KR20210073462A - Compound containing aryloxy akyl group and organic electronic device using them - Google Patents

Abstract

The present invention relates to a novel compound and an organic electronic device using the same. More specifically, the present invention relates to a novel non-fullerene-based acceptor in which an alkyl group substituted with aryloxy or heteroaryloxy is introduced into a central electron donor unit, and an organic solar cell including the same.

Description

(Aryloxy) alkyl group-substituted compound and organic electronic device using the same {Compound containing aryloxy akyl group and organic electronic device using them}

The present invention relates to a novel compound and an organic electronic device using the same, wherein the compound of the present invention is a compound in which at least one (aryloxy)alkyl group is substituted.

Representative examples of the organic electronic device include an organic light emitting device (OLED), an organic thin film transistor (OTFT), an organic photosensor (OPD), an organic solar cell (OPV), a photodetector, a memory device, and a logic circuit.

The double organic solar cell uses an electron donor and an electron acceptor as the photoactive layer at the same time. Compared to the conventional inorganic semiconductor device, the film formation conditions are not difficult, and the thickness of within several hundred nm and the relatively inexpensive photoactivity are not difficult. Due to the advantage of being able to fabricate a material of a layer, particularly a flexible device that can be bent at will, a lot of research is being conducted in recent years.

Specifically, an organic solar cell consists of a junction structure of an electron donor and an electron acceptor, and is a very fast charge transfer phenomenon called "photoinduced charge transfer (PICT)" between the electron donor and the electron acceptor, Research is being conducted to obtain a highly efficient organic solar cell by increasing the photoexcitation charge transfer phenomenon.

Compounds used as electron donors for organic solar cells are currently being studied a lot, focusing on p-type conductive polymers. For example, poly para-phenylenevinylene (hereinafter referred to as "PPV") series In addition to the high molecular compounds of , polythiophene (hereinafter, referred to as "PT"), various derivatives focusing on low bandgap polymers have been used recently.

Also, as an electron acceptor for organic solar cells, PCBM ({6}-1-(3-(methoxycarbonyl)propyl)-{ 5}-1-phenyl[5,6]C61({6}-1-(3-(methoxycarbonyl)propyl)-{5}-1-phenyl[5,6]C61)), and other As a single molecule, perylene, 3,4,9,10-perylenetetracarboxylic acid diimide, phthalocyanine, pentacene, and the like are used. However, many fullerene derivatives as well as fullerene derivatives represented by PCBM have low solubility in organic solvents, so when mixed with a polymer compound used as an electron donor, phase separation occurs or the overall efficiency is low in appearance. have. Moreover, the absorption of sunlight is weak and the energy level manipulation is difficult.

Since many fullerene derivatives have low solubility in organic solvents, a phase separation phenomenon occurs when mixed with a polymer, and there is a problem that the overall efficiency is low in appearance, and the light absorption is weak in the strong region of the solar spectrum and energy It is difficult to operate by classification, and the miscibility with the electron donor as described above is low, so there is an urgent need for research on a compound to replace fullerene.

However, studies on electron donors centered on low bandgap polymers have been conducted in various ways to date, whereas studies on compounds that can replace fullerene derivatives used as electron acceptors have hardly been conducted.

Specifically, it is a compound that can replace fullerene derivatives. It has excellent solubility in organic solvents, high electron affinity similar to fullerene, and excellent compatibility with electron donors, high absorption coefficient for sunlight, and excellent photoelectric conversion efficiency. Research on the compound is needed.

Joule, Volume 3, Issue 4, 17 April 2019, Pages 1140-1151

In order to solve the above problems, an object of the present invention is to provide a novel compound having an extended conjugated structure and maximizing charge transfer in a molecule by enabling intermolecular stacking.

An object of the present invention is to provide an organic electronic device having excellent light efficiency by employing the compound of the present invention.

An object of the present invention is to provide an organic solar cell having excellent photoelectric conversion efficiency by employing the compound of the present invention in a photoactive layer.

For the above purpose, the present invention may comprise the following means.

