TWO DIMENSIONAL BENZO[4,5]IMIDAZO[2,1-A]ISOINDOLEINCORPORATED NON-FULLERENE ELECTRON ACCEPTORS FOR ORGANIC PHOTOVOLTAIC DEVICES
20240343739 ยท 2024-10-17
Inventors
Cpc classification
C08L65/00
CHEMISTRY; METALLURGY
C08G61/12
CHEMISTRY; METALLURGY
C07D495/22
CHEMISTRY; METALLURGY
C08G2261/3246
CHEMISTRY; METALLURGY
H10K30/30
ELECTRICITY
C09D165/00
CHEMISTRY; METALLURGY
C08G2261/3223
CHEMISTRY; METALLURGY
International classification
C07D495/22
CHEMISTRY; METALLURGY
C08G61/12
CHEMISTRY; METALLURGY
Abstract
The present application provides two dimensional benzo[4,5]imidazo[2,1-a]isoindole incorporated non-fullerene electron acceptors having the structure of Formula I (I), and processes for the synthesis and manufacture thereof. Also provided are semiconductor materials, polymers, oligomers, films and membranes incorporating the non-fullerene acceptor of Formula (I), and the optoelectronic devices made therefrom.
##STR00001##
Claims
1. A compound of Formula I. ##STR00031## wherein: R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same or different and each is independently F, H, Cl, Br, I, a substituted or unsubstituted C.sub.1-C.sub.12-alkyl, a substituted or unsubstituted C.sub.1-C.sub.12-alkoxy, a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group; each R.sup.5 is independently a substituted or unsubstituted C.sub.1-C.sub.30-alkyl group; each R.sup.6 is independently a substituted or unsubstituted C.sub.1-C.sub.30-alkyl group; each Y is independently C(CN).sub.2 or O; A and A together with the carbons to which they are attached form an aromatic or heteraromatic ring; and B and B together with the carbons to which they are attached form an aromatic or heteraromatic ring.
2. The compound of claim 1, wherein A and A together with the carbons to which they are attached form an aromatic or heteraromatic moiety that is: ##STR00032## where the asterisks show the point of attachment; and/or B and B together with the carbons to which they are attached form an aromatic or heteraromatic ring, for example, B and B together with the carbons to which they are attached form an aromatic or heteraromatic moiety that is: ##STR00033## where the asterisks show the point of attachment; wherein: R.sup.7, R.sup.8, R.sup.9 and R.sup.10 are each the same or different and are independently F, H, Cl, Br, I, a C.sub.1-C.sub.12-alkyl or a C.sub.1-C.sub.12-alkoxy group; Z is O, S, Se, or NR, where R is a C.sub.1-C.sub.12-alkyl; and R.sup.11 to R.sup.20 are each the same or different and are independently F, H, Cl, Br, I, a C.sub.1-C.sub.12-alkyl or a C.sub.1-C.sub.12-alkoxy group.
3. The compound of claim 1, wherein Y is C(CN).sub.2.
4. The compound of claim 1, wherein R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, optionally a branched C.sub.8-alkyl or a branched C.sub.12 alkyl.
5. The compound of claim 1, wherein R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.11 alkyl.
6. The compound of claim 1, wherein one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H.
7. The compound of claim 6, wherein R.sup.3 is a t-butyl.
8. The compound of claim 1, having the structure of Formula (II), Formula (III), Formula (IV), Formula (V) or Formula (VI): ##STR00034## ##STR00035##
9. The compound of claim 8, which is a compound of Formula II, wherein R7 and R8 are both H and R9 and R10 are each independently H, Cl or F.
10. The compound of claim 9, where each R9 and R10 are the same and are either Cl or F, preferably F.
11. A semiconductor material comprising the compound according to claim 1 in combination with an electron donor polymer.
12. The semiconductor material according to claim 11, wherein the polymer donor is a middle bandgap donor polymer, such as PM6.
13. The semiconductor material according to claim 11, which is a bulk heterojunction organic material.
14. The semiconductor material according to claim 11, wherein the semiconductor material is a component in an organic electronic device, such as an optoelectronic device, an electroluminescence device, a field effect transistor, an optical sensor, a photovoltaic device, or a thermoelectric device.
15. A polymer or an oligomer comprising the compound according to claim 1 copolymerized with an electron-donating comonomer or an electron-withdrawing co-monomer.
16. The polymer or oligomer according to claim 15 having a ratio of electron-accepting monomer to electron-donating or electron-withdrawing co-monomer in a range of from 1:99 to 99:1 mol %.
17. The polymer or oligomer according to claim 15, comprising from 2 to 20,000 monomeric units.
18. The polymer or oligomer according to claim 15, comprising the electron-donating co-monomer, which is one or more of a substituted or unsubstituted phenyl, thiophene, fluorene, carbazole, benzodithiophene, pyrrole, indenofluorene, indolocarbazole, dibenzosilole, dithienosilole, benzo[1,2-b;3,4-b]dithiophene, benzo[2,1-b:3,4-b]dithiophene, cyclopenta[2,1-b:3,4-b]dithiophene, thieno[3,2-b]thiophene, thieno[3,4-b]thiophene or dithieno[3,2-b:2,3-d]pyrrole, where the substituent, if present, is one or more of F, a C.sub.1-C.sub.30-alkyl, C.sub.1-C.sub.30-alkenyl, C.sub.1-C.sub.30-alkynyl, a C.sub.5-C.sub.30-aryl group, or a C.sub.3-C.sub.30-heteroaryl group having one or more of N, O or S in the ring.
19. The polymer or oligomer according to claim 15, comprising the electron-withdrawing co-monomer, which is one or more of 2,1,3-benzothiadiazole, 2H-benzo[d][1,2,3]triazole, benzo[c][1,2,5]oxadiazole, benzo[c][1,2,5]selenadiazole, diketopyrrolo[3,4-c]pyrrole-1,4-dione, ester or ketone substituted thieno[3,4-b]thiophene, thieno[3,4-c]pyrrole-4,6-dione, isoindigo, or quinoxaline, where the substituent, if present, is one or more of F, a C.sub.1-C.sub.30-alkyl, C.sub.1-C.sub.30-alkenyl, C.sub.1-C.sub.30-alkynyl, a C.sub.6-C.sub.30-aryl group or a C.sub.3-C.sub.30-heteroaryl group having one or more of N, O or S in the ring.
20. A film or membrane comprising the compound of claim 1.
21. An optoelectronic device comprising the semiconductor material of claim 11.
22. The optoelectronic device according to claim 21, which is an electroluminescence device, a field effect transistor, an optical sensor, a photovoltaic device, or a thermoelectric device.
