01357## ##STR01358## ##STR01359## ##STR01360## ##STR01361## ##STR01362## ##STR01363## ##STR01364##

##STR01365## ##STR01366## ##STR01367## ##STR01368## ##STR01369## ##STR01370## ##STR01371## ##STR01372## ##STR01373## ##STR01374## ##STR01375## ##STR01376## ##STR01377## ##STR01378## ##STR01379## ##STR01380## ##STR01381## ##STR01382## ##STR01383## ##STR01384## ##STR01385## ##STR01386## ##STR01387## ##STR01388## ##STR01389## ##STR01390## ##STR01391## ##STR01392## ##STR01393## ##STR01394## ##STR01395## ##STR01396## ##STR01397## ##STR01398## ##STR01399## ##STR01400## ##STR01401## ##STR01402## ##STR01403## ##STR01404## ##STR01405## ##STR01406## ##STR01407## ##STR01408## ##STR01409## ##STR01410## ##STR01411## ##STR01412## ##STR01413## ##STR01414## ##STR01415## ##STR01416## ##STR01417## ##STR01418## ##STR01419## ##STR01420## ##STR01421## ##STR01422## ##STR01423## ##STR01424## ##STR01425## ##STR01426## ##STR01427## ##STR01428## ##STR01429## ##STR01430## ##STR01431## ##STR01432## ##STR01433## ##STR01434## ##STR01435## ##STR01436##

##STR01437## ##STR01438## ##STR01439## ##STR01440## ##STR01441## ##STR01442## ##STR01443## ##STR01444## ##STR01445## ##STR01446## ##STR01447## ##STR01448## ##STR01449## ##STR01450## ##STR01451## ##STR01452## ##STR01453## ##STR01454## ##STR01455## ##STR01456## ##STR01457## ##STR01458## ##STR01459## ##STR01460## ##STR01461## ##STR01462## ##STR01463## ##STR01464## ##STR01465## ##STR01466## ##STR01467## ##STR01468## ##STR01469## ##STR01470## ##STR01471## ##STR01472## ##STR01473## ##STR01474## ##STR01475## ##STR01476## ##STR01477## ##STR01478## ##STR01479##

##STR01480## ##STR01481## ##STR01482## ##STR01483## ##STR01484## ##STR01485## ##STR01486## ##STR01487## ##STR01488## ##STR01489## ##STR01490## ##STR01491## ##STR01492## ##STR01493## ##STR01494## ##STR01495## ##STR01496## ##STR01497## ##STR01498## ##STR01499## ##STR01500## ##STR01501## ##STR01502## ##STR01503## ##STR01504## ##STR01505## ##STR01506## ##STR01507## ##STR01508## ##STR01509## ##STR01510## ##STR01511## ##STR01512##

##STR01513## ##STR01514## ##STR01515## ##STR01516## ##STR01517## ##STR01518## ##STR01519## ##STR01520## ##STR01521## ##STR01522## ##STR01523## ##STR01524## ##STR01525## ##STR01526## ##STR01527## ##STR01528## ##STR01529## ##STR01530## ##STR01531## ##STR01532## ##STR01533## ##STR01534## ##STR01535## ##STR01536## ##STR01537## ##STR01538## ##STR01539## ##STR01540## ##STR01541## ##STR01542## ##STR01543## ##STR01544## ##STR01545## ##STR01546## ##STR01547## ##STR01548## ##STR01549## ##STR01550## ##STR01551## ##STR01552## ##STR01553## ##STR01554## ##STR01555## ##STR01556## ##STR01557## ##STR01558## ##STR01559## ##STR01560## ##STR01561## ##STR01562## ##STR01563## ##STR01564## ##STR01565## ##STR01566## ##STR01567## ##STR01568## ##STR01569## ##STR01570## ##STR01571## ##STR01572## ##STR01573## ##STR01574## ##STR01575##

##STR01576## ##STR01577## ##STR01578## ##STR01579## ##STR01580## ##STR01581## ##STR01582## ##STR01583## ##STR01584## ##STR01585## ##STR01586## ##STR01587## ##STR01588## ##STR01589## ##STR01590## ##STR01591## ##STR01592## ##STR01593## ##STR01594## ##STR01595## ##STR01596## ##STR01597## ##STR01598## ##STR01599## ##STR01600## ##STR01601## ##STR01602## ##STR01603## ##STR01604## ##STR01605## ##STR01606## ##STR01607## ##STR01608## ##STR01609## ##STR01610## ##STR01611## ##STR01612## ##STR01613## ##STR01614## ##STR01615## ##STR01616## ##STR01617## ##STR01618## ##STR01619## ##STR01620## ##STR01621## ##STR01622## ##STR01623## ##STR01624## ##STR01625## ##STR01626## ##STR01627## ##STR01628## ##STR01629## ##STR01630## ##STR01631## ##STR01632## ##STR01633##

##STR01634## ##STR01635## ##STR01636## ##STR01637## ##STR01638## ##STR01639## ##STR01640## ##STR01641## ##STR01642## ##STR01643## ##STR01644## ##STR01645## ##STR01646## ##STR01647## ##STR01648## ##STR01649## ##STR01650## ##STR01651## ##STR01652## ##STR01653## ##STR01654## ##STR01655## ##STR01656## ##STR01657## ##STR01658## ##STR01659## ##STR01660## ##STR01661## ##STR01662## ##STR01663## ##STR01664## ##STR01665## ##STR01666## ##STR01667## ##STR01668## ##STR01669## ##STR01670## ##STR01671## ##STR01672## ##STR01673## ##STR01674## ##STR01675## ##STR01676## ##STR01677## ##STR01678## ##STR01679##

[0375] When the host is a mixture of the electron-transporting host and the hole-transporting host, a weight ratio of the electron-transporting host to the hole-transporting host may be in a range of about 1:9 to about 9:1, for example, about 2:8 to about 8:2, for example, about 4:6 to about 6:4, for example, about 5:5. When the weight ratio of the electron-transporting host to the hole-transporting host is within the ranges above, the hole-and-electron-transporting balance in the emission layer 15 may be achieved.

[Dopant in Emission Layer 15]

[0376] The dopant included in the emission layer 15 may include the heterocyclic compound.

[Sensitizer in Emission Layer 15]

[0377] In an embodiment, the sensitizer included in the emission layer 15 may include a phosphorescent sensitizer including at least one metal a first-row transition metal, a second-row transition metal, a third-row transition metal, or a combination thereof, of the Periodic Table of Elements.

[0378] In one or more embodiments, the sensitizer may include an organic ligand L.sub.1 and at least one metal M11 of a first-row transition metal, a second-row transition metal, a third-row transition metal of the Periodic Table of Elements, wherein L.sub.1 and M11 may form 1, 2, 3, or 4 cyclometallated rings.

[0379] In one or more embodiments, the sensitizer may include an organometallic compound represented by Formula 103:

M.sub.11(L.sub.11).sub.n11(L.sub.12).sub.n12  Formula 103

[0380] wherein, in Formula 103,

[0381] M.sub.11 may be a first-row transition metal, a second-row transition metal, or a third-row transition metal of the Periodic Table of Elements,

[0382] L.sub.11 may be a ligand represented by one of Formulae 1-1 to 1-4,

[0383] L.sub.12 may be a monodentate ligand or a bidentate ligand,

[0384] n11 may be 1, and

[0385] n12 may be 0, 1, or 2,

##STR01680##

[0386] In Formulae 1-1 to 1-4,

[0387] A.sub.1 to A.sub.4 may each independently be a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group, a substituted or unsubstituted C.sub.1-C.sub.33 heterocyclic group, or a non-cyclic group,

[0388] Y.sub.11 to Y.sub.14 may each independently be a chemical bond, O, S, N(R.sub.91), B(R.sub.91), P(R.sub.91), or C(R.sub.91)(R.sub.92),

[0389] T.sub.1 to T.sub.4 may each independently be a single bond, a double bond, *—N(R.sub.93)—*′, *—O—*′, *—C(═Q)-*′, *—S(═O)—*′, *—S(═O).sub.2—*′, *—C(R.sub.93)═*′, *═C(R.sub.93)—*′, *—C(R.sub.93)═C(R.sub.94)—*′, *—C(═S)—*′, or *—C≡C—*′,

[0390] a substituent of the substituted C.sub.5-C.sub.30 carbocyclic group, a substituent of substituted C.sub.1-C.sub.30 heterocyclic group, and R.sub.91 to R.sub.94 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, —SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent aromatic condensed polycyclic group, a substituted or unsubstituted monovalent aromatic condensed heteropolycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —Ge(Q.sub.1)(Q.sub.2)(Q.sub.3), —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —B(Q.sub.1)(Q.sub.2), —N(Q.sub.1)(Q.sub.2), —P(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), —P(═O)(Q.sub.1)(Q.sub.2), or —P(═S)(Q.sub.1)(Q.sub.2), wherein each of a substituent of the substituted C.sub.5-C.sub.30 carbocyclic group and a substituent of substituted C.sub.1-C.sub.30 heterocyclic group may not be hydrogen,

[0391] *.sub.1, *.sub.2, *.sub.3, and *.sub.4 each indicate a binding site to M.sub.11, and

[0392] Q.sub.1 to Q.sub.3 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkyl heteroaryl group, a C.sub.1-C.sub.60 heteroaryloxy group, a C.sub.1-C.sub.60 heteroarylthio group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C.sub.1-C.sub.60 alkyl group that is substituted with at least one deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof, or a C.sub.6-C.sub.60 aryl group that is substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof.

[0393] In one or more embodiments, the sensitizer may be a compound of Groups I to X, but embodiments of the present disclosure are not limited thereto:

##STR01681## ##STR01682## ##STR01683##

##STR01684## ##STR01685## ##STR01686## ##STR01687## ##STR01688## ##STR01689## ##STR01690## ##STR01691## ##STR01692## ##STR01693## ##STR01694## ##STR01695## ##STR01696## ##STR01697## ##STR01698## ##STR01699## ##STR01700## ##STR01701## ##STR01702## ##STR01703## ##STR01704## ##STR01705## ##STR01706## ##STR01707## ##STR01708## ##STR01709## ##STR01710## ##STR01711## ##STR01712## ##STR01713##

##STR01714## ##STR01715## ##STR01716## ##STR01717## ##STR01718## ##STR01719## ##STR01720## ##STR01721## ##STR01722## ##STR01723## ##STR01724## ##STR01725## ##STR01726## ##STR01727## ##STR01728## ##STR01729## ##STR01730## ##STR01731## ##STR01732## ##STR01733## ##STR01734## ##STR01735## ##STR01736## ##STR01737## ##STR01738## ##STR01739## ##STR01740## ##STR01741## ##STR01742## ##STR01743## ##STR01744## ##STR01745## ##STR01746## ##STR01747## ##STR01748## ##STR01749## ##STR01750## ##STR01751## ##STR01752## ##STR01753## ##STR01754## ##STR01755## ##STR01756##

##STR01757## ##STR01758## ##STR01759## ##STR01760## ##STR01761## ##STR01762## ##STR01763## ##STR01764## ##STR01765## ##STR01766## ##STR01767## ##STR01768## ##STR01769## ##STR01770## ##STR01771## ##STR01772## ##STR01773## ##STR01774## ##STR01775## ##STR01776## ##STR01777## ##STR01778## ##STR01779## ##STR01780## ##STR01781## ##STR01782## ##STR01783## ##STR01784## ##STR01785## ##STR01786## ##STR01787## ##STR01788## ##STR01789## ##STR01790## ##STR01791## ##STR01792## ##STR01793## ##STR01794##

##STR01795## ##STR01796## ##STR01797## ##STR01798## ##STR01799## ##STR01800## ##STR01801## ##STR01802## ##STR01803## ##STR01804## ##STR01805## ##STR01806## ##STR01807## ##STR01808## ##STR01809## ##STR01810## ##STR01811## ##STR01812## ##STR01813## ##STR01814## ##STR01815## ##STR01816## ##STR01817## ##STR01818## ##STR01819## ##STR01820## ##STR01821## ##STR01822## ##STR01823## ##STR01824## ##STR01825## ##STR01826## ##STR01827## ##STR01828## ##STR01829## ##STR01830## ##STR01831## ##STR01832## ##STR01833## ##STR01834## ##STR01835## ##STR01836## ##STR01837## ##STR01838## ##STR01839## ##STR01840## ##STR01841##

##STR01842## ##STR01843## ##STR01844## ##STR01845## ##STR01846## ##STR01847## ##STR01848## ##STR01849## ##STR01850## ##STR01851## ##STR01852## ##STR01853## ##STR01854## ##STR01855## ##STR01856## ##STR01857## ##STR01858## ##STR01859## ##STR01860## ##STR01861## ##STR01862## ##STR01863##

##STR01864## ##STR01865## ##STR01866##

[0394] Group V

[0395] a compound represented by Formula A:

(L.sub.101).sub.n101-M.sub.101-(L.sub.102).sub.m101  Formula A

[0396] wherein, in Formula A, L.sub.101, n101, M.sub.101, L.sub.102, and m101 may respectively be the same as described in Tables 2 to 4:

TABLE-US-00002 TABLE 2 Compound name L.sub.101 n101 M.sub.101 L.sub.102 m101 BD001 LM1 3 Ir — 0 BD002 LM2 3 Ir — 0 BD003 LM3 3 Ir — 0 BD004 LM4 3 Ir — 0 BD005 LM5 3 Ir — 0 BD006 LM6 3 Ir — 0 BD007 LM7 3 Ir — 0 BD008 LM8 3 Ir — 0 BD009 LM9 3 Ir — 0 BD010 LM10 3 Ir — 0 BD011 LM11 3 Ir — 0 BD012 LM12 3 Ir — 0 BD013 LM13 3 Ir — 0 BD014 LM14 3 Ir — 0 BD015 LM15 3 Ir — 0 BD016 LM16 3 Ir — 0 BD017 LM17 3 Ir — 0 BD018 LM18 3 Ir — 0 BD019 LM19 3 Ir — 0 BD020 LM20 3 Ir — 0 BD021 LM21 3 Ir — 0 BD022 LM22 3 Ir — 0 BD023 LM23 3 Ir — 0 BD024 LM24 3 Ir — 0 BD025 LM25 3 Ir — 0 BD026 LM26 3 Ir — 0 BD027 LM27 3 Ir — 0 BD028 LM28 3 Ir — 0 BD029 LM29 3 Ir — 0 BD030 LM30 3 Ir — 0 BD031 LM31 3 Ir — 0 BD032 LM32 3 Ir — 0 BD033 LM33 3 Ir — 0 BD034 LM34 3 Ir — 0 BD035 LM35 3 Ir — 0 BD036 LM36 3 Ir — 0 BD037 LM37 3 Ir — 0 BD038 LM38 3 Ir — 0 BD039 LM39 3 Ir — 0 BD040 LM40 3 Ir — 0 BD041 LM41 3 Ir — 0 BD042 LM42 3 Ir — 0 BD043 LM43 3 Ir — 0 BD044 LM44 3 Ir — 0 BD045 LM45 3 Ir — 0 BD046 LM46 3 Ir — 0 BD047 LM47 3 Ir — 0 BD048 LM48 3 Ir — 0 BD049 LM49 3 Ir — 0 BD050 LM50 3 Ir — 0 BD051 LM51 3 Ir — 0 BD052 LM52 3 Ir — 0 BD053 LM53 3 Ir — 0 BD054 LM54 3 Ir — 0 BD055 LM55 3 Ir — 0 BD056 LM56 3 Ir — 0 BD057 LM57 3 Ir — 0 BD058 LM58 3 Ir — 0 BD059 LM59 3 Ir — 0 BD060 LM60 3 Ir — 0 BD061 LM61 3 Ir — 0 BD062 LM62 3 Ir — 0 BD063 LM63 3 Ir — 0 BD064 LM64 3 Ir — 0 BD065 LM65 3 Ir — 0 BD066 LM66 3 Ir — 0 BD067 LM67 3 Ir — 0 BD068 LM68 3 Ir — 0 BD069 LM69 3 Ir — 0 BD070 LM70 3 Ir — 0 BD071 LM71 3 Ir — 0 BD072 LM72 3 Ir — 0 BD073 LM73 3 Ir — 0 BD074 LM74 3 Ir — 0 BD075 LM75 3 Ir — 0 BD076 LM76 3 Ir — 0 BD077 LM77 3 Ir — 0 BD078 LM78 3 Ir — 0 BD079 LM79 3 Ir — 0 BD080 LM80 3 Ir — 0 BD081 LM81 3 Ir — 0 BD082 LM82 3 Ir — 0 BD083 LM83 3 Ir — 0 BD084 LM84 3 Ir — 0 BD085 LM85 3 Ir — 0 BD086 LM86 3 Ir — 0 BD087 LM87 3 Ir — 0 BD088 LM88 3 Ir — 0 BD089 LM89 3 Ir — 0 BD090 LM90 3 Ir — 0 BD091 LM91 3 Ir — 0 BD092 LM92 3 Ir — 0 BD093 LM93 3 Ir — 0 BD094 LM94 3 Ir — 0 BD095 LM95 3 Ir — 0 BD096 LM96 3 Ir — 0 BD097 LM97 3 Ir — 0 BD098 LM98 3 Ir — 0 BD099 LM99 3 Ir — 0 BD100 LM100 3 Ir — 0

TABLE-US-00003 TABLE 3 Compound name L.sub.101 n101 M.sub.101 L.sub.102 m101 BD101 LM101 3 Ir — 0 BD102 LM102 3 Ir — 0 BD103 LM103 3 Ir — 0 BD104 LM104 3 Ir — 0 BD105 LM105 3 Ir — 0 BD106 LM106 3 Ir — 0 BD107 LM107 3 Ir — 0 BD108 LM108 3 Ir — 0 BD109 LM109 3 Ir — 0 BD110 LM110 3 Ir — 0 BD111 LM111 3 Ir — 0 BD112 LM112 3 Ir — 0 BD113 LM113 3 Ir — 0 BD114 LM114 3 Ir — 0 BD115 LM115 3 Ir — 0 BD116 LM116 3 Ir — 0 BD117 LM117 3 Ir — 0 BD118 LM118 3 Ir — 0 BD119 LM119 3 Ir — 0 BD120 LM120 3 Ir — 0 BD121 LM121 3 Ir — 0 BD122 LM122 3 Ir — 0 BD123 LM123 3 Ir — 0 BD124 LM124 3 Ir — 0 BD125 LM125 3 Ir — 0 BD126 LM126 3 Ir — 0 BD127 LM127 3 Ir — 0 BD128 LM128 3 Ir — 0 BD129 LM129 3 Ir — 0 BD130 LM130 3 Ir — 0 BD131 LM131 3 Ir — 0 BD132 LM132 3 Ir — 0 BD133 LM133 3 Ir — 0 BD134 LM134 3 Ir — 0 BD135 LM135 3 Ir — 0 BD136 LM136 3 Ir — 0 BD137 LM137 3 Ir — 0 BD138 LM138 3 Ir — 0 BD139 LM139 3 Ir — 0 BD140 LM140 3 Ir — 0 BD141 LM141 3 Ir — 0 BD142 LM142 3 Ir — 0 BD143 LM143 3 Ir — 0 BD144 LM144 3 Ir — 0 BD145 LM145 3 Ir — 0 BD146 LM146 3 Ir — 0 BD147 LM147 3 Ir — 0 BD148 LM148 3 Ir — 0 BD149 LM149 3 Ir — 0 BD150 LM150 3 Ir — 0 BD151 LM151 3 Ir — 0 BD152 LM152 3 Ir — 0 BD153 LM153 3 Ir — 0 BD154 LM154 3 Ir — 0 BD155 LM155 3 Ir — 0 BD156 LM156 3 Ir — 0 BD157 LM157 3 Ir — 0 BD158 LM158 3 Ir — 0 BD159 LM159 3 Ir — 0 BD160 LM160 3 Ir — 0 BD161 LM161 3 Ir — 0 BD162 LM162 3 Ir — 0 BD163 LM163 3 Ir — 0 BD164 LM164 3 Ir — 0 BD165 LM165 3 Ir — 0 BD166 LM166 3 Ir — 0 BD167 LM167 3 Ir — 0 BD168 LM168 3 Ir — 0 BD169 LM169 3 Ir — 0 BD170 LM170 3 Ir — 0 BD171 LM171 3 Ir — 0 BD172 LM172 3 Ir — 0 BD173 LM173 3 Ir — 0 BD174 LM174 3 Ir — 0 BD175 LM175 3 Ir — 0 BD176 LM176 3 Ir — 0 BD177 LM177 3 Ir — 0 BD178 LM178 3 Ir — 0 BD179 LM179 3 Ir — 0 BD180 LM180 3 Ir — 0 BD181 LM181 3 Ir — 0 BD182 LM182 3 Ir — 0 BD183 LM183 3 Ir — 0 BD184 LM184 3 Ir — 0 BD185 LM185 3 Ir — 0 BD186 LM186 3 Ir — 0 BD187 LM187 3 Ir — 0 BD188 LM188 3 Ir — 0 BD189 LM189 3 Ir — 0 BD190 LM190 3 Ir — 0 BD191 LM191 3 Ir — 0 BD192 LM192 3 Ir — 0 BD193 LM193 3 Ir — 0 BD194 LM194 3 Ir — 0 BD195 LM195 3 Ir — 0 BD196 LM196 3 Ir — 0 BD197 LM197 3 Ir — 0 BD198 LM198 3 Ir — 0 BD199 LM199 3 Ir — 0 BD200 LM200 3 Ir — 0

TABLE-US-00004 TABLE 4 Compound name L.sub.101 n101 M.sub.101 L.sub.102 m101 BD201 LM201 3 Ir — 0 BD202 LM202 3 Ir — 0 BD203 LM203 3 Ir — 0 BD204 LM204 3 Ir — 0 BD205 LM205 3 Ir — 0 BD206 LM206 3 Ir — 0 BD207 LM207 3 Ir — 0 BD208 LM208 3 Ir — 0 BD209 LM209 3 Ir — 0 BD210 LM210 3 Ir — 0 BD211 LM211 3 Ir — 0 BD212 LM212 3 Ir — 0 BD213 LM213 3 Ir — 0 BD214 LM214 3 Ir — 0 BD215 LM215 3 Ir — 0 BD216 LM216 3 Ir — 0 BD217 LM217 3 Ir — 0 BD218 LM218 3 Ir — 0 BD219 LM219 3 Ir — 0 BD220 LM220 3 Ir — 0 BD221 LM221 3 Ir — 0 BD222 LM222 3 Ir — 0 BD223 LM223 3 Ir — 0 BD224 LM224 3 Ir — 0 BD225 LM225 3 Ir — 0 BD226 LM226 3 Ir — 0 BD227 LM227 3 Ir — 0 BD228 LM228 3 Ir — 0 BD229 LM229 3 Ir — 0 BD230 LM230 3 Ir — 0 BD231 LM231 3 Ir — 0 BD232 LM232 3 Ir — 0 BD233 LM233 3 Ir — 0 BD234 LM234 3 Ir — 0 BD235 LM235 3 Ir — 0 BD236 LM236 3 Ir — 0 BD237 LM237 3 Ir — 0 BD238 LM238 3 Ir — 0 BD239 LM239 3 Ir — 0 BD240 LM240 3 Ir — 0 BD241 LM241 3 Ir — 0 BD242 LM242 3 Ir — 0 BD243 LM243 3 Ir — 0 BD244 LFM1 3 Ir — 0 BD245 LFM2 3 Ir — 0 BD246 LFM3 3 Ir — 0 BD247 LFM4 3 Ir — 0 BD248 LFM5 3 Ir — 0 BD249 LFM6 3 Ir — 0 BD250 LFM7 3 Ir — 0 BD251 LFP1 3 Ir — 0 BD252 LFP2 3 Ir — 0 BD253 LFP3 3 Ir — 0 BD254 LFP4 3 Ir — 0 BD255 LFP5 3 Ir — 0 BD256 LFP6 3 Ir — 0 BD257 LFP7 3 Ir — 0 BD258 LM47 2 Ir AN1 1 BD259 LM47 2 Ir AN2 1 BD260 LM47 2 Ir AN3 1 BD261 LM47 2 Ir AN4 1 BD262 LM47 2 Ir AN5 1 BD263 LM11 2 Pt — 0 BD264 LM13 2 Pt — 0 BD265 LM15 2 Pt — 0 BD266 LM45 2 Pt — 0 BD267 LM47 2 Pt — 0 BD268 LM49 2 Pt — 0 BD269 LM98 2 Pt — 0 BD270 LM100 2 Pt — 0 BD271 LM102 2 Pt — 0 BD272 LM132 2 Pt — 0 BD273 LM134 2 Pt — 0 BD274 LM136 2 Pt — 0 BD275 LM151 2 Pt — 0 BD276 LM153 2 Pt — 0 BD277 LM158 2 Pt — 0 BD278 LM180 2 Pt — 0 BD279 LM182 2 Pt — 0 BD280 LM187 2 Pt — 0 BD281 LM201 2 Pt — 0 BD282 LM206 2 Pt — 0 BD283 LM211 2 Pt — 0 BD284 LM233 2 Pt — 0 BD285 LM235 2 Pt — 0 BD286 LM240 2 Pt — 0 BD287 LFM5 2 Pt — 0 BD288 LFM6 2 Pt — 0 BD289 LFM7 2 Pt — 0 BD290 LFP5 2 Pt — 0 BD291 LFP6 2 Pt — 0 BD292 LFP7 2 Pt — 0 BD293 LM47 1 Pt AN1 1 BD294 LM47 1 Pt AN2 1 BD295 LM47 1 Pt AN3 1 BD296 LM47 1 Pt AN4 1 BD297 LM47 1 Pt AN5 1

[0397] Referring to Tables 2 to 4, LM1 to LM243 may respectively be understood by referring to Formulae 1-1 to 1-3 and Tables 5 to 7:

##STR01867##

TABLE-US-00005 TABLE 5 Formula 1-1 Ligand R.sub.11 R.sub.12 R.sub.13 R.sub.14 R.sub.15 R.sub.16 R.sub.17 R.sub.18 R.sub.19 R.sub.20 LM1 X1 H X3 H X1 H H H H D LM2 X1 H X3 H X1 H H H D H LM3 X1 H X3 H X1 H H H D D LM4 Y1 H X3 H Y1 H H H D D LM5 Y2 H X3 H Y2 H H H D D LM6 Y3 H X3 H Y3 H H H D D LM7 Y3 D X3 D Y3 H H H D D LM8 Y3 D X3 D Y3 D H H D D LM9 Y3 D X3 D Y3 D D H D D LM10 Y3 D X3 D Y3 D D D D D LM11 Y3 D Y11 D Y3 D D D D D LM12 Y3 D Y11 D Y3 H X1 H D D LM13 Y3 D Y11 D Y3 D Y3 D D D LM14 Y3 D Y11 D Y3 H X4 H D D LM15 Y3 D Y11 D Y3 D Y12 D D D LM16 X2 H X3 H X2 H H H H D LM17 X2 H X3 H X2 H H H D H LM18 X2 H X3 H X2 H H H D D LM19 Y4 H X3 H Y4 H H H D D LM20 Y5 H X3 H Y5 H H H D D LM21 Y6 H X3 H Y6 H H H D D LM22 Y7 H X3 H Y7 H H H D D LM23 Y8 H X3 H Y8 H H H D D LM24 Y9 H X3 H Y9 H H H D D LM25 Y10 H X3 H Y10 H H H D D LM26 Y10 D X3 D Y10 H H H D D LM27 Y10 D X3 D Y10 D H H D D LM28 Y10 D X3 D Y10 D D H D D LM29 Y10 D X3 D Y10 D D D D D LM30 Y10 D Y11 D Y10 D D D D D LM31 Y10 D Y11 D Y10 H X1 H D D LM32 Y10 D Y11 D Y10 D Y3 D D D LM33 Y10 D Y11 D Y10 H X4 H D D LM34 Y10 D Y11 D Y10 D Y12 D D D LM35 X1 H X4 H X1 H H H H D LM36 X1 H X4 H X1 H H H D H LM37 X1 H X4 H X1 H H H D D LM38 Y1 H X4 H Y1 H H H D D LM39 Y2 H X4 H Y2 H H H D D LM40 Y3 H X4 H Y3 H H H D D LM41 Y3 D X4 D Y3 H H H D D LM42 Y3 D X4 D Y3 D H H D D LM43 Y3 D X4 D Y3 D D H D D LM44 Y3 D X4 D Y3 D D D D D LM45 Y3 D Y12 D Y3 D D D D D LM46 Y3 D Y12 D Y3 H X1 H D D LM47 Y3 D Y12 D Y3 D Y3 D D D LM48 Y3 D Y12 D Y3 H X4 H D D LM49 Y3 D Y12 D Y3 D Y12 D D D LM50 X2 H X4 H X2 H H H H D LM51 X2 H X4 H X2 H H H D H LM52 X2 H X4 H X2 H H H D D LM53 Y4 H X4 H Y4 H H H D D LM54 Y5 H X4 H Y5 H H H D D LM55 Y6 H X4 H Y6 H H H D D LM56 Y7 H X4 H Y7 H H H D D LM57 Y8 H X4 H Y8 H H H D D LM58 Y9 H X4 H Y9 H H H D D LM59 Y10 H X4 H Y10 H H H D D LM60 Y10 D X4 D Y10 H H H D D LM61 Y10 D X4 D Y10 D H H D D LM62 Y10 D X4 D Y10 D D H D D LM63 Y10 D X4 D Y10 D D D D D LM64 Y10 D Y12 D Y10 D D D D D LM65 Y10 D Y12 D Y10 H X1 H D D LM66 Y10 D Y12 D Y10 D Y3 D D D LM67 Y10 D Y12 D Y10 H X4 H D D LM68 Y10 D Y12 D Y10 D Y12 D D D LM69 X1 H X5 H X1 H H H H D LM70 X1 H X5 H X1 H H H D H LM71 X1 H X5 H X1 H H H D D LM72 Y1 H X5 H Y1 H H H D D LM73 Y2 H X5 H Y2 H H H D D LM74 Y3 H X5 H Y3 H H H D D LM75 Y3 D X5 D Y3 H H H D D LM76 Y3 D X5 D Y3 D H H D D LM77 Y3 D X5 D Y3 D D H D D LM78 Y3 D X5 D Y3 D D D D D LM79 Y3 D Y13 D Y3 D D D D D LM80 Y3 D Y13 D Y3 H X1 H D D LM81 Y3 D Y13 D Y3 D Y3 D D D LM82 Y3 D Y13 D Y3 H X4 H D D LM83 Y3 D Y13 D Y3 D Y12 D D D LM84 X2 H X5 H X2 H H H H D LM85 X2 H X5 H X2 H H H D H LM86 X2 H X5 H X2 H H H D D LM87 Y4 H X5 H Y4 H H H D D LM88 Y5 H X5 H Y5 H H H D D LM89 Y6 H X5 H Y6 H H H D D LM90 Y7 H X5 H Y7 H H H D D LM91 Y8 H X5 H Y8 H H H D D LM92 Y9 H X5 H Y9 H H H D D LM93 Y10 H X5 H Y10 H H H D D LM94 Y10 D X5 D Y10 H H H D D LM95 Y10 D X5 D Y10 D H H D D LM96 Y10 D X5 D Y10 D D H D D LM97 Y10 D X5 D Y10 D D D D D LM98 Y10 D Y13 D Y10 D D D D D LM99 Y10 D Y13 D Y10 H X1 H D D LM100 Y10 D Y13 D Y10 D Y3 D D D LM101 Y10 D Y13 D Y10 H X4 H D D LM102 Y10 D Y13 D Y10 D Y12 D D D LM103 X1 H X6 H X1 H H H H D LM104 X1 H X6 H X1 H H H D H LM105 X1 H X6 H X1 H H H D D LM106 Y1 H X6 H Y1 H H H D D LM107 Y2 H X6 H Y2 H H H D D LM108 Y3 H X6 H Y3 H H H D D LM109 Y3 D X6 D Y3 H H H D D LM110 Y3 D X6 D Y3 D H H D D LM111 Y3 D X6 D Y3 D D H D D LM112 Y3 D X6 D Y3 D D D D D LM113 Y3 D Y14 D Y3 D D D D D LM114 Y3 D Y14 D Y3 H X1 H D D LM115 Y3 D Y14 D Y3 D Y3 D D D LM116 Y3 D Y14 D Y3 H X4 H D D LM117 Y3 D Y14 D Y3 D Y12 D D D LM118 X2 H X6 H X2 H H H H D LM119 X2 H X6 H X2 H H H D H LM120 X2 H X6 H X2 H H H D D LM121 Y4 H X6 H Y4 H H H D D LM122 Y5 H X6 H Y5 H H H D D LM123 Y6 H X6 H Y6 H H H D D LM124 Y7 H X6 H Y7 H H H D D LM125 Y8 H X6 H Y8 H H H D D LM126 Y9 H X6 H Y9 H H H D D LM127 Y10 H X6 H Y10 H H H D D LM128 Y10 D X6 D Y10 H H H D D LM129 Y10 D X6 D Y10 D H H D D LM130 Y10 D X6 D Y10 D D H D D LM131 Y10 D X6 D Y10 D D D D D LM132 Y10 D Y14 D Y10 D D D D D LM133 Y10 D Y14 D Y10 H X1 H D D LM134 Y10 D Y14 D Y10 D Y3 D D D LM135 Y10 D Y14 D Y10 H X4 H D D LM136 Y10 D Y14 D Y10 D Y12 D D D LM137 X1 H X7 H X1 H H H H D LM138 X1 H X7 H X1 H H H D H LM139 X1 H X7 H X1 H H H D D LM140 Y1 H X7 H Y1 H H H D D LM141 Y2 H X7 H Y2 H H H D D LM142 Y3 H X7 H Y3 H H H D D LM143 Y3 D X7 D Y3 H H H D D LM144 Y3 D X7 D Y3 D H H D D LM145 Y3 D X7 D Y3 D D H D D LM146 Y3 D X7 D Y3 D D D D D LM147 Y3 D X8 D Y3 D D D D D LM148 Y3 D Y16 D Y3 D D D D D LM149 Y3 D Y17 D Y3 D D D D D LM150 Y3 D Y18 D Y3 D D D D D LM151 Y3 D Y15 D Y3 D D D D D LM152 Y3 D Y15 D Y3 H X1 H D D LM153 Y3 D Y15 D Y3 D Y3 D D D LM154 Y3 D Y16 D Y3 D Y3 D D D LM155 Y3 D Y17 D Y3 D Y3 D D D LM156 Y3 D Y18 D Y3 D Y3 D D D LM157 Y3 D Y15 D Y3 H X4 H D D LM158 Y3 D Y15 D Y3 D Y12 D D D LM159 Y3 D Y16 D Y3 D Y12 D D D LM160 Y3 D Y17 D Y3 D Y12 D D D LM161 Y3 D Y18 D Y3 D Y12 D D D LM162 X2 H X7 H X2 H H H H D LM163 X2 H X7 H X2 H H H D H LM164 X2 H X7 H X2 H H H D D LM165 Y4 H X7 H Y4 H H H D D LM166 Y5 H X7 H Y5 H H H D D LM167 Y6 H X7 H Y6 H H H D D LM168 Y7 H X7 H Y7 H H H D D LM169 Y8 H X7 H Y8 H H H D D LM170 Y9 H X7 H Y9 H H H D D LM171 Y10 H X7 H Y10 H H H D D LM172 Y10 D X7 D Y10 H H H D D LM173 Y10 D X7 D Y10 D H H D D LM174 Y10 D X7 D Y10 D D H D D LM175 Y10 D X7 D Y10 D D D D D LM176 Y10 D X8 D Y10 D D D D D LM177 Y10 D Y16 D Y10 D D D D D LM178 Y10 D Y17 D Y10 D D D D D LM179 Y10 D Y18 D Y10 D D D D D LM180 Y10 D Y15 D Y10 D D D D D LM181 Y10 D Y15 D Y10 H X1 H D D LM182 Y10 D Y15 D Y10 D Y3 D D D LM183 Y10 D Y16 D Y10 D Y3 D D D LM184 Y10 D Y17 D Y10 D Y3 D D D LM185 Y10 D Y18 D Y10 D Y3 D D D LM186 Y10 D Y15 D Y10 H X4 H D D LM187 Y10 D Y15 D Y10 D Y12 D D D LM188 Y10 D Y16 D Y10 D Y12 D D D LM189 Y10 D Y17 D Y10 D Y12 D D D LM190 Y10 D Y18 D Y10 D Y12 D D D LM191 X1 X7 H H X1 H H H H D LM192 X1 X7 H H X1 H H H D H LM193 X1 X7 H H X1 H H H D D LM194 Y1 X7 H H Y1 H H H D D LM195 Y2 X7 H H Y2 H H H D D LM196 Y3 X7 H H Y3 H H H D D LM197 Y3 X7 D D Y3 H H H D D LM198 Y3 X7 D D Y3 D H H D D LM199 Y3 X7 D D Y3 D D H D D LM200 Y3 X7 D D Y3 D D D D D LM201 Y3 Y15 D D Y3 D D D D D LM202 Y3 Y16 D D Y3 D D D D D LM203 Y3 Y17 D D Y3 D D D D D LM204 Y3 Y18 D D Y3 D D D D D LM205 Y3 Y15 D D Y3 H X1 H D D LM206 Y3 Y15 D D Y3 D Y3 D D D LM207 Y3 Y16 D D Y3 D Y3 D D D LM208 Y3 Y17 D D Y3 D Y3 D D D LM209 Y3 Y18 D D Y3 D Y3 D D D LM210 Y3 Y15 D D Y3 H X4 H D D LM211 Y3 Y15 D D Y3 D Y12 D D D LM212 Y3 Y16 D D Y3 D Y12 D D D LM213 Y3 Y17 D D Y3 D Y12 D D D LM214 Y3 Y18 D D Y3 D Y12 D D D LM215 X2 X7 H H X2 H H H H D LM216 X2 X7 H H X2 H H H D H LM217 X2 X7 H H X2 H H H D D LM218 Y4 X7 H H Y4 H H H D D LM219 Y5 X7 H H Y5 H H H D D LM220 Y6 X7 H H Y6 H H H D D LM221 Y7 X7 H H Y7 H H H D D LM222 Y8 X7 H H Y8 H H H D D LM223 Y9 X7 H H Y9 H H H D D LM224 Y10 X7 H H Y10 H H H D D LM225 Y10 X7 D D Y10 H H H D D LM226 Y10 X7 D D Y10 D H H D D LM227 Y10 X7 D D Y10 D D H D D LM228 Y10 X7 D D Y10 D D D D D LM229 Y10 X8 D D Y10 D D D D D LM230 Y10 Y16 D D Y10 D D D D D LM231 Y10 Y17 D D Y10 D D D D D LM232 Y10 Y18 D D Y10 D D D D D LM233 Y10 Y15 D D Y10 D D D D D LM234 Y10 Y15 D D Y10 H X1 H D D LM235 Y10 Y15 D D Y10 D Y3 D D D LM236 Y10 Y16 D D Y10 D Y3 D D D LM237 Y10 Y17 D D Y10 D Y3 D D D LM238 Y10 Y18 D D Y10 D Y3 D D D LM239 Y10 Y15 D D Y10 H X4 H D D LM240 Y10 Y15 D D Y10 D Y12 D D D LM241 Y10 Y16 D D Y10 D Y12 D D D LM242 Y10 Y17 D D Y10 D Y12 D D D LM243 Y10 Y18 D D Y10 D Y12 D D D

TABLE-US-00006 TABLE 6 Formula 1-2 Ligand R.sub.11 X.sub.11 R.sub.101 R.sub.102 R.sub.103 R.sub.104 R.sub.14 R.sub.15 R.sub.16 R.sub.17 R.sub.18 R.sub.19 R.sub.20 LFM1 Y10 N-Ph D D D D D Y10 D D D D D LFM2 Y10 S D D D D D Y10 D D D D D LFM3 Y10 O D D D D D Y10 D D D D D LFM4 Y3 O D D D D D Y3 D D D D D LFM5 Y10 O D D D D D Y10 D D D D D LFM6 Y10 O D D D D D Y10 D Y3 D D D LFM7 Y10 O D D D D D Y10 D Y12 D D D