The compound according to an embodiment of the present invention is a small molecule compound of ADA consisting of a central electron donor unit (D) and a terminal electron acceptor unit (A) on both sides of the central electron donor unit (D). It has a skeleton, forms a delocalized pi-electron system along the central skeleton, and has a structure in which charge mobility is maximized due to a structure in which a substituent of a specific structure is introduced into the central electron donor unit, may be displayed as

[Formula 1]

[In Formula 1,

L ₁ and L ₂ are each independently C1-C30 alkylene;

W ₁ and W ₂ are each independently O or S;

Ar ₁ and Ar ₂ are each independently C6-C30 aryl or C3-C30 heteroaryl;

U ₁ is NR′ or S;

R' is C1-C30 alkyl;

R ₁ and R ₂ are each independently C1-C30 alkyl;

로 대체될 수 있으며, 상기 R은 수소, C1-C30알킬, C1-C30알콕시, C1-C30알킬티오, 할로겐, 시아노, 니트로, 히드록시, 할로C1-C30알킬, C1-C30알킬카보닐 또는 C1-C30알킬카보닐옥시이고;V ₁ and V ₂ are each independently a fused ring having methylidene as a linking group, and the fused rings are each independently C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1- It may be further substituted with one or more substituents selected from C30 alkyl, nitro and hydroxy, and -CH ₂ - of the fused ring is carbonyl, thiocarbonyl or

wherein R is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy, haloC1-C30 alkyl, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;

X ₁ to X ₄ are each independently O, S or Se;

The heteroaryl includes one or more heteroatoms selected from N, O, S and Se.]

In the compound according to an embodiment, in Formula 1, the fused rings (V ₁ and V ₂ ) having the methylidene as a linking group may be each independently represented by Formula A below.

[Formula A]

[In Formula A,

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

A is a C6-C20 aromatic ring or a C3-C20 heteroaromatic ring, wherein the aromatic ring and the heteroaromatic ring are C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1-C30 alkyl , may be further substituted with one or more substituents selected from nitro and hydroxy.]

In the compound according to an embodiment, in Formula 1, the fused rings (V ₁ and V ₂ ) having the methylidene as a linking group may be each independently represented by Formula B or Formula C below.

[Formula B]

[Formula C]

[In the above formulas B and C,

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;

R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;

Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl or an adjacent substituent It may be connected with R ₁₃ or R ₁₄ to form an aromatic fused ring;

R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.]

In the compound according to an embodiment, in Formula 1, the fused rings (V ₁ and V ₂ ) having the methylidene as a linking group may be each independently represented by Formulas D to G below.

[Formula D]

[Formula E]

[Formula F]

[Formula G]

[In the above formulas D to G,

Y ₁ and Y ₂ are each independently O or S;

R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;

R ₂₁ to R ₂₇ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano or haloC1-C30 alkyl.]

The compound according to an embodiment may be represented by the following Chemical Formula 2.

[Formula 2]

[In Formula 2, X ₁ to X ₄ , L ₁ , L ₂ , Ar ₁ , Ar ₂ , U ₁ , R ₁ and R ₂ are the same as defined in Formula 1;

V ₁ and V ₂ are each independently represented by Formula B or Formula C;

[Formula B]

[Formula C]

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;

R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;

Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl, or an adjacent substituent may be connected to R ₁₃ or R ₁₄ to form an aromatic fused ring;

R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.]

The compound according to an embodiment may be represented by the following Chemical Formulas 3 to 6.

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[In Formulas 3 to 6,

X ₁ to X ₄ are each independently O, S or Se;

U ₁ is NR′ or S;

R' is C1-C30 alkyl;

R ₁ and R ₂ are each independently C1-C30 alkyl;

Q ₁ to Q ₆ are each independently CH or N;

R ₃₁ to R ₃₅ are each independently C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano or haloC1-C30 alkyl;

m and n are each independently an integer from 0 to 2;

x and y are each independently an integer from 1 to 30.]

In addition, the present invention provides an organic electronic device including the compound according to an embodiment.

The organic electronic device according to an embodiment may be an organic light emitting device, an organic thin film transistor, an organic photosensor, or an organic solar cell, preferably an organic solar cell.

In the organic electronic device according to an embodiment, the compound may be included in the photoactive layer of the organic solar cell.

In the organic electronic device according to an embodiment, the compound may be included in the photoactive layer of the organic solar cell as an electron acceptor.

The compounds of the present invention are Due to the introduction of an alkyl group substituted with aryloxy or heteroaryloxy at the nitrogen atom of pyrrole in the central electron donor unit, it has excellent chemical and thermal stability as well as improved crystallinity, enabling intermolecular stacking.