23. A process for synthesizing a compound of Formula (I), as defined in claim 1, comprising the steps of: a) reducing the compound of Formula (VII), optionally with LiAlH4, ##STR00036## to produce the compound of Formula (VIII) ##STR00037## b) treating the compound of Formula (VIII) with a phthalic hydride of Formula (IX) ##STR00038## to form a compound of Formula (X) ##STR00039## and c) reacting the compound of Formula (X) with a compound of Formula (XI) and/or a compound of Formula (XII) ##STR00040## to produce the compound of Formula (I), wherein R.sup.1-R.sup.6, A, A, B, B and Y are as defined in claim 1.
Description
BRIEF DESCRIPTION OF THE FIGURES
[0039] For a better understanding of the application as described herein, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
DETAILED DESCRIPTION
Definitions
[0049] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
[0050] As used in the specification and claims, the singular forms a, an and the include plural references unless the context clearly dictates otherwise.
[0051] The term comprising as used herein will be understood to mean that the list following is non-exhaustive and may or may not include any other additional suitable items, for example one or more further feature(s), component(s) and/or ingredient(s) as appropriate.
[0052] Reference throughout this specification to one embodiment, an embodiment, another embodiment, a particular embodiment, a related embodiment, a certain embodiment, an additional embodiment, or a further embodiment or combinations thereof means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the foregoing phrases in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0053] As used herein, the term substituted refers to at least one hydrogen atom of a functional group being replaced with a non-hydrogen group, provided that normal valencies are maintained and that the substitution results in a stable compound. When a group is noted as being substituted, the substituents are selected from the exemplary group including, but not limited to, halo (e.g., chloro, fluoro or bromo), oxy, carboxy, hydroxy, amino, amido, nitro, thio, C.sub.1-C.sub.30-alkyl, C.sub.2-C.sub.30-alkenyl, C.sub.2-C.sub.30-alkynyl, C.sub.6-C.sub.30-aryl, C.sub.6-C.sub.30-heteroaryl having one or more N, O or S in the ring, C.sub.7-C.sub.36-alkaryl, C.sub.1-C.sub.30-alkoxy, C.sub.2-C.sub.30-alkenoxy, C.sub.2-C.sub.30-alkynoxy, C.sub.6-C.sub.30-aryloxy, C.sub.1-C.sub.30-alkylamino, C.sub.2-C.sub.60-dialkylamino, C.sub.1-C.sub.30-alkamido, C.sub.2-C.sub.30-carboxy or C.sub.1-C.sub.30-carbonyl, and mixtures thereof and the like. In some embodiments, the substituents are selected from the group halo (e.g., chloro, fluoro or bromo), oxy, carboxy, hydroxy, nitro, thio, C.sub.1-C.sub.20-alkyl, C.sub.2-C.sub.20-alkenyl, C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.20-aryl, C.sub.6-C.sub.20-heteroaryl having one or more N, O or S in the ring, C.sub.7-C.sub.24-alkaryl, C.sub.1-C.sub.20-alkoxy, C.sub.2-C.sub.20-alkenoxy, C.sub.2-C.sub.20-alkynoxy, C.sub.6-C.sub.20-aryloxy, C.sub.2-C.sub.40-dialkylamino, C.sub.2-C.sub.20-carboxy or C.sub.1-C.sub.20-carbonyl, and mixtures thereof.
[0054] As used herein, the term alkyl, unless otherwise specified, is intended to have its accustomed meaning of a straight or branched chain, saturated hydrocarbon, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, t-butyl, n-pentyl, sec-pentyl, t-pentyl, neopentyl, and the like. In some embodiments, alkyl groups have from 1 to 30 carbon atoms, or 1 to 20 carbon atoms, or from 1 to 12 carbon atoms, or from 1 to 8 carbon atoms, or from 1 to 6 carbon atoms. As used herein, the term C.sub.2-C.sub.30 alkyl refers to an alkyl group, as defined above, containing at least 2, and at most 30, carbon atoms. The term cycloalkyl as used herein, is also intended to have its accustomed meaning of a cyclic, saturated hydrocarbon, such as, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, or the like. In some embodiments, cycloalkyl groups have from 3 to 10 carbon atoms, or from 3 to 8 carbon atoms, or from 3 to 6 carbon atoms, or 5 or 6 carbon atoms. A substituted alkyl or substituted cycloalkyl includes one or more substituent, as defined above. Preferably, a substituted alkyl or substituted cycloalkyl includes one or two substituents, as defined above.
[0055] As used herein, the term alkenyl refers to a hydrocarbon group, e.g., from 2 to 30 carbon atoms, or from 2 to 20 carbon atoms, or from 2 to 12 carbon atoms, and having at least one carbon-carbon double bond. Non-limiting examples of alkenyl, as used herein include, vinyl (ethenyl), propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl, and isobutenyl. As used herein, the term C.sub.2-C.sub.30 alkenyl refers to an alkenyl group, as defined above, containing at least 2, and at most 30, carbon atoms.
[0056] As used herein, the term alkynyl refers to a hydrocarbon group, e.g., from 2 to 30 atoms, or from 2 to 20 carbon atoms, or from 2 to 12 carbon atoms, and having at least one carbon-carbon triple bond. Non-limiting examples of alkynyl, as used herein, include but are not limited to ethynyl (acetylenyl), 1-propynyl, 1-butynyl, 2-butynyl, 1-pentynyl, and 1-hexynyl. As used herein, the term C.sub.2-C.sub.3M alkynyl refers to an alkynyl group, as defined above, containing at least 2, and at most 30, carbon atoms.
[0057] As used herein, the term alkoxy refers to the group R.sub.aO, where R.sub.a is alkyl as defined above and the term C.sub.1-C.sub.12 alkoxy refers to the group R.sub.aO, where R.sub.a is C.sub.1-C.sub.12 alkyl as defined above. Non-limiting examples of alkoxy are methoxy, ethoxy, propyloxy, and isopropyloxy.