TABLE-US-00007 TABLE 7 Formula 1-3 Ligand R.sub.11 X.sub.11 R.sub.101 R.sub.102 R.sub.103 R.sub.104 R.sub.14 R.sub.15 R.sub.16 R.sub.17 R.sub.18 R.sub.19 R.sub.20 LFP1 Y10 N-Ph D D D D D Y10 D D D D D LFP2 Y10 S D D D D D Y10 D D D D D LFP3 Y10 O D D D D D Y10 D D D D D LFP4 Y3 O D D D D D Y3 D D D D D LFP5 Y10 O D D D D D Y10 D D D D D LFP6 Y10 O D D D D D Y10 D Y3 D D D LFP7 Y10 O D D D D D Y10 D Y12 D D D

[0398] In Tables 5 to 7, X1 to X10 and Y1 to Y18 are the same as described below, and Ph represents a phenyl group:

##STR01868## ##STR01869## ##STR01870## ##STR01871##

##STR01872## ##STR01873##

##STR01874## ##STR01875## ##STR01876## ##STR01877## ##STR01878## ##STR01879## ##STR01880## ##STR01881## ##STR01882## ##STR01883## ##STR01884## ##STR01885## ##STR01886## ##STR01887## ##STR01888## ##STR01889## ##STR01890## ##STR01891## ##STR01892## ##STR01893## ##STR01894## ##STR01895## ##STR01896## ##STR01897## ##STR01898## ##STR01899## ##STR01900## ##STR01901## ##STR01902## ##STR01903## ##STR01904## ##STR01905## ##STR01906## ##STR01907## ##STR01908## ##STR01909## ##STR01910## ##STR01911## ##STR01912## ##STR01913## ##STR01914## ##STR01915## ##STR01916## ##STR01917## ##STR01918## ##STR01919## ##STR01920## ##STR01921## ##STR01922## ##STR01923## ##STR01924## ##STR01925## ##STR01926## ##STR01927## ##STR01928## ##STR01929## ##STR01930## ##STR01931## ##STR01932## ##STR01933## ##STR01934## ##STR01935## ##STR01936## ##STR01937## ##STR01938## ##STR01939## ##STR01940## ##STR01941## ##STR01942## ##STR01943## ##STR01944## ##STR01945## ##STR01946## ##STR01947## ##STR01948## ##STR01949## ##STR01950##

##STR01951## ##STR01952## ##STR01953## ##STR01954## ##STR01955## ##STR01956## ##STR01957## ##STR01958## ##STR01959## ##STR01960## ##STR01961## ##STR01962## ##STR01963## ##STR01964## ##STR01965## ##STR01966## ##STR01967## ##STR01968## ##STR01969## ##STR01970## ##STR01971## ##STR01972## ##STR01973## ##STR01974##

##STR01975## ##STR01976## ##STR01977## ##STR01978## ##STR01979## ##STR01980## ##STR01981## ##STR01982## ##STR01983## ##STR01984## ##STR01985## ##STR01986## ##STR01987## ##STR01988## ##STR01989## ##STR01990## ##STR01991## ##STR01992## ##STR01993## ##STR01994## ##STR01995## ##STR01996## ##STR01997## ##STR01998## ##STR01999## ##STR02000## ##STR02001## ##STR02002## ##STR02003## ##STR02004## ##STR02005## ##STR02006##

##STR02007## ##STR02008## ##STR02009## ##STR02010## ##STR02011## ##STR02012## ##STR02013## ##STR02014## ##STR02015## ##STR02016## ##STR02017## ##STR02018## ##STR02019## ##STR02020## ##STR02021## ##STR02022## ##STR02023## ##STR02024## ##STR02025## ##STR02026## ##STR02027## ##STR02028## ##STR02029## ##STR02030## ##STR02031## ##STR02032## ##STR02033## ##STR02034## ##STR02035## ##STR02036## ##STR02037## ##STR02038## ##STR02039## ##STR02040## ##STR02041## ##STR02042## ##STR02043## ##STR02044## ##STR02045## ##STR02046## ##STR02047## ##STR02048## ##STR02049## ##STR02050## ##STR02051## ##STR02052## ##STR02053## ##STR02054## ##STR02055## ##STR02056## ##STR02057## ##STR02058## ##STR02059## ##STR02060## ##STR02061## ##STR02062## ##STR02063## ##STR02064## ##STR02065## ##STR02066## ##STR02067## ##STR02068## ##STR02069## ##STR02070## ##STR02071## ##STR02072## ##STR02073## ##STR02074## ##STR02075## ##STR02076## ##STR02077## ##STR02078## ##STR02079## ##STR02080##

##STR02081## ##STR02082## ##STR02083## ##STR02084## ##STR02085## ##STR02086## ##STR02087## ##STR02088## ##STR02089## ##STR02090## ##STR02091## ##STR02092## ##STR02093## ##STR02094## ##STR02095## ##STR02096## ##STR02097## ##STR02098## ##STR02099## ##STR02100## ##STR02101## ##STR02102## ##STR02103## ##STR02104## ##STR02105## ##STR02106## ##STR02107## ##STR02108## ##STR02109## ##STR02110## ##STR02111## ##STR02112## ##STR02113## ##STR02114## ##STR02115## ##STR02116## ##STR02117## ##STR02118## ##STR02119## ##STR02120## ##STR02121## ##STR02122## ##STR02123## ##STR02124## ##STR02125## ##STR02126## ##STR02127## ##STR02128## ##STR02129## ##STR02130## ##STR02131## ##STR02132## ##STR02133## ##STR02134## ##STR02135## ##STR02136## ##STR02137## ##STR02138## ##STR02139## ##STR02140## ##STR02141##

##STR02142## ##STR02143## ##STR02144## ##STR02145## ##STR02146## ##STR02147## ##STR02148## ##STR02149## ##STR02150## ##STR02151## ##STR02152## ##STR02153## ##STR02154## ##STR02155## ##STR02156## ##STR02157## ##STR02158## ##STR02159## ##STR02160## ##STR02161## ##STR02162## ##STR02163## ##STR02164## ##STR02165## ##STR02166## ##STR02167## ##STR02168## ##STR02169## ##STR02170## ##STR02171## ##STR02172## ##STR02173## ##STR02174## ##STR02175## ##STR02176## ##STR02177## ##STR02178## ##STR02179## ##STR02180## ##STR02181## ##STR02182## ##STR02183## ##STR02184## ##STR02185## ##STR02186## ##STR02187## ##STR02188## ##STR02189## ##STR02190##

[0399] In one or more embodiments, the sensitizer may be represented by Formula 101 or 102, and in this regard, the sensitizer may be referred to as a delayed fluorescence sensitizer:

##STR02191##

[0400] In Formulae 101 and 102,

[0401] A.sub.21 may be an acceptor group,

[0402] D.sub.21 may be a donor group,

[0403] m21 may be 1, 2, or 3, and n21 may be 1, 2, or 3,

[0404] the sum of n21 and m21 in Formula 101 may be 6 or less, and the sum of n21 and m21 in Formula 102 may be 5 or less,

[0405] R.sub.21 may be hydrogen, deuterium, —F, —Cl, —Br, —I, SF.sub.5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C.sub.1-C.sub.60 alkyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkenyl group, a substituted or unsubstituted C.sub.2-C.sub.60 alkynyl group, a substituted or unsubstituted C.sub.1-C.sub.60 alkoxy group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.7-C.sub.60 alkylaryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 alkylheteroaryl group, a substituted or unsubstituted C.sub.2-C.sub.60 heteroaryl alkyl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryloxy group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroarylthio group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —Ge(Q.sub.1)(Q.sub.2)(Q.sub.3), —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —B(Q.sub.1)(Q.sub.2), —N(Q.sub.1)(Q.sub.2), —P(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), —P(═O)(Q.sub.1)(Q.sub.2), or —P(═S)(Q.sub.1)(Q.sub.2), wherein a plurality of R.sub.21 may optionally be linked together to form a substituted or unsubstituted C.sub.5-C.sub.30 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.30 heterocyclic group, and

[0406] Q.sub.1 to Q.sub.3 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.7-C.sub.60 alkylaryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a C.sub.2-C.sub.60 alkyl heteroaryl group, a C.sub.1-C.sub.60 heteroaryloxy group, a C.sub.1-C.sub.60 heteroarylthio group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a C.sub.1-C.sub.60 alkyl group that is substituted with at least one deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof, or a C.sub.6-C.sub.60 aryl group that is substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.6-C.sub.60 aryl group, or a combination thereof.

[0407] For example, in Formulae 101 and 102, A.sub.21 may be a substituted or unsubstituted π electron-depleted nitrogen-free cyclic group.

[0408] In an embodiment, the π electron-depleted nitrogen-free cyclic group may be: a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentacene group, a rubicene group, a corogen group, an ovalene group, a pyrrole group, an isoindole group, an indole group, a furan group, a thiophene group, a benzofuran group, a benzothiophene group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a triindolobenzene group; or a condensed cyclic group of two or more π electron-depleted nitrogen-free cyclic groups, but embodiments of the present disclosure are not limited thereto.

[0409] In an embodiment, in Formulae 101 and 102, D.sub.21 may be:

[0410] —F, a cyano group, or a π electron-depleted nitrogen-containing cyclic group;

[0411] a C.sub.1-C.sub.60 alkyl group, a π electron-depleted nitrogen-containing cyclic group, or a π electron-depleted nitrogen-free cyclic group, each substituted with at least one —F, a cyano group, or a combination thereof; or

[0412] a π-electron depleted nitrogen-containing cyclic group substituted with at least one deuterium, a C.sub.1-C.sub.60 alkyl group, a π electron depleted nitrogen-containing cyclic group, a π electron-depleted nitrogen-free cyclic group, or a combination thereof.

[0413] In detail, the π electron-depleted nitrogen-free cyclic group may be the same as described herein.

[0414] The term “π electron-depleted nitrogen-containing cyclic group” as used herein refers to a cyclic group having at least one *—N═*′ moiety, and for example, may be: an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, or a benzimidazolobenzimidazole group; or a condensed cyclic group in which two or more π electron-efficient nitrogen-containing cyclic groups are condensed with each other.

[0415] In one or more embodiments, the sensitizer may be compounds of Groups XI to XV, but embodiments of the present disclosure are not limited thereto:

##STR02192## ##STR02193## ##STR02194## ##STR02195## ##STR02196## ##STR02197## ##STR02198## ##STR02199## ##STR02200## ##STR02201## ##STR02202## ##STR02203## ##STR02204## ##STR02205## ##STR02206## ##STR02207## ##STR02208## ##STR02209## ##STR02210## ##STR02211## ##STR02212## ##STR02213## ##STR02214## ##STR02215## ##STR02216## ##STR02217## ##STR02218## ##STR02219## ##STR02220## ##STR02221## ##STR02222## ##STR02223## ##STR02224##

##STR02225## ##STR02226## ##STR02227## ##STR02228## ##STR02229## ##STR02230## ##STR02231## ##STR02232## ##STR02233## ##STR02234## ##STR02235## ##STR02236## ##STR02237## ##STR02238## ##STR02239##

##STR02240## ##STR02241## ##STR02242## ##STR02243## ##STR02244## ##STR02245## ##STR02246## ##STR02247## ##STR02248## ##STR02249## ##STR02250## ##STR02251## ##STR02252## ##STR02253## ##STR02254## ##STR02255## ##STR02256## ##STR02257## ##STR02258## ##STR02259## ##STR02260## ##STR02261## ##STR02262## ##STR02263## ##STR02264## ##STR02265## ##STR02266## ##STR02267## ##STR02268## ##STR02269## ##STR02270## ##STR02271## ##STR02272## ##STR02273## ##STR02274## ##STR02275## ##STR02276## ##STR02277## ##STR02278## ##STR02279## ##STR02280## ##STR02281## ##STR02282## ##STR02283## ##STR02284## ##STR02285## ##STR02286## ##STR02287## ##STR02288## ##STR02289## ##STR02290## ##STR02291## ##STR02292## ##STR02293## ##STR02294## ##STR02295## ##STR02296## ##STR02297##

##STR02298## ##STR02299## ##STR02300## ##STR02301## ##STR02302## ##STR02303## ##STR02304## ##STR02305## ##STR02306## ##STR02307## ##STR02308## ##STR02309## ##STR02310## ##STR02311## ##STR02312## ##STR02313## ##STR02314## ##STR02315## ##STR02316## ##STR02317## ##STR02318## ##STR02319## ##STR02320## ##STR02321## ##STR02322## ##STR02323## ##STR02324## ##STR02325## ##STR02326## ##STR02327## ##STR02328## ##STR02329## ##STR02330## ##STR02331## ##STR02332## ##STR02333## ##STR02334## ##STR02335## ##STR02336## ##STR02337## ##STR02338## ##STR02339## ##STR02340## ##STR02341##

##STR02342## ##STR02343## ##STR02344## ##STR02345## ##STR02346## ##STR02347## ##STR02348## ##STR02349## ##STR02350## ##STR02351## ##STR02352## ##STR02353## ##STR02354## ##STR02355## ##STR02356## ##STR02357## ##STR02358## ##STR02359## ##STR02360## ##STR02361## ##STR02362## ##STR02363## ##STR02364## ##STR02365## ##STR02366## ##STR02367## ##STR02368## ##STR02369## ##STR02370## ##STR02371##