In addition, since the compound of the present invention can implement improved charge mobility due to higher crystallinity, the photoelectric conversion efficiency of an organic solar cell device employing the same can be improved.

In addition, the compound of the present invention has high compatibility with known electron donors, and can increase the energy conversion efficiency of an organic electronic device including the same.

Furthermore, the organic electronic device employing the compound of the present invention as an electron acceptor lowers the driving voltage, improves the light efficiency, can improve the lifespan characteristics of the device by the thermal stability of the compound, and has excellent durability over a long period of time.

In addition, the compound of the present invention can be manufactured with high purity and high yield by a simple process with a single molecule, and thus has very high industrial application potential.

With these characteristics, the compound of the present invention can be used as a compound that can replace the fullerene derivative widely used as an electron acceptor, thereby improving the characteristics of an organic solar cell. That is, the compound of the present invention is highly applicable as a non-fullerene-based electron acceptor.

1 is a UV-vis absorption spectrum of the solution phase and film phase of Compound 1 prepared in Example 1. FIG.
2 is a UV-vis absorption spectrum of the solution phase and film phase of Compound 2 prepared in Example 2.
3 shows the structures of electron donors PBDT-H and PBDT.

The novel compound according to the present invention and an organic electronic device using the same will be described in detail below, but unless there are other definitions in the technical and scientific terms used at this time, those of ordinary skill in the art to which this invention pertains will generally understand Descriptions of well-known functions and configurations that may unnecessarily obscure the gist of the present invention in the following description will be omitted.

Throughout this specification, unless the context requires otherwise, references to "comprises" and "comprising" include, but are not limited to, a given step or element, or group of steps or elements, but any other step or element, or It is to be understood that a step or group of elements is not excluded.

As used herein, the terms “substituent”, “radical”, “group”, “moiety”, and “fragment” may be used interchangeably.

As used herein, the term "C _A -C _B " means "the number of carbon atoms is A or more and B or less".

As used herein, the term “alkyl” refers to a monovalent straight-chain or branched saturated hydrocarbon radical composed only of carbon and hydrogen atoms. The alkyl includes, but is not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl, ethylhexyl, heptyl, octyl, nonyl, decyl, dodecyl, undecyl, and the like. .

As used herein, the term "aryl" is an aromatic ring monovalent organic radical derived from an aromatic hydrocarbon by removal of one hydrogen, suitably containing 4 to 7, preferably 5 or 6 ring atoms in each ring. It includes a single or fused ring system, and includes a form in which a plurality of aryls are connected by a single bond. Specific examples include, but are not limited to, phenyl, naphthyl, biphenyl, anthryl, indenyl, fluorenyl, and the like.

As used herein, the term "heteroaryl" refers to an aryl group containing 1 to 4 heteroatoms selected from N, O, S and Se as aromatic ring skeleton atoms, and the remaining aromatic ring skeleton atoms are carbon, and 5 to 6-membered monocyclic heteroaryl, and polycyclic heteroaryl condensed with one or more benzene rings. In addition, heteroaryl in the present invention includes a form in which one or more heteroaryls are connected by a single bond. Specific examples include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, isoxazolyl, oxazolyl, monocyclic heteroaryl such as pyridyl, benzofuranyl, dibenzofuranyl, di Polycyclic heterocycles such as benzothiophenyl, benzothiophenyl, isobenzofuranyl, benzoimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, quinolyl, isoquinolyl, and carbazolyl aryl and the like.

As used herein, the term "alkoxy" refers to an -O-alkyl radical, where 'alkyl' is as defined above. Specific examples include, but are not limited to, methoxy, ethoxy, isopropoxy, butoxy, isobutoxy, t-butoxy, and the like.

As used herein, the term "alkylthio" refers to an -S-alkyl radical, where 'alkyl' is as defined above. Specific examples include, but are not limited to, methylthio, ethylthio, isopropylthio, butylthio, isobutylthio, t-butylthio, and the like.

As used herein, the term “halo” or “halogen” refers to a halogen element and includes, for example, fluoro, chloro, bromo and iodo.

As used herein, the term "cyano" refers to -CN, "nitro" refers to -NO ₂ , and "hydroxy" refers to -OH.