[0058] As used herein, the term aryl, unless otherwise specified, is intended to mean an aromatic hydrocarbon system, for example, phenyl, naphthyl, phenanthrenyl, anthracenyl, pyrenyl, and the like. Included within the term aryl are heteroaryl groups including one or more heteroatom (e.g., N, O or S), preferably 1 to 3 heteroatoms, in the aromatic system. In some embodiments, aryl or heteroaryl groups have from 6 to 30 carbon atoms, or from 6 to 18 carbon atoms, or from 6 to 14 carbon atoms, or from 6 to 10 carbon atoms. Non-limiting examples of aryl include phenyl, biphenyl, naphthyl and anthracyl and non-limiting examples of the heteroaryl groups include pyridinyl, pyridazinyl, pyrimidyl, pyrazyl, triazinyl, pyrrolyl, pyrazolyl, imidazolyl, (1,2,3,)-triazolyl, (1,2,4)-triazolyl, pyrazinyl, pyrimidinyl, tetrazolyl, furyl, thienyl, isoxazolyl, thiazolyl, isoxazolyl, oxazolyl, benzofuranyl, benzothiophenyl, indolyl, 1H-indazolyl, indolinyl, benzopyrazolyl, 1,3-benzodioxolyl, benzoxazolyl, quinolinyl, isoquinolinyl, benzimidazolyl, quinazolinyl, pyrido[2,3-b]pyrazinyl, pyrido[3,2-c]pyridazinyl, pyrido[3,4-b]-pyridinyl, quinoxalinyl, 1,4-benzisoxazinyl, and benzothiazolyl. A substituted aryl or substituted heteroaryl includes one or more substituent, as defined above. Preferably, a substituted aryl or substituted heteroaryl includes one or two substituents, as defined above.
[0059] The present inventors have developed a series of non-fullerene acceptors (NFAs) based on the electron-withdrawing core, 5a,9a-dihydro-11H-benzo[4,5]imidazo[2,1-a]isoindol-11-one (BIID). With reference to
[0060] In addition, ? extension in the acceptor end groups of the BIID-based NFA compound of the present invention can improve optical absorption and/or improve ?-? stacking to enhance film ordering and carrier mobility. The optional incorporation of halogens, for example, fluorines, in the acceptor end groups of these NFA compounds can be used to further suppress charge recombination loss.
[0061] The BIID-based NFA compounds of the present application have a larger ?-conjugation than Y6 and include versatile functional groups that are suitable for chemical modification in order to further optimize the NFA for different applications and/or for improved performance. For example, tunability of the BIID-based NFA compounds is further achieved by incorporating different side chain moieties and functional groups in the central core. In contrast, similar modifications cannot be incorporated in Y6 because of the lack of reaction sites.
[0062] The present BIID-based NFAs perform well in OPVs. Without wishing to be bound by theory, this is credited to the high V.sub.OC obtained, which benefits mainly from the suppressed trap-assisted recombination. The BIID core-based molecular design allows further electronic property tuning, precise morphology optimization, and solution processability, for example, for the use in next-step high performance indoor OPVs.
[0063] The present application provides BIID-based NFA compounds having the general chemical structure of Formula I
##STR00013##
wherein: [0064] R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same or different and each is independently F, H, Cl, Br, I, a substituted or unsubstituted C.sub.1-C.sub.12-alkyl, a substituted or unsubstituted C.sub.1-C.sub.12-alkoxy, a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group; [0065] each R.sup.5 is independently a substituted or unsubstituted C.sub.1-C.sub.30-alkyl group; [0066] each R.sup.6 is independently a substituted or unsubstituted C.sub.1-C.sub.30-alkyl group; [0067] each Y is independently C(CN).sub.2 or O; [0068] A and A together with the carbons to which they are attached form an aromatic or heteraromatic ring, for example, A and A together with the carbons to which they are attached form an aromatic or heteraromatic moiety that is:
##STR00014##
where the asterisks show the point of attachment; [0069] B and B together with the carbons to which they are attached form an aromatic or heteraromatic ring, for example, B and B together with the carbons to which they are attached form an aromatic or heteraromatic moiety that is:
##STR00015##
where the asterisks show the point of attachment; [0070] wherein: [0071] R.sup.7, R.sup.8, R.sup.9 and R.sup.10 are each the same or different and are independently F, H, Cl, Br, I, a C.sub.1-C.sub.12-alkyl or a C.sub.1-C.sub.12-alkoxy group; [0072] Z is O, S, Se, or NR, where R is a C.sub.1-C.sub.12-alkyl; and [0073] R.sup.11 to R.sup.20 are each the same or different and are independently F, H, Cl, Br, I, a C.sub.1-C.sub.12-alkyl or a C.sub.1-C.sub.12-alkoxy group.
[0074] In a specific embodiment there is provided a compound of Formula (I), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.12alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.11 alkyl.
[0075] In some embodiments of the compound of Formula (I), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl.
[0076] In accordance with some embodiments of the present application, the BIID-based NFA compound has the structure of Formula II:
##STR00016##
wherein R.sup.1-R.sup.10 and Y are as defined above.
[0077] In a specific embodiment there is provided a compound of Formula (II), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.12alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.1 alkyl.
[0078] In some embodiments of the compound of Formula (II), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl.
[0079] In some embodiments of the compound of Formula (II), the R.sup.7 and R.sup.8 groups are H and the R.sup.9 and R.sup.10 groups are each independently H, Cl or F, or all of the R.sup.9 and R.sup.10 groups are the same and are H, Cl or F.
[0080] In accordance with some embodiments of the present application, the BIID-based NFA compound has the structure of Formula (III):
##STR00017##
[0081] In a specific embodiment there is provided a compound of Formula (III), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.12alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.1 alkyl.
[0082] In some embodiments of the compound of Formula (III), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl. Optionally, each of R.sup.11 and R.sup.12 are H.
[0083] In accordance with some embodiments of the present application, the BIID-based NFA compound has the structure of Formula (IV):
##STR00018##
[0084] In a specific embodiment there is provided a compound of Formula (IV), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.2alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.1 alkyl.
[0085] In some embodiments of the compound of Formula (IV), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl. In some embodiments, R.sup.12 is H or a C.sub.1-C.sub.8 alkyl, and R.sup.11 is F.
[0086] In accordance with some embodiments of the present application, the BIID-based NFA compound has the structure of Formula (V):
##STR00019##
[0087] In a specific embodiment there is provided a compound of Formula (V), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.12 alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.1 alkyl.
[0088] In some embodiments of the compound of Formula (V), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl. In some embodiments R.sup.14 is H or a C.sub.1-C.sub.8 alkyl, and R.sup.13 is F.
[0089] In accordance with some embodiments of the present application, the BIID-based NFA compound has the structure of Formula (VI):
##STR00020##
[0090] In a specific embodiment there is provided a compound of Formula (VI), wherein Y is C(CN).sub.2. In some examples, R.sup.5 is a branched C.sub.6-C.sub.20 alkyl, for example, a branched C.sub.8-alkyl or a branched C.sub.12 alkyl, and R.sup.6 is a C.sub.6-C.sub.20 alkyl, such as a linear C.sub.1 alkyl.
[0091] In some embodiments of the compound of Formula (VI), one of R.sup.1-R.sup.4 is a C.sub.1-C.sub.6 alkyl, such as a methyl, ethyl, propyl, or butyl, and the other three are H. Optionally, R.sup.3 is a t-butyl. In some embodiments, each of R15-R20 are independently H or a C.sub.1-C.sub.12 alkyl.