##STR02372## ##STR02373## ##STR02374## ##STR02375## ##STR02376## ##STR02377## ##STR02378## ##STR02379## ##STR02380## ##STR02381## ##STR02382## ##STR02383## ##STR02384## ##STR02385## ##STR02386## ##STR02387## ##STR02388## ##STR02389## ##STR02390## ##STR02391## ##STR02392## ##STR02393## ##STR02394## ##STR02395## ##STR02396## ##STR02397## ##STR02398## ##STR02399## ##STR02400## ##STR02401## ##STR02402## ##STR02403## ##STR02404## ##STR02405## ##STR02406## ##STR02407## ##STR02408## ##STR02409## ##STR02410## ##STR02411## ##STR02412## ##STR02413## ##STR02414## ##STR02415## ##STR02416## ##STR02417## ##STR02418## ##STR02419## ##STR02420## ##STR02421## ##STR02422## ##STR02423## ##STR02424## ##STR02425## ##STR02426## ##STR02427## ##STR02428## ##STR02429## ##STR02430## ##STR02431## ##STR02432## ##STR02433## ##STR02434## ##STR02435## ##STR02436## ##STR02437## ##STR02438## ##STR02439##

##STR02440## ##STR02441## ##STR02442## ##STR02443## ##STR02444## ##STR02445## ##STR02446## ##STR02447## ##STR02448## ##STR02449## ##STR02450## ##STR02451## ##STR02452## ##STR02453## ##STR02454## ##STR02455## ##STR02456## ##STR02457## ##STR02458## ##STR02459## ##STR02460## ##STR02461## ##STR02462## ##STR02463## ##STR02464## ##STR02465## ##STR02466## ##STR02467## ##STR02468## ##STR02469## ##STR02470## ##STR02471## ##STR02472## ##STR02473## ##STR02474## ##STR02475## ##STR02476## ##STR02477## ##STR02478## ##STR02479## ##STR02480## ##STR02481## ##STR02482## ##STR02483## ##STR02484## ##STR02485##

##STR02486## ##STR02487## ##STR02488## ##STR02489## ##STR02490## ##STR02491## ##STR02492## ##STR02493## ##STR02494## ##STR02495## ##STR02496## ##STR02497## ##STR02498## ##STR02499## ##STR02500## ##STR02501## ##STR02502## ##STR02503## ##STR02504## ##STR02505## ##STR02506## ##STR02507## ##STR02508## ##STR02509## ##STR02510## ##STR02511## ##STR02512## ##STR02513## ##STR02514## ##STR02515## ##STR02516## ##STR02517## ##STR02518## ##STR02519## ##STR02520## ##STR02521## ##STR02522## ##STR02523## ##STR02524## ##STR02525## ##STR02526## ##STR02527## ##STR02528## ##STR02529## ##STR02530## ##STR02531## ##STR02532## ##STR02533## ##STR02534## ##STR02535## ##STR02536## ##STR02537## ##STR02538## ##STR02539## ##STR02540## ##STR02541## ##STR02542## ##STR02543## ##STR02544## ##STR02545## ##STR02546## ##STR02547## ##STR02548## ##STR02549## ##STR02550## ##STR02551## ##STR02552## ##STR02553## ##STR02554## ##STR02555## ##STR02556## ##STR02557## ##STR02558## ##STR02559## ##STR02560## ##STR02561## ##STR02562## ##STR02563## ##STR02564## ##STR02565## ##STR02566##

##STR02567## ##STR02568## ##STR02569## ##STR02570## ##STR02571## ##STR02572## ##STR02573## ##STR02574## ##STR02575## ##STR02576## ##STR02577## ##STR02578## ##STR02579## ##STR02580## ##STR02581## ##STR02582## ##STR02583## ##STR02584## ##STR02585## ##STR02586## ##STR02587## ##STR02588## ##STR02589## ##STR02590## ##STR02591## ##STR02592## ##STR02593## ##STR02594## ##STR02595## ##STR02596## ##STR02597## ##STR02598## ##STR02599## ##STR02600## ##STR02601## ##STR02602## ##STR02603## ##STR02604## ##STR02605## ##STR02606## ##STR02607## ##STR02608## ##STR02609## ##STR02610## ##STR02611## ##STR02612## ##STR02613## ##STR02614## ##STR02615## ##STR02616## ##STR02617## ##STR02618## ##STR02619## ##STR02620## ##STR02621## ##STR02622## ##STR02623## ##STR02624## ##STR02625## ##STR02626## ##STR02627## ##STR02628## ##STR02629## ##STR02630## ##STR02631## ##STR02632## ##STR02633## ##STR02634##

##STR02635## ##STR02636## ##STR02637## ##STR02638## ##STR02639## ##STR02640## ##STR02641## ##STR02642## ##STR02643## ##STR02644## ##STR02645## ##STR02646## ##STR02647## ##STR02648## ##STR02649## ##STR02650## ##STR02651## ##STR02652## ##STR02653## ##STR02654## ##STR02655## ##STR02656## ##STR02657## ##STR02658## ##STR02659## ##STR02660## ##STR02661## ##STR02662## ##STR02663## ##STR02664## ##STR02665## ##STR02666## ##STR02667## ##STR02668## ##STR02669## ##STR02670## ##STR02671## ##STR02672## ##STR02673## ##STR02674## ##STR02675## ##STR02676## ##STR02677## ##STR02678## ##STR02679## ##STR02680## ##STR02681## ##STR02682## ##STR02683## ##STR02684## ##STR02685## ##STR02686## ##STR02687## ##STR02688## ##STR02689## ##STR02690## ##STR02691## ##STR02692## ##STR02693## ##STR02694## ##STR02695## ##STR02696## ##STR02697## ##STR02698## ##STR02699## ##STR02700## ##STR02701## ##STR02702## ##STR02703## ##STR02704##

##STR02705## ##STR02706## ##STR02707## ##STR02708## ##STR02709## ##STR02710## ##STR02711## ##STR02712## ##STR02713## ##STR02714## ##STR02715## ##STR02716## ##STR02717## ##STR02718## ##STR02719## ##STR02720## ##STR02721## ##STR02722## ##STR02723## ##STR02724## ##STR02725## ##STR02726## ##STR02727## ##STR02728## ##STR02729## ##STR02730## ##STR02731## ##STR02732## ##STR02733## ##STR02734## ##STR02735## ##STR02736## ##STR02737## ##STR02738## ##STR02739## ##STR02740## ##STR02741## ##STR02742## ##STR02743## ##STR02744## ##STR02745## ##STR02746## ##STR02747## ##STR02748## ##STR02749## ##STR02750## ##STR02751## ##STR02752## ##STR02753## ##STR02754## ##STR02755## ##STR02756## ##STR02757## ##STR02758## ##STR02759## ##STR02760## ##STR02761## ##STR02762## ##STR02763## ##STR02764## ##STR02765## ##STR02766## ##STR02767## ##STR02768## ##STR02769## ##STR02770## ##STR02771## ##STR02772## ##STR02773## ##STR02774## ##STR02775## ##STR02776## ##STR02777## ##STR02778## ##STR02779## ##STR02780## ##STR02781## ##STR02782##

##STR02783## ##STR02784## ##STR02785## ##STR02786## ##STR02787## ##STR02788## ##STR02789## ##STR02790## ##STR02791## ##STR02792## ##STR02793## ##STR02794## ##STR02795## ##STR02796## ##STR02797## ##STR02798## ##STR02799## ##STR02800## ##STR02801## ##STR02802## ##STR02803## ##STR02804## ##STR02805## ##STR02806## ##STR02807## ##STR02808## ##STR02809## ##STR02810## ##STR02811## ##STR02812## ##STR02813## ##STR02814## ##STR02815## ##STR02816## ##STR02817## ##STR02818## ##STR02819## ##STR02820## ##STR02821## ##STR02822## ##STR02823## ##STR02824## ##STR02825## ##STR02826## ##STR02827## ##STR02828## ##STR02829## ##STR02830## ##STR02831## ##STR02832## ##STR02833## ##STR02834## ##STR02835## ##STR02836## ##STR02837## ##STR02838## ##STR02839## ##STR02840## ##STR02841## ##STR02842## ##STR02843## ##STR02844## ##STR02845## ##STR02846## ##STR02847## ##STR02848## ##STR02849## ##STR02850## ##STR02851##

##STR02852## ##STR02853## ##STR02854## ##STR02855## ##STR02856## ##STR02857## ##STR02858## ##STR02859## ##STR02860## ##STR02861## ##STR02862## ##STR02863## ##STR02864## ##STR02865## ##STR02866## ##STR02867## ##STR02868## ##STR02869## ##STR02870## ##STR02871##

##STR02872## ##STR02873## ##STR02874## ##STR02875## ##STR02876## ##STR02877## ##STR02878## ##STR02879## ##STR02880## ##STR02881## ##STR02882## ##STR02883## ##STR02884## ##STR02885## ##STR02886## ##STR02887##

[Hole Transport Region 12]

[0416] In the organic light-emitting device 10, the hole transporting region 12 may be arranged between the first electrode 11 and the emission layer 15.

[0417] The hole transport region 12 may have a single-layered structure or a multi-layered structure.

[0418] For example, the hole transport region 12 may have a hole injection layer structure, a hole transport layer structure, a hole injection layer/hole transport layer structure, a hole injection layer/first hole transport layer/second hole transport layer structure, a hole transport layer/interlayer structure, a hole injection layer/hole transport layer/interlayer structure, a hole transport layer/electron blocking layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, but embodiments of the present disclosure are not limited thereto.

[0419] The hole transport region 12 may include any compound having hole-transporting properties.

[0420] For example, the hole transport region 12 may include an amine-based compound.

[0421] In an embodiment, the hole transport region 12 may include at least one compound represented by Formulae 201 to 205, but embodiments of the present disclosure are not limited thereto:

##STR02888##

[0422] In Formulae 201 to 205,

[0423] L.sub.201 to L.sub.209 may each independently *-be O—*′, *—S—*′, a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group, or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

[0424] xa1 to xa9 may each independently be an integer from 0 to 5, and

[0425] R.sub.201 to R.sub.206 may each independently be a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.6 heteroaryl group, a substituted or unsubstituted monovalent aromatic condensed polycyclic group, a substituted or unsubstituted monovalent aromatic condensed heteropolycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, wherein neighboring two groups of R.sub.201 to R.sub.206 may optionally be linked to each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

[0426] For example,

[0427] L.sub.201 to L.sub.209 may each independently be a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, a heptalene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentacene group, a rubicene group, a corogen group, an ovalene group, a pyrrole group, an isoindole group, an indole group, a furan group, a thiophene group, a benzofuran group, a benzothiophene group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a dibenzothiophene sulfone group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, or a triindolobenzene group, each unsubstituted or substituted with at least one deuterium, a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triphenylenyl group, a biphenyl group, a terphenyl group, a tetraphenyl group, —Si(Q.sub.11)(Q.sub.12)(Q.sub.13), or any combination thereof,

[0428] xa1 to xa9 may each independently be 0, 1, or 2,

[0429] R.sub.201 to R.sub.206 may each independently be a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an indeno carbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, or a benzothienocarbazolyl group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with —F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), or any combination thereof, and

[0430] Q.sub.11 to Q.sub.13 and Q.sub.31 to Q.sub.33 may each independently be a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.

[0431] In one or more embodiments, the hole transport region 12 may include a carbazole-containing amine-based compound.

[0432] In one or more embodiments, the hole transport region 12 may include a carbazole-containing amine-based compound and a carbazole-free amine-based compound.

[0433] The carbazole-containing amine-based compound may be, for example, a compound represented by Formula 201 including a carbazole group and further including at least one of a dibenzofuran group, a dibenzothiophene group, a fluorene group, a spiro-bifluorene group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, or any combination thereof.

[0434] The carbazole-free amine-based compound may be, for example, a compound represented by Formula 201 which does not include a carbazole group and which includes at least one of a dibenzofuran group, a dibenzothiophene group, a fluorene group, a spiro-bifluorene group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, or any combination thereof.

[0435] In one or more embodiments, the hole transport region 12 may include at least one compound represented by Formulae 201 or 202.

[0436] In an embodiment, the hole transport region 12 may include at least one compound represented by Formulae 201-1, 202-1, or 201-2, but embodiments of the present disclosure are not limited thereto:

##STR02889##

[0437] In Formulae 201-1, 202-1, and 201-2, L.sub.201 to L.sub.203, L.sub.205, xa1 to xa3, xa5, R.sub.201 and R.sub.202 may respectively be the same as described herein, and R.sub.211 to R.sub.213 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C.sub.1-C.sub.10 alkyl group, a phenyl group substituted with —F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a triphenylenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, or a pyridinyl group.

[0438] For example, the hole transport region 12 may include at least one of Compounds HT1 to HT39, but embodiments of the present disclosure are not limited thereto:

##STR02890## ##STR02891## ##STR02892## ##STR02893## ##STR02894## ##STR02895## ##STR02896## ##STR02897##

[0439] In one or more embodiments, the hole transport region 12 may include at least one of 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC), tris(4-carbazoyl-9-ylphenyl)amine (TCTA), or any combination thereof.

[0440] In one or more embodiments, the hole transport region 12 of the organic light-emitting device 10 may further include a p-dopant. When the hole transport region 12 further includes a p-dopant, the hole transport region 12 may have a structure including a matrix (for example, at least one of compounds represented by Formulae 201 to 205) and a p-dopant included in the matrix. The p-dopant may be uniformly or non-uniformly doped in the hole transport region 12.

[0441] For example, a lowest unoccupied molecular orbital (LUMO) energy level of the p-dopant may be about −3.5 eV or less.

[0442] The p-dopant may include at least one a quinone derivative, a metal oxide, a cyano group-containing compound, or any combination thereof, but embodiments of the present disclosure are not limited thereto.

