A light emitting element includes a first electrode, a second electrode disposed on the first electrode, and an emission part disposed between the first electrode and the second electrode and including a first emission layer and a second emission layer disposed on the first emission layer, the first emission layer may include a first host, and a first dopant, and the second emission layer may include a hole transport host different from the first host, an electron transport host, and a second dopant. A first hole mobility of the first host may be in a range of about 5.0×10.sup.−6 cm.sup.2/Vs to about 1.0×10.sup.−3 cm.sup.2/Vs, a second hole mobility of a host mixture including the hole transport host and the electron transport host may be in a range of about 1.0×10.sup.−6 cm.sup.2/Vs to about 1.0×10.sup.−4 cm.sup.2/Vs, and the first hole mobility may be larger than the second hole mobility.

An organic compound, having a structure shown in formula (I), is provided. The organic compound includes:

##STR00001## where X and Y are each independently selected from substituted carbon, divalent heteroatom or substituted heteroatom with a valence greater than 2; A and R are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C2-C30 heterocyclic; and when one of A and R is hydrogen or deuterium, another of A and R is not hydrogen or deuterium; and substituents of the substituted carbon, the substituted heteroatom with the valence greater than 2, the substituted C1-C10 alkyl, the substituted C6-C30 aryl and the substituted C2-C30 heterocyclic are each independently selected from one or a combination of deuterium, nitro, cyano, substituted or unsubstituted C1˜C10 alkyl, substituted or unsubstituted C6˜C30 aryl, or substituted and unsubstituted C2˜C30 heterocyclic.

An iridium complex which has a phenylpyridine bidentate ligand containing a group represented by the following general formula (A): ##STR00001##
wherein X represents a cyano group or a halogenated alkyl group; L represents a single bond or a divalent linking group; R represents a substituent; n represents an integer of 0 to 4; * represents a binding site to a phenylpyridine bidentate ligand.

A light-emitting device may include an organometallic compound represented by Formula 1, and an electronic apparatus may include the light-emitting device including the organometallic compound represented by Formula 1. The light-emitting device may further include: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode, the interlayer comprising an emission layer:

##STR00001##

wherein the detailed description of Formula 1 is the same as described in the present specification.

A light emitting diode includes a first electrode, a second electrode disposed on the first electrode, and at least one functional layer disposed between the first electrode and the second electrode. The at least one functional layer includes a compound represented by Formula 1, thereby exhibiting high efficiency and long lifespan.

##STR00001##

ABSTRACT An organic electroluminescence device includes an anode, a cathode, and at least one organic layer provided between the anode and the cathode, in which the at least one organic layer contains a first compound represented by a formula (1) and a second compound represented by a formula (2). In the formula (1), A.sup.1 is a substituted or unsubstituted nitrogen-containing heterocyclic group having 5 to 24 ring atoms, and L.sup.1 is a single bond, a substituted or unsubstituted divalent aryl group having 6 to 24 ring carbon atoms or a substituted or unsubstituted divalent heterocyclic group having 5 to 24 ring atoms. In the formula (2), X.sup.1 is an oxygen atom or a sulfur atom. ##STR00001##

A light-emitting device includes a first light-emitting layer and a second light-emitting layer that are stacked. A material of the first light-emitting layer includes a first host material and a first TADF sensitizer. A material of the second light-emitting layer includes a second host material, a second TADF sensitizer, and a second fluorescent emissive material. Transmission rates of the material of the first light-emitting layer and the material of the second light-emitting layer to holes are greater than transmission rates of the material of the first light-emitting layer and the material of the second light-emitting layer to electrons, and there is a first overlapping region between a normalized electroluminescence spectrum of the first TADF sensitizer and a normalized absorption spectrum of the second fluorescent emissive material.

Provided is a heterocyclic compound of Chemical Formula 1: ##STR00001## wherein: W1 and W2 are the same as or different from each other, and each independently is O or S; A1 and A2 each independently is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; R1 to R7 each independently is hydrogen, deuterium, a nitrile group, a halogen group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; and R1 to R7, A1 and A2 bond to adjacent substituents to form a substituted or unsubstituted ring,
and an organic light-emitting device including the same.

Provided are an organic compound and an application thereof The organic compound of the present disclosure has a structure similar to a spiro ring. The structure can enable the compound to obtain relatively high thermal stability and a relatively high glass transition temperature Tg. The skeleton has an electron-donating ability, and a group having an electron withdrawing ability is linked to the skeleton so that the skeleton has the electron withdrawing ability, which is more conducive to the transport and recombination of electrons and holes in this region. The compound having the structure similar to the spiro ring also has suitable steric distortion and can reduce a molecular acting force and intermolecular stacking, which is conducive to reducing concentration quenching and efficiency roll-off and preparing an organic light-emitting diode (OLED) device. Therefore, the compound of the present disclosure also enables the device to achieve a longer lifetime.

Disclosed is a novel organic electroluminescent compound represented by Formula (I): ##STR00001##
The organic electroluminescent compound is employed as a material for at least one organic layer of an organic electroluminescent device such as a light emitting layer, a hole transport layer, an electron transport layer, an electron blocking layer, and/or a capping layer, achieving excellent luminescent properties (including high luminous efficiency and quantum efficiency) of the device. Also disclosed is an organic electroluminescent device including the organic electroluminescent compound.