[0092] Certain of the compounds described herein may contain one or more chiral atoms, or may otherwise be capable of existing as two enantiomers. The compounds of this application include mixtures of enantiomers as well as purified enantiomers or enantiomerically enriched mixtures. Also provided herein are the individual isomers of the compounds represented by formula (I) above as well as any wholly or partially equilibrated mixtures thereof. The present application also covers the individual isomers of the compounds represented by the formulas above as mixtures with isomers thereof in which one or more chiral centers are inverted.
[0093] The presence of a double bond is possible in the compounds described herein, accordingly also included in the present BIID-based NFA compounds are their respective pure E and Z geometric isomers as well as mixtures of E and Z isomers, without any limiting ratios set on prevalence of Z to E isomers.
Synthesis
[0094] The present BIID-based NFA compounds can be prepared using various synthetic methods. Provided herein is a process for synthesis of an embodiment of the compound of Formula I (in which B is the same as A, and B is the same and A) according to the reactions shown in Scheme I:
##STR00021##
[0095] The specific reaction conditions, starting materials and reagents will change depending on the structure of the target compound of Formula I. It should be understood that selection of the specific reaction conditions, starting materials, and reagents used in the synthetic process of Scheme I would be a matter of routine for the skilled person. The starting material used may be a derivative of the precursor used in the synthesis of Y6. Such compounds are commercially available, as are various phthalic hydride derivatives used in the second step of the process of Scheme 1. Similarly, suitable compounds used to introduce functionality in the acceptor end groups are either commercially available or readily derivable from commercially available compounds.
[0096] Accordingly, also provided herein is a process for synthesizing the compound of Formula (I) comprising the steps of: [0097] (a) reducing the compound of Formula (VII), optionally with LiAlH.sub.4,
##STR00022## [0098] to produce the compound of Formula (VIII)
##STR00023## [0099] (b) treating the compound of Formula (VIII) with a phthalic hydride of Formula (IX)
##STR00024## [0100] to form a compound of Formula (X)
##STR00025##
and [0101] (c) reacting the compound of Formula (X) with a compound of Formula (XI) and/or a compound of Formula (XII)
##STR00026## [0102] to produce the compound of Formula (I), wherein R.sup.1-R.sup.6, A, A, B, B and Y are as defined above.
Semiconductor Materials
[0103] The BIID-based NFAs are useful as n-type semiconductors, for example, in bulk heterojunction organic electronic devices.
[0104] Bulk heterojunction organic material is made from the combination of one or more BIID-based NFA compound, as described herein, with a donor polymer which has a complementary absorption to the NFA compound. The resulting material is an interpenetrating material in which the BIID-based NFA compounds are intimately mixed, allowing interfaces at appropriate diffusion distance to be dispersed across the active layer. The material is manufactured using standard techniques, to have an appropriate thickness necessary for light absorption in the electronic device.
[0105] In one embodiment, a bulk heterojunction blend film can be prepared by dissolving a BIID-based NFA and a donor polymer in an appropriate solvent at different weight ratios, and then casting films by spin-coating. Selection of the appropriate solvent and weight ratios will be dependent on the ultimate application and materials used and their selection is a matter of routine for the skilled person.
[0106] The donor polymer used in the manufacture of semiconductor material comprising the BIID-based NFA can be, for example, a middle bandgap donor polymer, such as, but not limited to, PTQ10, J52, and PCDTBT. In a specific embodiment PBDB-T-2F (PM6) is employed as a donor polymer used together with a BIID-based NFA in the manufacture of semiconductor material in organic electronic devices. Combination of PM6 with a BIID-based NFA can be used to manufacture bulk heterojunction material as an alternative to Y6-PM6 blends. As demonstrated in the following examples, use of the BIID-based NFA compounds described herein in a blend with PM6 produces bulk semiconductor material with improved properties over Y6-PM6 materials. These examples demonstrate the effectiveness of the present BIID-based NFA as an n-type acceptor.
[0107] In another embodiment, the BIID-based NFA can be blended with high-performance p-type materials, such as those described in U.S. Pat. No. 8,927,684, which is incorporated herein by reference in its entirety.
[0108] In another embodiment, the semiconductor material comprises one or more BIID-based NFA in a copolymer with other monomers to yield electron-accepting polymers or oligomers. Among organic semiconductors, alternating conjugated polymers of an electron donor (ED) unit and an electron acceptor (EA) unit have attracted more and more attention due to their special properties associated with the donor/acceptor (D/A) structure in the main chain. This D/A structure can effectively lower the band gap of conjugated polymers. Such alternating conjugated polymers can be prepared using one or more BIID-based NFA as the acceptor monomer(s), alone or in combination with one or more additional acceptor monomer(s). BIID-based NFAs, as described herein, can be used as monomers to produce conjugated oligomers or polymers by generally known methods, for example, by Suzuki coupling or Stille coupling.
[0109] In one example of this embodiment, the BIID-based NFA monomers are end-capped with Br atoms, and the resulting BIID-based NFA dibromides are then polymerized with aromatic distannyl compounds by a Stille coupling reaction or with aromatic diboronic ester by a Suzuki coupling reaction. These are widely used polymerization methods for the preparation of conjugated polymers that would readily performed by the skilled person. In some embodiments, the BIID-based NFA copolymer or oligomers can be used to fabricate OPVs.
[0110] Exemplary groups of co-monomers having electron-donating properties include substituted or unsubstituted phenyls, thienes, fluorenes, carbazoles, benzodithiophenes, pyrroles, indenofluorenes, indolocarbazoles, dibenzosiloles, dithienosiloles, benzo[1,2-b;3,4-b]dithiophenes, benzo[2,1-b:3,4-b]dithiophenes, cyclopenta[2,1-b:3,4-b]dithiophenes, thieno[3,2-b]thiophenes, thieno[3,4-b]thiophenes and dithieno[3,2-b:2,3-d]pyrroles, where any substituents may be one or more of the substituents as defined previously. Specific examples of co-monomers having electron-donating properties include 2,7-bis(4,4,5,5,-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-di(2-ethylhexyl)-fluorene, fluorene, carbazole and benzodithiophene.
[0111] Some examples of electron-accepting monomers include substituted or unsubstituted benzothiadiazole, thienopyrazine, quinoxaline, dihydropyrrolo[3,4-]pyrrole-1,4-dione, thieno[3,4-b]thiophene, where any substituents may be one or more of the substituents as defined previously.
[0112] Electron-accepting monomers may be copolymerized with electron-donating monomers in various ratios to tune the electronic properties of the resulting oligomer or polymer. The ratio of electron-accepting monomer to electron-donating monomer may be in a range of from 1:99 to 99:1 mol %, preferably 40:60 to 60:40 mol %. In oligomers or polymers where other electron-accepting monomers are present, the ratio of BIID-based NFA monomers from to the other electron-accepting monomers is optionally 99:1 to 10:90 mol %.