[0443] In an embodiment, the p-dopant may include at least one of:

[0444] a quinone derivative, such as tetracyanoquinodimethane (TCNQ),2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), and F6-TCNNQ;

[0445] a metal oxide, such as tungsten oxide or molybdenum oxide;

[0446] 1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (HAT-CN);

[0447] a compound represented by Formula 221, or any combination thereof, but embodiments of the present disclosure are not limited thereto:

##STR02898##

[0448] In Formula 221,

[0449] R.sub.221 to R.sub.223 may each independently be a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent aromatic condensed polycyclic group, a substituted or unsubstituted monovalent aromatic condensed heteropolycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, or a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, wherein at least one of R.sub.221 to R.sub.223 may have at least one of a cyano group, —F, —Cl, —Br, —I, a C.sub.1-C.sub.20 alkyl group substituted with —F, a C.sub.1-C.sub.20 alkyl group substituted with —Cl, a C.sub.1-C.sub.20 alkyl group substituted with —Br, a C.sub.1-C.sub.20 alkyl group substituted with —I, or any combination thereof.

[0450] The hole transport region 12 may have a thickness in a range of about 100 Å to about 10,000 Å, for example, about 400 Å to about 2,000 Å, and the emission layer 15 may have a thickness in a range of about 100 Å to about 3,000 Å, for example, about 300 Å to about 1,000 Å. When the thickness of each of the hole transport region 12 and the emission layer 15 is within these ranges, satisfactory hole transportation characteristics and/or luminescence characteristics may be obtained without a substantial increase in driving voltage.

[Electron Transport Region 17]

[0451] The electron transport region 17 is arranged between the emission layer 15 and the second electrode 19 of the organic light-emitting device 10.

[0452] The electron transport region 17 may have a single-layered structure or a multi-layered structure.

[0453] For example, the electron transport region 17 may have an electron transport layer structure, an electron transport layer/electron injection layer structure, a buffer layer/electron transport layer structure, hole blocking layer/electron transport layer structure, a buffer layer/electron transport layer/electron injection layer structure, or a hole blocking layer/electron transport layer/electron injection layer structure, but embodiments of the present disclosure are not limited thereto. The electron transport region 17 may further include an electron control layer.

[0454] The electron transport region 17 may include a known electron-transporting material.

[0455] The electron transport region 17 (for example, a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound containing at least one π electron-depleted nitrogen-containing cyclic group. The π electron-depleted nitrogen-containing cyclic group may be the same as described above.

[0456] In an embodiment, the electron transport region 17 may include a compound represented by Formula 601:

[Ar.sub.601].sub.xe11-[(L.sub.601).sub.xe1-R.sub.601].sub.xe21  Formula 601

[0457] wherein, in Formula 601,

[0458] Ar.sub.601 and L.sub.601 may each independently be a substituted or unsubstituted C.sub.5-C.sub.60 carbocyclic group or a substituted or unsubstituted C.sub.1-C.sub.60 heterocyclic group,

[0459] xe11 may be 1, 2, or 3,

[0460] xe1 may be an integer from 0 to 5,

[0461] R.sub.601 may be a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkyl group, a substituted or unsubstituted C.sub.3-C.sub.10 cycloalkenyl group, a substituted or unsubstituted C.sub.1-C.sub.10 heterocycloalkenyl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryl group, a substituted or unsubstituted C.sub.6-C.sub.60 aryloxy group, a substituted or unsubstituted C.sub.6-C.sub.60 arylthio group, a substituted or unsubstituted C.sub.1-C.sub.60 heteroaryl group, a substituted or unsubstituted monovalent aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent aromatic condensed heteropolycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q.sub.601)(Q.sub.602)(Q.sub.603), —C(═O)(Q.sub.601), —S(═O).sub.2(Q.sub.601), or —P(═O)(Q.sub.601)(Q.sub.602),

[0462] Q.sub.601 to Q.sub.603 may each independently be a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, and

[0463] xe21 may be an integer from 1 to 5.

[0464] In an embodiment, at least one of Ar.sub.601(s) in the number of xe11 and R.sub.601(s) in the number of xe21 may include the π electron-depleted nitrogen-containing cyclic group.

[0465] In an embodiment, Ar.sub.601 and L.sub.601 in Formula 601 may each independently be a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentaphene group, an indenoanthracene group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, or an azacarbazole group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof, and

[0466] Q.sub.31 to Q.sub.33 may each independently be a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.

[0467] When xe11 in Formula 601 is 2 or more, two or more of Ar.sub.601 may be linked together via a single bond.

[0468] In one or more embodiments, Ar.sub.601 in Formula 601 may be an anthracene group.

[0469] In one or more embodiments, the compound represented by Formula 601 may be represented by Formula 601-1:

##STR02899##

[0470] In Formula 601-1,

[0471] X.sub.614 may be N or C(R.sub.614), X.sub.615 may be N or C(R.sub.615), X.sub.616 may be N or C(R.sub.616), and at least one of X.sub.614 to X.sub.616 may be N,

[0472] L.sub.611 to L.sub.613 may each independently be the same as described in connection with L.sub.601,

[0473] xe611 to xe613 may each independently be the same as described in connection with xe1,

[0474] R.sub.611 to R.sub.613 may each independently be the same as described in connection with R.sub.601, and

[0475] R.sub.614 to R.sub.616 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.

[0476] In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.

[0477] In one or more embodiments, R.sub.601 and R.sub.611 to R.sub.613 in Formulae 601 and 601-1 may each independently be:

[0478] a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, or an azacarbazolyl group, each unsubstituted or substituted with at least one deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a thiophenyl group, a furanyl group, a carbazolyl group, an indolyl group, an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, or any combination thereof, and

[0479] —S(═O).sub.2(Q.sub.601) or —P(═O)(Q.sub.601)(Q.sub.602), and

[0480] Q.sub.601 and Q.sub.602 may respectively be the same as described above.

[0481] In an embodiment, the electron transport region 17 may include at least one compound of Compounds ET1 to ET36, but embodiments of the present disclosure are not limited thereto:

##STR02900## ##STR02901## ##STR02902## ##STR02903## ##STR02904## ##STR02905## ##STR02906##

[0482] In one or more embodiments, the electron transport region 17 may include at least one compound of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq.sub.3, BAlq, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), 2,2′,2″-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi), NTAZ, or any combination thereof:

##STR02907##

[0483] Thicknesses of the buffer layer, the hole blocking layer, and the electron control layer may each independently be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thicknesses of the buffer layer, the hole blocking layer, and the electron control layer are within these ranges, excellent hole blocking characteristics or excellent electron control characteristics may be obtained without a substantial increase in driving voltage.

[0484] A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within these ranges, satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.

[0485] The electron transport region 17 (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

[0486] The metal-containing material may include at least one of an alkali metal complex, an alkaline earth-metal complex, or a combination thereof. The alkali metal complex may include a metal ion of a Li ion, a Na ion, a K ion, a Rb ion, a Cs ion, or any combination thereof, and the alkaline earth-metal complex may include a metal ion of a Be ion, a Mg ion, a Ca ion, a Sr ion, a Ba ion, or any combination thereof. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may be a hydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, a hydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxy diphenylthiadiazole, a hydroxy phenylpyridine, a hydroxy phenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, a phenanthroline, or a cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

[0487] In an embodiment, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate (LiQ)) or ET-D2:

##STR02908##

[0488] The electron transport region 17 may include an electron injection layer that facilitates the injection of electrons from the second electrode 19. The electron injection layer may directly contact the second electrode 19.

[0489] The electron injection layer may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

[0490] The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof.

[0491] The alkali metal may be Li, Na, K, Rb, or Cs. In an embodiment, the alkali metal may be Li, Na, or Cs. In one or more embodiments, the alkali metal may be Li or Cs, but embodiments of the present disclosure are not limited thereto.

[0492] The alkaline earth metal may be Mg, Ca, Sr, or Ba.

[0493] The rare earth metal may be Sc, Y, Ce, Tb, Yb, or Gd.

[0494] The alkali metal compound, the alkaline earth-metal compound, and the rare earth metal compound may be an oxide or a halide (for example, fluorides, chlorides, bromides, or iodides) of the alkali metal, the alkaline earth-metal, or the rare earth metal.

[0495] The alkali metal compound may be an alkali metal oxide, such as Li.sub.2O, Cs.sub.2O, or K.sub.2O, or alkali metal halides, such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI. In an embodiment, the alkali metal compound may be LiF, Li.sub.2O, NaF, LiI, NaI, CsI, or KI, but embodiments of the present disclosure are not limited thereto.

[0496] The alkaline earth-metal compound may be an alkaline earth-metal oxide, such as BaO, SrO, CaO, Ba.sub.xSr.sub.1-xO (0<x<1), or Ba.sub.xCa.sub.1-xO (0<x<1). In an embodiment, the alkaline earth-metal compound may be BaO, SrO, or CaO, but embodiments of the present disclosure are not limited thereto.

[0497] The rare earth metal compound may be YbF.sub.3, ScF.sub.3, ScO.sub.3, Y.sub.2O.sub.3, Ce.sub.2O.sub.3, GdF.sub.3, or TbF.sub.3. In an embodiment, the rare earth metal compound may be YbF.sub.3, ScF.sub.3, TbF.sub.3, YbI.sub.3, ScI.sub.3, or TbI.sub.3, but embodiments of the present disclosure are not limited thereto.

[0498] The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an ion of an alkali metal, an alkaline earth-metal, or a rare earth metal as described above, and a ligand coordinated with a metal ion of the alkali metal complex, the alkaline earth-metal complex, or the rare earth metal complex may be hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline, hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxy phenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazole, hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine, phenanthroline, or cyclopentadiene, but embodiments of the present disclosure are not limited thereto.

[0499] The electron injection layer may comprise of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof, as described above. In one or more embodiments, the electron injection layer may further include an organic material. When the electron injection layer further includes an organic material, an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

[0500] A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within these ranges, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.

[Second Electrode 19]

[0501] The second electrode 19 is arranged on the organic layer 10 Å having such a structure. The second electrode 19 may be a cathode which is an electron injection electrode, and in this regard, a material for forming the second electrode 19 may be a metal, an alloy, an electrically conductive compound, or a combination thereof, which have a relatively low work function.

[0502] The second electrode 19 may include at least one lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ITO, IZO, or any combination thereof, but embodiments of the present disclosure are not limited thereto. The second electrode 19 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

[0503] The second electrode 19 may have a single-layered structure having a single layer or a multi-layered structure including two or more layers.

[0504] Hereinbefore, the organic light-emitting device has been described with reference to FIG. 1, but embodiments of the present disclosure are not limited thereto.

Description of FIG. 2

[0505] FIG. 2 is a schematic cross-sectional view of an organic light-emitting device 100 according to another exemplary embodiment.

[0506] The organic light-emitting device 100 of FIG. 2 includes a first electrode 110, a second electrode 190 facing the first electrode 110, and a first emitting unit 151 and a second emitting unit 152 between the first electrode 110 and the second electrode 190. A charge generation layer 141 is arranged between the first emitting unit 151 and the second emitting unit 152, and the charge generation layer 141 may include an n-type charge generation layer 141-N and a p-type charge generation layer 141-P. The charge generation layer 141 is a layer that generates a charge and supplies the charge to neighboring emitting units, and any known material may be used therefor.

[0507] The first emitting unit 151 may include a first emission layer 151-EM, and the second emitting unit 152 may include a second emission layer 152-EM. A maximum emission wavelength of light emitted from the first emitting unit 151 may be different from a maximum emission wavelength of light emitted from the second emitting unit 152. For example, the mixed light including the light emitted from the first emitting unit 151 and the light emitted from the second emitting unit 152 may be white light, but embodiments of the present disclosure are not limited thereto.

[0508] The hole transport region 120 is arranged between the first emitting unit 151 and the first electrode 110, and the second emitting unit 152 may include a first hole transport region 121 arranged on the side of the first electrode 110.

[0509] An electron transport region 170 is arranged between the second emitting unit 152 and the second electrode 190, and the first emitting unit 151 may include a first electron transport region 171 arranged between the charge generation layer 141 and the first emission layer 151-EM.

[0510] The first emission layer 151-EM may include the heterocyclic compound.

[0511] The second emission layer 152-EM may include the heterocyclic compound.

[0512] The first electrode 110 and the second electrode 190 illustrated in FIG. 2 may be the same as described in connection with the first electrode 11 and the second electrode 19 illustrated in FIG. 1.

[0513] The first emission layer 151-EM and the second emission layer 152-EM illustrated in FIG. 2 may each be the same as described in connection with the emission layer 15 illustrated in FIG. 1.

[0514] The hole transport region 120 and the first hole transport region 121 illustrated in FIG. 2 may each be the same as described in connection with the hole transport region 12 illustrated in FIG. 1.

[0515] The electron transport region 170 and the first electron transport region 171 illustrated in FIG. 2 may each be the same as described in connection with the electron transport region 17 illustrated in FIG. 1.

[0516] As described above, referring to FIG. 2, the organic light-emitting device in which each of the first emitting unit 151 and the second emitting unit 152 includes the emission layer including the host, the dopant, and the sensitizer, has been described. However, the organic light-emitting device may have various other forms. For example, one of the first emitting unit 151 and the second emitting unit 152 of the organic light-emitting device 100 of FIG. 2 may be replaced with any known emitting unit, or may include three or more emitting units.

[Description of FIG. 3]

[0517] FIG. 3 is a schematic cross-sectional view of an organic light-emitting device 200 according to another exemplary embodiment.

[0518] The organic light-emitting device 200 includes a first electrode 210, a second electrode 290 facing the first electrode 210, and a first emission layer 251 and a second emission layer 252 which are stacked between the first electrode 210 and the second electrode 290.