[0113] Oligomers and polymers of the present invention optionally have from 2 to 20,000 monomeric units, or from 10 to 10,000 monomeric units.
[0114] Oligomers and polymers of the present invention may be cast as thin films or membranes by methods generally known in the art, for example, spin-coating, casting or printing, which can be used for assembly into organic electronic devices.
[0115] Any of the semiconductor materials described herein, comprising one or more BIID-based NFA, can be incorporated in an organic electronic device (e.g., an organic photovoltaic cell). Accordingly, the present application further provides an organic electronic device, comprising the semiconductor material made with a BIID-based NFA and a donor polymer or made using a BIID-based NFA-containing co-polymer. Such organic electronic devices can be, for example, an optoelectronic device, an electroluminescence device, a field effect transistor, an optical sensor, a photovoltaic device (e.g., a solar cell), or a thermoelectric device.
[0116] To gain a better understanding of the invention described herein, the following examples are set forth. It should be understood that these examples are for illustrative purposes only. Therefore, they should not limit the scope of this invention in any way.
EXAMPLES
Example 1: Synthesis and Use of an NFA Having a 5a,9a-dihydro-11H-benzo[4,5]imidazo[2,1-a]isoindol-11-one (BIID) Core Structure
[0117] In the present Example an NFA was synthesized based on the electron-withdrawing core, 5a,9a-dihydro-11H-benzo[4,5]imidazo[2,1-a]isoindol-11-one (Scheme 2). The synthesized BIID-based NFA can be used as n-type semiconductor, for example, in bulk heterojunction solar cells. As a preliminary result, a PCE of 11.2% with a high V.sub.OC of 0.95 V was achieved with the synthesized BIID-based NFA when blended with PM6. Compared with the device performance from the benchmark NFA Y6 in the same configuration, the overall PCE is comparable but the V.sub.OC has been significantly increased by 17% to 0.95 V (0.81 V for the PM6:Y6 blend). The UV-Vis spectroscopy and cyclic voltammetry study showed both NFAs have almost the same E.sub.g and HOMO/LUMO levels, however, the obtained increase in V.sub.OC indicates that this BIID-based NFA is able to suppress the recombination losses, which are the main cause of large energy loss in OPVs. Moreover, similar BIID-based NFAs comprising additional solubilizing side chains attached to the BIID core can be synthesized using the same synthetic approach as described in this Example. The solubility of the resulting NFAs can thus be adjusted with relative ease for the printing process.
##STR00027##
Synthesis of Compound 2
[0118] Y6 precursor and LiAlH.sub.4 were added to an argon protected flask. Then anhydrous THF was added and the reaction mixture was stirred under reflux overnight. Upon cooling to room temperature, the reaction solution was poured into saturated NH.sub.4Cl aqueous solution. Water and ethyl acetate were added for extraction. The organic layer was separated and dried over MgSO.sub.4. After removal of the solvent, crude compound 1 was obtained without further purification. To the flask containing compound 1 AcOH and phthalic anhydride were added and the reaction mixture was stirred under reflux for 6 hrs. Then the solvent was removed and Ac.sub.2O was added. The reaction mixture was then stirred under reflux for 8 hrs. The heating was withdrawn and the solution was let stand still overnight. The precipitate was collected by filtration and washed with methanol. Then the crude product was subject to silica gel column chromatography to give compound 2, which are two separated isomers. .sup.1H NMR (C.sub.6D6, 600 MHz), ? (ppm): ? 7.63 (d, J=1.8 Hz, 1H), 7.42 (d, J=6.0 Hz, 1H), 6.97 (dd, J=6.0, 1.8 Hz, 1H), 6.70 (s, 1H), 6.67 (s, 1H), 4.86-4.73 (m, 4H), 2.72 (t, J=7.8 Hz, 2H), 2.61 (t, J=7.8 Hz, 2H), 2.21-2.10 (m, 2H), 1.86-1.67 (m, 4H), 1.44-1.15 (m, 34H), 1.02 (s, 9H), 1.00-0.71 (m, 18H), 0.69-0.50 (m, 12H).
Synthesis of Compound 3
[0119] To a solution of 2 in DMF and ClCH.sub.2CH.sub.2Cl, POCl.sub.3 was added slowly at 0? C. under argon after being stirred for 1 h at 0? C., the solution was refluxed overnight. Then it was poured into DI water and extracted with dichloromethane. After removal of the solvent, the crude product was purified by silica gel column chromatography to give compound 3. .sup.1H NMR (C.sub.6D6, 600 MHz), ? (ppm): ? 10.01 (s, 1H), 9.97 (s, 1H), 7.64 (s, 1H), 7.42 (d, J=7.8 Hz, 1H), 6.99 (dd, J=7.8, 1.8 Hz, 1H), 4.75-4.65 (m, 4H), 2.82 (t, J=7.8 Hz, 2H), 2.72 (t, J=7.8 Hz, 2H), 2.11-2.00 (m, 2H), 1.78-1.60 (m, 4H), 1.42-1.14 (m, 34H), 1.03 (s, 9H), 1.00-0.71 (m, 18H), 0.64-0.48 (m, 12H).
Synthesis of BIID2
[0120] 3 and INCN-2F were mixed in a flask. Then chloroform and pyridine were added. (The reaction mixture was stirred under reflux overnight. Then solvent was removed and the crude product was subject to silica gel column chromatography to give BIID2. .sup.1H NMR (CD.sub.2Cl.sub.2, 600 MHz), ? (ppm): ? 9.13 (s, 2H), 8.56-8.50 (m, 2H), 7.89 (s, 1H), 7.75-7.67 (m, 4H), 4.80-4.70 (m, 4H), 3.30-3.19 (m, 4H), 2.04-1.94 (m, 2H), 1.93-1.83 (m, 4H), 1.43 (s, 9H), 1.42-1.07 (m, 34H), 1.05-0.81 (m, 18H), 0.79-0.57 (m, 12H).
Optoelectronic Properties of BIID2
[0121] The absorption profile of BIID2 was characterized by UV-Vis absorption spectroscopy. Both the spin-coated film and solution (in chloroform) were measured (
OPV Performance
[0122] To evaluate the PV performance of BIID2, it was with PM6 as the active layer in an inverted device structure (ZnO as the electron injection layer and MoO.sub.3 as the hole injection layer). The active area was 1 cm.sup.2. The current-voltage (J-V) characteristics were measured in air under air mass 1.5 global (AM 1.5G) irradiation of 100 mW/cm.sup.2. The J-V curves and EQE spectrum of the fabricated solar cell are shown in
Example 2: A Non-Fullerene Acceptor Based on a Two-Dimensional Electron-Deficient Core for Organic Photovoltaic Cells
[0123] In this Example, the BIID core structure was as the basis for an acceptor molecule with increased optical bandgap, in comparison to Y6, and to finely tuned energy levels to increase the V.sub.oc of each individual cell. Specifically, the BIID core structure was modified by extending the centre electron-deficient core in the y-direction and changing the C.sub.8-alkyl chain to C.sub.12-alkyl chain, to synthesize a new two-dimensional NFA: 2,2-((2Z,2Z)-((16,17-bis(2-butyloctyl)-10-oxo-3,13-diundecyl-4c,11a,16,17-tetrahydro-10H-isoindolo[2,1:1,2]imidazo[4,5-e]thieno[2,3:4,5]thieno[2,3:4,5]pyrrolo[3,2-g]thieno[2,3:4,5]thieno[3,2-b]indole-2,14-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (BIID3).
##STR00028##
[0124] BIID3 has an optical bandgap of 1.38 eV, which is slightly larger than that of Y6 (1.31 eV). It is interesting to point out that cyclic voltammetry measurements show that BIID3 has HOMO/LUMO levels of ?5.68/?4.04 eV in the thin film state, which are similar to those of Y6 (5.71/?4.05 eV). BIID3 was tested with the donor polymer PM6 in a 1 cm.sup.2 inverted OPV device and achieved high PCE of 13.7% under one sun irradiation and 19.4% under an indoor LED illumination.
##STR00029##
[0125] The overall synthesis of BIID3 consisted of three major steps (Scheme 3).
##STR00030##
[0126] First, the starting material EA634 was reduced and then reacted with phthalic anhydride to yield 2. Then the aldehyde functional groups were introduced by treating 2 with POCl.sub.3 and DMF to generate 3. Finally, the condensation of 3 and INCN-2F gave the product BIID3.
[0127] The thermal stability of BIID3 was characterized by by Thermogravimetric Analysis (TGA). An onset decomposition temperature of 300? C. corresponding to a 1% weight loss was found. The absorption profile of BIID was characterized by UV-Vis absorption spectroscopy. Both the spin-coated film and solution (in chloroform) were measured (
[0128] To evaluate the photovoltaic performance of BIID3, it was blending with PM6 as the active layer in an inverted OPV device structure (ZnO as the electron extraction layer and MoO.sub.3 as the hole extraction layer). The active area was 1 cm.sup.2. A comparison device was fabricated using Y6:PM6 as the active layer and evaluated under the same conditions for comparison. The devices were first investigated under AM 1.5 G irradiation of 100 mW/cm.sup.2 in the air. The J-V curves and EQE spectra of the fabricated OPV devices are shown in
[0129] The charge mobilities of these two devices were also measured. The BIID3 device had an electron mobility of 8.73?10.sup.?5 cm.sup.2/V s, and Y6 had an electron mobility of 9.66?10.sup.?5 cm.sup.2/V s. The EQE spectra showed that there is blue shift for the BIID3 containing device, which is partially responsible for the slightly smaller current density.
[0130] Following previous studies on indoor OPVs,.sup.32-34 the photovoltaic performance of the OPV devices were measured under different LED light intensities from 56 lux to 1300 lux (Tables 2 and 4). As shown in these Tables, the PCEs of the OPV devices increase as the light intensity increases in this light intensity range. This is because the increased carrier density at a higher light intensity reduces the effect of leakage current and trap-assisted recombination. At an illumination of 1300 lux, the BIID3-based device showed a PCE of 19.4% with a V.sub.OC of 0.75 V, J.sub.SC of 153 ?A/cm.sup.2 and an FF of 0.70 while the Y6-based device showed a PCE of 17.5% with a V.sub.OC of 0.66 V, J.sub.SC of 157 ?A/cm.sup.2 and an FF of 0.70 (
TABLE-US-00002 TABLE 2 Device Parameters for the BIID3 Device LED light LED light intensity intensity (Lux) (?W/cm.sup.2) PCE (%) J.sub.SC (?A/cm.sup.2) V.sub.OC (V) FF 1300 412 19.4 153.0 0.75 0.70 768 241 19.0 86.7 0.73 0.73 505 159 18.7 58.1 0.72 0.71 409 128 18.6 47.3 0.71 0.71 334 105 18.4 38.9 0.70 0.71 201 63 18.1 23.5 0.68 0.71 100 32 17.2 11.8 0.66 0.70 56 18 16.6 6.7 0.64 0.70
TABLE-US-00003 TABLE 3 Device Parameters for the Y6 Device LED light LED light intensity J.sub.SC intensity (Lux) (?W/cm.sup.2) PCE (%) (?A/cm.sup.2) V.sub.OC (V) FF 1311 414 17.5 157.3 0.66 0.70 768 241 17.0 91.1 0.64 0.70 501 158 16.6 60.5 0.62 0.70 407 128 16.4 49.2 0.61 0.70 266 83 16.1 32.3 0.60 0.69 202 64 15.5 24.6 0.59 0.68 101 32 14.9 12.4 0.56 0.69 57 18 14.5 7.0 0.53 0.68
[0131] The dependence of J.sub.SC on the light intensity was evaluated in
CONCLUSIONS
[0132] The present example describes the synthesis of a BIID-based NFA using the two-dimensional rigid fused electron deficient BIID core. This compound has a larger n-conjugation than Y6 and includes versatile functional groups that are suitable for chemical modification in order to further optimize the NFA for different applications.
[0133] The OPV device based on BIID3:PM6 showed a decent PCE of 13.7% under the one sun irradiation and a high PCE of 19.4% under the LED illumination. This good performance of the BIID3 in OPVs is credited to its high V.sub.OC, which benefits mainly from the suppressed trap-assisted recombination. The BIID core-based molecular design allows further electronic property tuning, precise morphology optimization, and solution processability for the use in next-step high performance indoor light OPVs.