[0519] A maximum emission wavelength of light emitted from the first emission layer 251 may be different from a maximum emission wavelength of light emitted from the second emission layer 252. For example, the mixed light of the light emitted from the first emission layer 251 and the light emitted from the second emission layer 252 may be white light, but embodiments of the present disclosure are not limited thereto.

[0520] In an embodiment, a hole transport region 220 may be arranged between the first emission layer 251 and the first electrode 210, and an electron transport region 270 may be arranged between the second emission layer 252 and the second electrode 290.

[0521] The first emission layer 251 may include the heterocyclic compound.

[0522] The second emission layer 252 may include the heterocyclic compound.

[0523] The first electrode 210, the hole transport region 220, and the second electrode 290 illustrated in FIG. 3 may each be the same as described in connection with the first electrode 11, the hole transport region 12, and the second electrode 19 illustrated in FIG. 1.

[0524] The first emission layer 251 and the second emission layer 252 illustrated in FIG. 3 may each be the same as described in connection with the emission layer 15 illustrated in FIG. 1.

[0525] The electron transport region 270 illustrated in FIG. 3 may be the same as described in connection with the electron transport region 17 illustrated in FIG. 1.

[0526] As described above, referring to FIG. 3, the organic light-emitting device in which both the first emission layer 251 and the second emission layer 252 include the heterocyclic compound has been described. However, any one of the two emission layers 251 and 252 in the organic light-emitting device may be replaced with a known layer, the organic light-emitting device may include three or more emission layers, or the organic light-emitting device may further include an interlayer arranged between neighboring emission layers. As such, various modifications of the organic light-emitting device may be provided.

Electronic Apparatus

[0527] The organic light-emitting device may be included in various electronic apparatuses.

[0528] The electronic apparatus may further include a thin-film transistor in addition to the organic light-emitting device as described above. The thin-film transistor may include a source electrode, a drain electrode, and an activation layer, wherein any one of the source electrode and the drain electrode may be electrically connected to any one of the first electrode and the second electrode of the organic light-emitting device.

Explanation of Terms

[0529] The term “C.sub.1-C.sub.60 alkyl group” as used herein refers to a linear or branched saturated aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, and a hexyl group. The term “C.sub.1-C.sub.60 alkylene group” as used herein refers to a divalent group having the same structure as the C.sub.1-C.sub.60 alkyl group.

[0530] The term “C.sub.1-C.sub.60 alkoxy group” as used herein refers to a monovalent group represented by —OA.sub.101 (wherein A.sub.101 is the C.sub.1-C.sub.60 alkyl group), and examples thereof are a methoxy group, an ethoxy group, an isopropyloxy group, and the like.

[0531] The term “C.sub.2-C.sub.60 alkenyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon double bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group, and examples thereof are an ethenyl group, a propenyl group, a butenyl group, and the like. The term “C.sub.2-C.sub.60 alkenylene group” as used herein refers to a divalent group having the same structure as the C.sub.2-C.sub.60 alkenyl group.

[0532] The term “C.sub.2-C.sub.60 alkynyl group” as used herein refers to a hydrocarbon group formed by substituting at least one carbon-carbon triple bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group, and examples thereof are an ethynyl group, a propynyl group, and the like. The term “C.sub.2-C.sub.60 alkynylene group” as used herein refers to a divalent group having the same structure as the C.sub.2-C.sub.60 alkynyl group.

[0533] The term “C.sub.3-C.sub.10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and the like. The term “C.sub.3-C.sub.10 cycloalkylene group” as used herein refers to a divalent group having the same structure as the C.sub.3-C.sub.10 cycloalkyl group.

[0534] The term “C.sub.1-C.sub.10 heterocycloalkyl group” as used herein refers to a monovalent saturated monocyclic group having at least one heteroatom of N, O, P, Si, S, B, Se, Ge, Te or a combination thereof as a ring-forming atom and 1 to 10 carbon atoms, and examples thereof are a tetrahydrofuranyl group, a tetrahydrothiophenyl group, and the like. The term “C.sub.1-C.sub.10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C.sub.1-C.sub.10 heterocycloalkyl group.

[0535] The term “C.sub.3-C.sub.10 cycloalkenyl group” as used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and examples thereof are a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, and the like. The term “C.sub.3-C.sub.10 cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C.sub.3-C.sub.10 cycloalkenyl group.

[0536] The term “C.sub.1-C.sub.10 heterocycloalkenyl group” as used herein refers to a monovalent monocyclic group that has at least one heteroatom N, O, P, Si, S, B, Se, Ge, Te or a combination thereof as a ring-forming atom, 1 to 10 carbon atoms, and at least one carbon-carbon double bond in its ring. Examples of the C.sub.1-C.sub.10 heterocycloalkenyl group are a 2,3-dihydrofuranyl group, a 2,3-dihydrothiophenyl group, and the like. The term “C.sub.1-C.sub.10 heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C.sub.1-C.sub.10 heterocycloalkenyl group.

[0537] The term “C.sub.6-C.sub.60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C.sub.6-C.sub.60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C.sub.6-C.sub.60 aryl group are a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a chrysenyl group, and the like. When the C.sub.6-C.sub.60 aryl group and the C.sub.6-C.sub.60 arylene group each include two or more rings, the two or more rings may be fused to each other.

[0538] The term “C.sub.1-C.sub.60 heteroaryl group” as used herein refers to a monovalent group having a heterocarbocyclic aromatic system that has at least one heteroatom N, O, P, Si, and S as a ring-forming atom, and 1 to 60 carbon atoms. The term “C.sub.1-C.sub.60 heteroarylene group” as used herein refers to a divalent group having a carbocyclic aromatic system that has at least one heteroatom N, O, P, S, B, Se, Ge, Te, or a combination thereof as a ring-forming atom, and 1 to 60 carbon atoms. Examples of the C.sub.1-C.sub.60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, an isoquinolinyl group, and the like. When the C.sub.6-C.sub.60 heteroaryl group and the C.sub.6-C.sub.60 heteroarylene group each include two or more rings, the two or more rings may be fused to each other.

[0539] The term “C.sub.6-C.sub.60 aryloxy group” as used herein indicates —OA.sub.102 (wherein A.sub.102 is the C.sub.6-C.sub.60 aryl group), and the term “C.sub.6-C.sub.60 arylthio group” as used herein indicates —SA.sub.103 (wherein A.sub.103 is the C.sub.6-C.sub.60 aryl group).

[0540] The “(C.sub.1-C.sub.20 alkyl) ‘X’ group” refers to a ‘X’ group substituted with at least one C.sub.1-C.sub.20 alkyl group. For example, The “(C.sub.1-C.sub.20 alkyl)C.sub.3-C.sub.10 cycloalkyl group” as used herein refers to a C.sub.3-C.sub.10 cycloalkyl group substituted with at least one C.sub.1-C.sub.20 alkyl group, and the “(C.sub.1-C.sub.20 alkyl)phenyl group” as used herein refers to a phenyl group substituted with at least one C.sub.1-C.sub.20 alkyl group. Examples of the (C.sub.1 alkyl)phenyl group may include a toluyl group.

[0541] The term “monovalent aromatic condensed polycyclic group” as used herein refers to a monovalent group including two or more rings that are condensed with each other, including only carbon as a ring-forming atom (for example, 8 to 60 carbon atoms), and having aromaticity throughout its entire molecular structure. The term “divalent aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as the monovalent aromatic condensed polycyclic group described above.

[0542] The term “monovalent aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group having two or more rings condensed to each other, a heteroatom N, O, P, Si, S, B, Se, Ge, Te, or a combination thereof other than carbon atoms (for example, having 1 to 60 carbon atoms), as a ring-forming atom, and no aromaticity throughout its entire molecular structure. The term “divalent aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent aromatic condensed heteropolycyclic group described above.

[0543] The term “monovalent aromatic condensed polycyclic group” as used herein refers to a monovalent group including two or more rings that are condensed with each other, including only carbon as a ring-forming atom (for example, 8 to 60 carbon atoms), and having non-aromaticity throughout its entire molecular structure. Examples of the monovalent non-aromatic condensed polycyclic group are a fluorenyl group and the like. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group described above.

[0544] The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group having two or more rings condensed to each other, including a heteroatom N, O, P, Si, S, B, Se, Ge, Te, or a combination thereof other than carbon atoms (for example, 1 to 60 carbon atoms), as a ring-forming atom, and having no aromaticity throughout its entire molecular structure. Examples of the monovalent non-aromatic condensed heteropolycyclic group are a carbazolyl group and the like. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group described above.

[0545] The term “π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group” as used herein refers to a cyclic group having 1 to 60 carbon atoms and including at least one *—N═*′ (wherein * and *′ each indicate a binding site to a neighboring atom) as a ring-forming moiety, and examples thereof are a) first ring, b) a condensed cyclic group in which two or more first rings are condensed with each other, or c) a condensed cyclic group in which at least one first ring is condensed with at least one second ring.

[0546] The term “π electron-rich C.sub.3-C.sub.60 cyclic group” as used herein refers to a cyclic group having 3 to 60 carbon atoms and not including *—N═*′ (wherein * and *′ each indicate a binding site to a neighboring atom) as a ring-forming moiety, examples thereof are a) a second ring or b) a condensed cyclic group in which two or more second rings are condensed with each other.

[0547] The term “C.sub.5-C.sub.60 carbocyclic group” as used herein refers to a monocyclic group or a polycyclic group, each having 5 to 60 carbon atoms, and examples thereof are a) a third ring or b) a condensed cyclic group in which two or more third rings are condensed with each other.

[0548] The term “C.sub.1-C.sub.60 heterocyclic group” as used herein refers to a monocyclic group or a polycyclic group, each having 1 to 60 carbon atoms, and examples thereof are a) a fourth ring, b) a condensed cyclic group in which two or more fourth rings are condensed with each other, or c) a condensed cyclic group in which at least one third ring and at least one four ring are condensed with each other.

[0549] The term “first ring” as used herein may be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, or a thiadiazole group.

[0550] The term “second ring” as used herein may be a benzene group, a cyclopentadiene group, a pyrrole group, a furan group, a thiophene group, or a silole group.

[0551] The term “third ring” as used herein may be a cyclopentane group, a cyclopentadiene group, an indene group, an adamantane group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.1]heptane group (a norbornane group)), a bicyclo[2.2.2]octane group, a cyclohexane group, a cyclohexene group, or a benzene group.

[0552] The term “fourth ring” as used herein may be a furan group, a thiophene group, a pyrrole group, a silole group, an oxazole group, an isoxazole group, an oxadiazole group, an isoxadiazole group, an oxatriazole group, an isoxatriazole group, a thiazole group, an isothiazole group, a thiadiazole group, an isothiadiazole group, a thiatriazole group, an isothiatriazole group, a pyrazole group, an imidazole group, a triazole group, a tetrazole group, an azasilole group, a diazasilole group, a triazasilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, or a triazine group.

[0553] For example, the π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group may be an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyridazine group, a pyrimidine group, an indazole group, a purine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a phthalazine group, a naphthyridine group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a cinnoline group, a phenanthridine group, an acridine group, a phenanthroline group, a phenazine group, a benzimidazole group, an isobenzothiazole group, a benzoxazole group, a benzoisoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a thiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, an acridine group, or a pyridopyrazine group.

[0554] For example, the π electron-rich C.sub.3-C.sub.60 cyclic group may be a benzene group, a heptalene group, an indene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, a dibenzofluorene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a naphthacene group, a picene group, a perylene group, a pentacene group, a hexacene group, a pentaphene group, a rubicene group, a coronene group, an ovalene group, a pyrrole group, a furan group, a thiophene group, an isoindole group, an indole group, an indene group, a benzofuran group, a benzothiophene group, a benzosilole group, a naphthopyrrole group, a naphthofuran group, a naphthothiophene group, a naphthosilole group, a benzocarbazole group, a dibenzocarbazole group, a dibenzofuran group, a dibenzothiophene group, a carbazole group, a dibenzosilole group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a triindolobenzene group, a pyrrolophenanthrene group, a furanophenanthrene group, a thienophenanthrene group, a benzonaphthofuran group, a benzonaphthothiophene group, an (indolo)phenanthrene group, a (benzofuran)phenanthrene group, or a (benzothieno)phenanthrene group.

[0555] For example, the C.sub.5-C.sub.60 carbocyclic group may be a cyclopentane group, a cyclohexane group, a cyclohexene group, a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a 1,2,3,4-tetrahydronaphthalene group, a cyclopentadiene group, an indene group, a fluorene group, a 5,6,7,8-tetrahydroisoquinoline group, a 5,6,7,8-tetrahydroquinoline group, an adamantane group, a norbornane group, or a norbornene group.

[0556] For example, the C.sub.1-C.sub.60 heterocyclic group may be a thiophene group, a furan group, a pyrrole group, a cyclopentadiene group, a silole group, a borole group, phosphole group, a selenophene group, a germole group, a benzothiophene group, a benzofuran group, an indole group, an indene group, a benzosilole group, a benzoborole group, a benzophosphole group, a benzoselenophene group, a benzogermole group, a dibenzothiophene group, a dibenzofuran group, a carbazole group, a dibenzosilole group, a dibenzoborole group, a dibenzophosphole group, a dibenzoselenophene group, a dibenzogermole group, a dibenzothiophene 5-oxide group, a 9H-fluoren-9-one group, a dibenzothiophene 5,5-dioxide group, an azabenzothiophene group, an azabenzofuran group, an azaindole group, an azaindene group, an azabenzosilole group, an azabenzoborole group, an azabenzophosphole group, an azabenzoselenophene group, an azabenzogermole group, an azadibenzothiophene group, an azadibenzofuran group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzoborole group, an azadibenzophosphole group, an azadibenzoselenophene group, an azadibenzogermole group, an azadibenzothiophene 5-oxide group, an aza-9H-fluoren-9-one group, an azadibenzothiophene 5,5-dioxide group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, or a benzothiadiazole group.

[0557] The π electron-depleted nitrogen-containing C.sub.1-C.sub.60 cyclic group, the π electron-rich C.sub.3-C.sub.60 cyclic group, the C.sub.5-C.sub.60 cyclic group, and the C.sub.1-C.sub.60 heterocyclic group may each be a part of a condensed cycle or a monovalent, a divalent, a trivalent, a tetravalent, a pentavalent, or a hexavalent group, depending on the formula structure.

[0558] A substituent of at least one of the substituted C.sub.5-C.sub.30 carbocyclic group, the substituted C.sub.1-C.sub.30 heterocyclic group, the substituted C.sub.1-C.sub.60 alkyl group, the substituted C.sub.2-C.sub.60 alkenyl group, the substituted C.sub.2-C.sub.60 alkynyl group, the substituted C.sub.1-C.sub.60 alkoxy group, the substituted C.sub.3-C.sub.10 cycloalkyl group, the substituted C.sub.1-C.sub.10 heterocycloalkyl group, the substituted C.sub.3-C.sub.10 cycloalkenyl group, the substituted C.sub.1-C.sub.10 heterocycloalkenyl group, the substituted C.sub.6-C.sub.60 aryl group, the substituted C.sub.6-C.sub.60 aryloxy group, the substituted C.sub.6-C.sub.60 arylthio group, the substituted C.sub.1-C.sub.60 heteroaryl group, the substituted monovalent aromatic condensed polycyclic group, the substituted monovalent aromatic condensed heteropolycyclic group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be:

[0559] deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group;

[0560] a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each substituted with at least one of deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.11)(Q.sub.12), —Si(Q.sub.13)(Q.sub.14)(Q.sub.15), —B(Q.sub.16)(Q.sub.17), —P(═O)(Q.sub.18)(Q.sub.19), or any combination thereof;

[0561] a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group;

[0562] a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one of deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —N(Q.sub.21)(Q.sub.22), —Si(Q.sub.23)(Q.sub.24)(Q.sub.25), —B(Q.sub.26)(Q.sub.27), —P(═O)(Q.sub.28)(Q.sub.29), or any combination thereof; or

[0563] —N(Q.sub.31)(Q.sub.32), —Si(Q.sub.33)(Q.sub.34)(Q.sub.35), —B(Q.sub.36)(Q.sub.37), or —P(═O)(Q.sub.38)(Q.sub.39), and

[0564] Q.sub.1 to Q.sub.9, Q.sub.11 to Q.sub.19, Q.sub.21 to Q.sub.29, and Q.sub.31 to Q.sub.39 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryl group substituted with at least one a C.sub.1-C.sub.60 alkyl group, and a C.sub.6-C.sub.60 aryl group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent aromatic condensed polycyclic group, a monovalent aromatic condensed heteropolycyclic group, a monovalent non-aromatic condensed polycyclic group, or a monovalent non-aromatic condensed heteropolycyclic group.

[0565] As used herein, the number of carbons in each group that is substituted (e.g., C.sub.1-C.sub.60) excludes the number of carbons in the substituent. For example, a C.sub.1-C.sub.60 alkyl group can be substituted with a C.sub.1-C.sub.60 alkyl group. The total number of carbons included in the C.sub.1-C.sub.60 alkyl group substituted with the C.sub.1-C.sub.60 alkyl group is not limited to 60 carbons. In addition, more than one C.sub.1-C.sub.60alkyl substituent may be present on the C.sub.1-C.sub.60alkyl group. This definition is not limited to the C.sub.1-C.sub.60 alkyl group and applies to all substituted groups that recite a carbon range.

[0566] The term “room temperature” as used herein refers to a temperature of about 25° C.

[0567] The terms “a biphenyl group, a terphenyl group, and a tetraphenyl group” as used herein each refer to a monovalent group having two, three, and four phenyl groups linked via single bonds, respectively.

[0568] The terms “a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, and a cyano-containing tetraphenyl group” as used herein respectively refer to a phenyl group, a biphenyl group, a terphenyl group, and a tetraphenyl group, each of which is substituted with at least one cyano group. In “a cyano-containing phenyl group, a cyano-containing biphenyl group, a cyano-containing terphenyl group, and a cyano-containing tetraphenyl group”, a cyano group may be substituted to any position of the corresponding group, and the “cyano-containing phenyl group, the cyano-containing biphenyl group, the cyano-containing terphenyl group, and the cyano-containing tetraphenyl group” may further include substituents other than a cyano group. For example, a phenyl group substituted with a cyano group and a phenyl group substituted with a cyano group and a methyl group may all belong to “a cyano-containing phenyl group”.

[0569] Hereinafter, a compound and an organic light-emitting device according to embodiments are described in detail with reference to Synthesis Examples and Examples. However, the organic light-emitting device is not limited thereto. The wording “‘B’ was used instead of ‘A’” used in describing Synthesis Examples means that an amount of ‘A’ used was identical to an amount of ‘B’ used, in terms of a molar equivalent.

EXAMPLES

Synthesis Example 1: Synthesis of Compound 1

[0570] ##STR02909##

(1) Synthesis of Intermediate 1-1

[0571] In a 100 ml round-bottom flask, N-(5-(9H-carbazol-9-yl)-2,3-dichlorophenyl)-N-([1,1′-biphenyl]-4-yl)-[1,1′-biphenyl]-4-amine (3.3 g, 5.19 mmol), 6,12-diphenyl-9H-tribenzo[b,d,f]azepine (1.95 g, 4.93 mmol), Pd(dba).sub.2 (0.3 g, 0.52 mmol), SPhos (0.21 g, 0.52 mmol), and NaOtBu (0.75 g, 7.78 mmol) were mixed with toluene (31 ml), and the mixed solution was stirred by heating at 120° C. for 2 hours in a nitrogen atmosphere. The solvent of the reaction mixture obtained therefrom was removed using a rotary evaporator, and dichloromethane (200 ml) was added thereto to dissolve the reaction product. A washing process was performed thereon twice with water (200 ml), and water was removed using anhydrous MgSO.sub.4, and the solvent was removed using a rotary evaporator. The resulting product was then purified by silica gel column chromatography (dichloromethane/n-hexane), so as to obtain, as Intermediate 1-1, N-(5-(9H-carbazol-9-yl)-2-chloro-3-(6,12-diphenyl-9H-tribenzo[b,d,f]azepin-9-yl)phenyl)-N-([1,1′-biphenyl]-4-yl)-[1,1′-biphenyl]-4-amine (2.94 g). Intermediate 1-1 thus obtained was identified by LC-MS.

[0572] C.sub.72H.sub.48Cl.sub.1N.sub.3: 990.311

(2) Synthesis of Compound 1

[0573] In a 250 ml round-bottom flask, Intermediate 1-1 (4.67 g, 4.71 mmol) was mixed with t-butylbenzene (94 ml), and 1.6 M tert-BuLi pentane solution (7.4 ml, 11.77 mmol) was added thereto at −78° C. in a nitrogen atmosphere. The reaction temperature was raised to 60° C., and then, the mixed solution was stirred for 1 hour. The reaction solution was cooled to −40° C., and BBr.sub.3 (0.91 ml, 9.42 mmol) was added thereto and stirred at room temperature for 1 hour. Afterwards, the reaction solution was cooled to −40° C. again, and N,N-diisopropylethylamine (1.81 ml, 10.36 mmol) was added thereto and stirred by heating at 120° C. for 4 hours. After the reaction solution was cooled to room temperature, saturated aqueous solution of NaOAc and ethyl acetate (200 ml) were added thereto. A washing process was performed thereon using water (300 ml), and the organic layer was dried using anhydrous MgSO.sub.4. The solvent of the reaction product was removed using a rotary evaporator, and the resultant product was then purified by silica gel column chromatography (dichloromethane/n-hexane), so as to obtain Compound 1 (1.5 g). Compound 1 thus obtained was confirmed by LC-MS.

[0574] C.sub.72H.sub.46BN.sub.3: 964.333

Example 1-1

[0575] An ITO glass substrate was cut to a size of 50 mm×50 mm×0.5 mm, sonicated in acetone isopropyl alcohol and pure water, each for 15 minutes, and then, washed by exposure to ultraviolet (UV) light ozone for 30 minutes.

[0576] Subsequently, HAT-CN was deposited on the ITO electrode (anode) on the glass substrate to form a hole injection layer having a thickness of 100 Å, NPB was deposited on the hole injection layer to form a first hole transport layer having a thickness of 500 Å, TCTA was deposited on the first hole transport layer to form a second hole transport layer having a thickness of 50 Å, and mCP was deposited on the second hole transport layer to form an electron blocking layer having a thickness of 50 Å.

[0577] A first host (Compound H1), a second host (Compound H2), and a sensitizer (Compound 1) were co-deposited on the electron blocking layer to form an emission layer having a thickness of 400 Å. Here, the first host and the second host were mixed at a ratio of 60:40, and the amount of the emitter was adjusted to be 3 wt % based on the total weight of the first host, the second host, and the emitter.

[0578] DBFPO was deposited on the emission layer to form a hole blocking layer having a thickness of 100 Å, DBFPO and LiQ were co-deposited thereon at a weight ratio of 5:5 to form an electron transport layer having a thickness of 300 Å, LiQ was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, an then, Al was deposited on the electron injection layer to form a cathode having a thickness of 1,000 Å, thereby completing the manufacture of an organic light-emitting device.

##STR02910## ##STR02911##

Comparative Example 1-1

[0579] An organic light-emitting device was manufactured in the same manner as in Example 1-1, except that, in forming an emission layer, for use as a dopant, corresponding compounds shown in Table 3 were used.

Example 2-1

[0580] A glass substrate with an ITO electrode arranged thereon was cut to a size of 50 mm×50 mm×0.5 mm, sonicated in acetone isopropyl alcohol and pure water, each for 15 minutes, and then, washed by exposure to UV ozone for 30 minutes.

[0581] Subsequently, HAT-CN was deposited on the ITO electrode (anode) on the glass substrate to form a hole injection layer having a thickness of 100 Å, NPB was deposited on the hole injection layer to form a first hole transport layer having a thickness of 500 Å, TCTA was deposited on the first hole transport layer to form a second hole transport layer having a thickness of 50 Å, and mCP was deposited on the second hole transport layer to form an electron blocking layer having a thickness of 50 Å.

[0582] A first host (Compound H1), a second host (Compound H2), a sensitizer (Compound S-1), and an emitter (Compound 1) were co-deposited on the electron blocking layer to form an emission layer having a thickness of 400 Å. Here, the first host and the second host were mixed at a ratio of 60:40, and the amounts of the sensitizer and the emitter were adjusted to be 15 wt % and 1 wt %, respectively, based on the total weight of the first host, the second host, the sensitizer, and the emitter.

[0583] DBFPO was deposited on the emission layer to form a hole blocking layer having a thickness of 100 Å, DBFPO was deposited on the emission layer to form a hole blocking layer having a thickness of 100 Å, DBFPO and LiQ were co-deposited thereon at a weight ratio of 5:5 to form an electron transport layer having a thickness of 300 Å, LiQ was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, an then, Al was deposited on the electron injection layer to form a cathode having a thickness of 1,000 Å, thereby completing the manufacture of an organic light-emitting device, and then DBFPO and LiQ were co-deposited thereon at a weight ratio of 5:5 to form an electron transport layer having a thickness of 300 Å, and then, LiQ was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and Al was deposited on the electron injection layer to form a cathode having a thickness of 1,000 Å, thereby completing the manufacture of an organic light-emitting device.

##STR02912## ##STR02913##

Comparative Examples 2-1 and 2-2

[0584] Organic light-emitting devices were manufactured in the same manner as in Example 2-1, except that, in forming an emission layer, for use as a sensitizer and a dopant, corresponding compounds shown in Table 7 were used.

Evaluation Example: Evaluation of Organic Light-Emitting Device Characteristics

[0585] The driving voltage, maximum external quantum efficiency, power efficiency, current efficiency, CIE color coordinates (at 1000 nit), conversion efficiency, and full width at half maximum of the organic light emitting devices manufactured in Examples and Comparative Examples above were measured using a current-voltage meter (Keithley 2400) and a luminance meter (Minolta Cs-1000 Å), and results thereof are summarized in Tables 8 and 9.

TABLE-US-00008 TABLE 8 Driving voltage EQE.sub.max Lifespan Dopant (V) (%) (T95) (%) Example 1-1 1 4.46 264 531 Comparative C1 5.56 100 100 Example 1-1

TABLE-US-00009 TABLE 9 Driving voltage EQE.sub.max Lifespan Sensitizer Dopant (V) (%) (T95) (%) Example 2-1 S-1 1 4.19 147 1052 Comparative S-1 C1 4.59 100 100 Example 2-1 Comparative S-1 C2 4.43 74 116 Example 2-2

##STR02914##

[0586] Referring to Tables 8 and 9, it was confirmed that the organic light-emitting device of Examples above had higher efficiency and/or longer lifespan than the organic light-emitting devices of Comparative Examples above.

[0587] In addition, referring to Tables 8 and 9, it was confirmed that the heterocyclic compound was applicable to all organic light-emitting devices that emit light through various mechanisms.

[0588] As described above, according to the one or more embodiments, an organic light-emitting device including a heterocyclic compound may have improved efficiency and/or excellent colorimetric purity.

[0589] It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in one or more embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.