REFERENCES
[0134] (1) Yu, G.; Gao, J.; Hummelen, J. C.; Wudl, F.; Heeger, A. J. Polymer Photovoltaic Cells: Enhanced Efficiencies via a Network of Internal Donor-Acceptor Heterojunctions. Science (80-.). 1995, 270 (5243), 1789-1791. https://doi.org/10.1126/science.270.5243.1789. [0135] (2) Kaltenbrunner, M.; White, M. S.; Glowacki, E. D.; Sekitani, T.; Someya, T.; Sariciftci, N. S.; Bauer, S. Ultrathin and Lightweight Organic Solar Cells with High Flexibility. Nat. Commun. 2012, 3 (1), 770. https://doi.org/10.1038/ncomms1772. [0136] (3) Li, G.; Zhu, R.; Yang, Y. Polymer Solar Cells. Nat. Photonics 2012, 6 (3), 153-161. https://doi.org/10.1038/nphoton.2012.11. [0137] (4) Wang, G.; Melkonyan, F. S.; Facchetti, A.; Marks, T. J. All-Polymer Solar Cells: Recent Progress, Challenges, and Prospects. Angew. ChemieInt. Ed. 2019, 4129-4142. https://doi.org/10.1002/anie.201808976. [0138] (5) Yan, C.; Barlow, S.; Wang, Z.; Yan, H.; Jen, A. K.-Y.; Marder, S. R.; Zhan, X. Non-Fullerene Acceptors for Organic Solar Cells. Nat. Rev. Mater. 2018, 3 (3), 18003. https://doi.org/10.1038/natrevmats.2018.3. [0139] (6) Cui, Y.; Yao, H.; Zhang, J.; Xian, K.; Zhang, T.; Hong, L.; Wang, Y.; Xu, Y.; Ma, K.; An, C.; He, C.; Wei, Z.; Gao, F.; Hou, J. Single-Junction Organic Photovoltaic Cells with Approaching 18% Efficiency. Adv. Mater. 2020, 32 (19), 1908205. https://doi.org/10.1002/adma.201908205. [0140] (7) Liu, Q.; Jiang, Y.; Jin, K.; Qin, J.; Xu, J.; Li, W.; Xiong, J.; Liu, J.; Xiao, Z.; Sun, K.; Yang, S.; Zhang, X.; Ding, L. 18% Efficiency Organic Solar Cells. Sci. Bull. 2020, 65 (4), 272-275. https://doi.org/10.1016/j.scib.2020.01.001. [0141] (8) Liu, S.; Yuan, J.; Deng, W.; Luo, M.; Xie, Y.; Liang, Q.; Zou, Y.; He, Z.; Wu, H.; Cao, Y. High-Efficiency Organic Solar Cells with Low Non-Radiative Recombination Loss and Low Energetic Disorder. Nat. Photonics 2020, 14 (5), 300-305. https://doi.org/10.1038/s41566-019-0573-5. [0142] (9) Xu, X.; Feng, K.; Lee, Y. W.; Woo, H. Y.; Zhang, G.; Peng, Q. Subtle Polymer Donor and Molecular Acceptor Design Enable Efficient Polymer Solar Cells with a Very Small Energy Loss. Adv. Funct. Mater. 2020, 1907570, 1-9. https://doi.org/10.1002/adfm.201907570. [0143] (10) Zhou, Z.; Liu, W.; Zhou, G.; Zhang, M.; Qian, D.; Zhang, J.; Chen, S.; Xu, S.; Yang, C.; Gao, F.; Zhu, H.; Liu, F.; Zhu, X. Subtle Molecular Tailoring Induces Significant Morphology Optimization Enabling over 16% Efficiency Organic Solar Cells with Efficient Charge Generation. Adv. Mater. 2020, 32 (4), 1-8. https://doi.org/10.1002/adma.201906324. [0144] (11) Fan, B.; Zeng, Z.; Zhong, W.; Ying, L.; Zhang, D.; Li, M.; Peng, F.; Li, N.; Huang, F.; Cao, Y. Optimizing Microstructure Morphology and Reducing Electronic Losses in 1 Cm2 Polymer Solar Cells to Achieve Efficiency over 15%. ACS Energy Lett. 2019, 4 (10), 2466-2472. https://doi.org/10.1021/acsenergylett.9b01447. [0145] (12) Yan, T.; Song, W.; Huang, J.; Peng, R.; Huang, L.; Ge, Z. 16.67% Rigid and 14.06% Flexible Organic Solar Cells Enabled by Ternary Heterojunction Strategy. Adv. Mater. 2019, 31 (39), 1902210. https://doi.org/https://doi.org/10.1002/adma.201902210. [0146] (13) Kniepert, J.; Paulke, A.; Perdig?n-Toro, L.; Kurpiers, J.; Zhang, H.; Gao, F.; Yuan, J.; Zou, Y.; Le Corre, V. M.; Koster, L. J. A.; Neher, D. Reliability of Charge Carrier Recombination Data Determined with Charge Extraction Methods. J. Appl. Phys. 2019, 126 (20), 205501. https://doi.org/10.1063/1.5129037. [0147] (14) Zhao, W.; Li, S.; Yao, H.; Zhang, S.; Zhang, Y.; Yang, B.; Hou, J. Molecular Optimization Enables over 13% Efficiency in Organic Solar Cells. J. Am. Chem. Soc. 2017, 139 (21), 7148-7151. https://doi.org/10.1021/jacs.7b02677. [0148] (15) Yuan, J.; Zhang, Y.; Zhou, L.; Zhang, G.; Yip, H. L.; Lau, T. K.; Lu, X.; Zhu, C.; Peng, H.; Johnson, P. A.; Leclerc, M.; Cao, Y.; Ulanski, J.; Li, Y.; Zou, Y. Single-Junction Organic Solar Cell with over 15% Efficiency Using Fused-Ring Acceptor with Electron-Deficient Core. Joule 2019, 3 (4), 1140-1151. https://doi.org/10.1016/j.joule.2019.01.004. [0149] (16) Yuan, J.; Zhang, Y.; Zhou, L.; Zhang, C.; Lau, T.; Zhang, G.; Lu, X.; Yip, H.; So, S. K.; Beaupr?, S.; Mainville, M.; Johnson, P. A.; Leclerc, M.; Chen, H.; Peng, H.; Li, Y.; Zou, Y. Fused Benzothiadiazole: A Building Block for N-Type Organic Acceptor to Achieve High-Performance Organic Solar Cells. Adv. Mater. 2019, 31 (17), 1807577. https://doi.org/10.1002/adma.201807577. [0150] (17) Yoo, J. J.; Seo, G.; Chua, M. R.; Park, T. G.; Lu, Y.; Rotermund, F.; Kim, Y. K.; Moon, C. S.; Jeon, N. J.; Correa-Baena, J. P.; et al. Efficient Perovskite Solar Cells via Improved Carrier Management. Nature 2021, 590 (7847), 587-593. https://doi.org/10.1038/s41586-021-03285-w. [0151] (18) Vandewal, K.; Tvingstedt, K.; Gadisa, A.; Ingan?s, O.; Manca, J. V. On the Origin of the Open-Circuit Voltage of Polymer-Fullerene Solar Cells. Nat. Mater. 2009, 8 (11), 904-909. https://doi.org/10.1038/nmat2548. [0152] (19) Elumalai, N. K.; Uddin, A. Open Circuit Voltage of Organic Solar Cells: An in-Depth Review. Energy Environ. Sci. 2016, 9 (2), 391-410. https://doi.org/10.1039/C5EE02871J. [0153] (20) Bakulin, A. A.; Rao, A.; Pavelyev, V. G.; van Loosdrecht, P. H. M.; Pshenichnikov, M. S.; Niedzialek, D.; Cornil, J.; Beljonne, D.; Friend, R. H. The Role of Driving Energy and Delocalized States for Charge Separation in Organic Semiconductors. Science (80-.). 2012, 335 (6074), 1340-1344. https://doi.org/10.1126/science.1217745. [0154] (21) Yao, J.; Kirchartz, T.; Vezie, M. S.; Faist, M. A.; Gong, W.; He, Z.; Wu, H.; Troughton, J.; Watson, T.; Bryant, D.; et al. Quantifying Losses in Open-Circuit Voltage in Solution-Processable Solar Cells. Phys. Rev. Appl. 2015, 4 (1), 14020. https://doi.org/10.1103/PhysRevApplied.4.014020. [0155] (22) Qian, D.; Zheng, Z.; Yao, H.; Tress, W.; Hopper, T. R.; Chen, S.; Li, S.; Liu, J.; Chen, S.; Zhang, J.; et al. Design Rules for Minimizing Voltage Losses in High-Efficiency Organic Solar Cells. Nat. Mater. 2018, 17 (8), 703-709. https://doi.org/10.1038/s41563-018-0128-z. [0156] (23) Liu, J.; Chen, S.; Qian, D.; Gautam, B.; Yang, G.; Zhao, J.; Bergqvist, J.; Zhang, F.; Ma, W.; Ade, H.; et al. Fast Charge Separation in a Non-Fullerene Organic Solar Cell with a Small Driving Force. Nat. Energy 2016, 1 (7), 16089. https://doi.org/10.1038/nenergy.2016.89. [0157] (24) Lee, H. K. H.; Wu, J.; Barb?, J.; Jain, S. M.; Wood, S.; Speller, E. M.; Li, Z.; Castro, F. A.; Durrant, J. R.; Tsoi, W. C. Organic Photovoltaic Cells-Promising Indoor Light Harvesters for Self-Sustainable Electronics. J. Mater. Chem. A 2018, 6 (14), 5618-5626. https://doi.org/10.1039/c7ta10875c. [0158] (25) Mathews, I.; Kantareddy, S. N.; Buonassisi, T.; Peters, I. M. Technology and Market Perspective for Indoor Photovoltaic Cells. Joule 2019, 3 (6), 1415-1426. https://doi.org/10.1016/j.joule.2019.03.026. [0159] (26) Chen, F. C. Emerging Organic and Organic/Inorganic Hybrid Photovoltaic Devices for Specialty Applications: Low-Level-Lighting Energy Conversion and Biomedical Treatment. Adv. Opt. Mater. 2019, 7 (1), 1-24. https://doi.org/10.1002/adom.201800662. [0160] (27) Ma, L. K.; Chen, Y.; Chow, P. C. Y.; Zhang, G.; Huang, J.; Ma, C.; Zhang, J.; Yin, H.; Hong Cheung, A. M.; Wong, K. S.; So, S. K.; Yan, H. High-Efficiency Indoor Organic Photovoltaics with a Band-Aligned Interlayer. Joule 2020, 4 (7), 1486-1500. https://doi.org/10.1016/j.joule.2020.05.010. [0161] (28) Fan, B.; Du, X.; Liu, F.; Zhong, W.; Ying, L.; Xie, R.; Tang, X.; An, K.; Xin, J.; Li, N.; Ma, W.; Brabec, C. J.; Huang, F.; Cao, Y. Fine-Tuning of the Chemical Structure of Photoactive Materials for Highly Efficient Organic Photovoltaics. Nat. Energy 2018, 3 (12), 1051-1058. https://doi.org/10.1038/s41560-018-0263-4. [0162] (29) Zhao, J.; Li, Y.; Yang, G.; Jiang, K.; Lin, H.; Ade, H.; Ma, W.; Yan, H. Efficient Organic Solar Cells Processed from Hydrocarbon Solvents. Nat. Energy 2016, 1 (2), 15027. https://doi.org/10.1038/nenergy.2015.27. [0163] (30) Ma, L.-K.; Chen, Y.; Chow, P. C. Y.; Zhang, G.; Huang, J.; Ma, C.; Zhang, J.; Yin, H.; Hong Cheung, A. M.; Wong, K. S.; So, S. K.; Yan, H. High-Efficiency Indoor Organic Photovoltaics with a Band-Aligned Interlayer. Joule 2020, 4 (7), 1486-1500. https://doi.org/https://doi.org/10.1016/j.joule.2020.05.010. [0164] (31) Minnaert, B.; Veelaert, P. Efficiency Simulations of Thin Film Chalcogenide Photovoltaic Cells for Different Indoor Lighting Conditions. Thin Solid Films 2011, 519 (21), 7537-7540. https://doi.org/https://doi.org/10.1016/j.tsf.2011.01.362. [0165] (32) Freitag, M.; Teuscher, J.; Saygili, Y.; Zhang, X.; Giordano, F.; Liska, P.; Hua, J.; Zakeeruddin, S. M.; Moser, J.-E.; Grstzel, M.; Hagfeldt, A. Dye-Sensitized Solar Cells for Efficient Power Generation under Ambient Lighting. Nat. Photonics 2017, 11 (6), 372-378. https://doi.org/10.1038/nphoton.2017.60. [0166] (33) Cui, Y.; Wang, Y.; Bergqvist, J.; Yao, H.; Xu, Y.; Gao, B.; Yang, C.; Zhang, S.; Ingan?s, O.; Gao, F.; Hou, J. Wide-Gap Non-Fullerene Acceptor Enabling High-Performance Organic Photovoltaic Cells for Indoor Applications. Nat. Energy 2019, 4 (9), 768-775. https://doi.org/10.1038/s41560-019-0448-5. [0167] (34) Bai, F.; Zhang, J.; Zeng, A.; Zhao, H.; Duan, K.; Yu, H.; Cheng, K.; Chai, G.; Chen, Y.; Liang, J.; Ma, W.; Yan, H. A Highly Crystalline Non-Fullerene Acceptor Enabling Efficient Indoor Organic Photovoltaics with High EQE and Fill Factor. Joule 2021, 5 (5), 1231-1245. https://doi.org/10.1016/j.joule.2021.03.020.
[0168] All publications, patents and patent applications mentioned in this Specification are indicative of the level of skill of those skilled in the art to which this invention pertains and are herein incorporated by reference to the same extent as if each individual publication, patent, or patent applications was specifically and individually indicated to be incorporated by reference.
[0169] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.