As used herein, the term "haloalkyl" refers to an alkyl radical in which one or more hydrogen atoms are each replaced with a halogen atom, where 'alkyl' and 'halogen' are as defined above. For example, haloalkyl can include fluoromethyl, difluoromethyl, trifluoromethyl, fluoroethyl, difluoroethyl, perfluoroethyl, bromomethyl, bromoethyl, bromopropyl, and the like. have.

As used herein, the term "carbonyl" means a divalent organic radical represented by *-C(=O)-*, and "thiocarbonyl" is a divalent organic radical represented by *-C(=S)-*. organic radicals.

As used herein, the term "alkylcarbonyl" refers to a -C(=O)alkyl radical, where 'alkyl' is as defined above. Examples of such alkylcarbonyl radicals include, but are not limited to, methylcarbonyl, ethylcarbonyl, isopropylcarbonyl, propylcarbonyl, butylcarbonyl, isobutylcarbonyl, t-butylcarbonyl, and the like.

As used herein, the term "alkylcarbonyloxy" refers to an -OC(=O)alkyl radical, where 'alkyl' is as defined above. Examples of such alkylcarbonyloxy radicals include methylcarbonyloxy, ethylcarbonyloxy, isopropylcarbonyloxy, propylcarbonyloxy, butylcarbonyloxy, isobutylcarbonyloxy, t-butylcarbonyloxy, and the like. However, the present invention is not limited thereto.

As used herein, the term “alkylene” refers to a divalent straight-chain or branched saturated hydrocarbon radical composed only of carbon and hydrogen atoms. Examples of such alkylenes include, but are not limited to, methylene, ethylene, propylene, isopropylene, butylene, isobutylene, t-butylene, pentylene, hexylene, heptylene, octylene, nonylene, and the like. .

The compound according to an embodiment of the present invention is a small molecule compound of ADA consisting of a central electron donor unit (D) and a terminal electron acceptor unit (A) on both sides of the central electron donor unit (D). To provide a compound having a structure that has a skeleton, forms a delocalized pi-electron system along the central skeleton, and maximizes charge mobility due to a structure in which a substituent of a specific structure is introduced into the central electron donor unit. , The compound of the present invention is represented by the following formula (1).

[Formula 1]

[In Formula 1,

L ₁ and L ₂ are each independently C1-C30 alkylene;

W ₁ and W ₂ are each independently O or S;

Ar ₁ and Ar ₂ are each independently C6-C30 aryl or C3-C30 heteroaryl;

U ₁ is NR′ or S;

R' is C1-C30 alkyl;

R ₁ and R ₂ are each independently C1-C30 alkyl;

로 대체될 수 있으며, 상기 R은 수소, C1-C30알킬, C1-C30알콕시, C1-C30알킬티오, 할로겐, 시아노, 니트로, 히드록시, 할로C1-C30알킬, C1-C30알킬카보닐 또는 C1-C30알킬카보닐옥시이고;V ₁ and V ₂ are each independently a fused ring having methylidene as a linking group, and the fused rings are each independently C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1- It may be further substituted with one or more substituents selected from C30 alkyl, nitro and hydroxy, and -CH ₂ - of the fused ring is carbonyl, thiocarbonyl or

wherein R is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy, haloC1-C30 alkyl, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;

X ₁ to X ₄ are each independently O, S or Se;

The heteroaryl includes one or more heteroatoms selected from N, O, S and Se.]

The compound of the present invention has a structure in which a substituent of a specific structure is introduced into the central electron donor unit, that is, maximized charge mobility due to the introduction of an alkyl group substituted with aryloxy or heteroaryloxy to the nitrogen atom of pyrrole in the central electron donor unit. and has high chemical and electrical stability, high thermal stability and excellent durability, and can exhibit excellent solar cell efficiency.

In addition, the compound of the present invention has a high absorption coefficient for sunlight, a high charge mobility, and can improve thermal stability and electrical properties of an organic electronic device including the same.

In addition, the compound of the present invention has excellent solubility in organic solvents and has excellent miscibility with known electron donors, so that the efficiency of organic electronic devices including the same, particularly organic solar cells, can be increased. Furthermore, by employing the compound of the present invention as a non-fullerene-based electron acceptor of an organic solar cell, a lowered driving voltage and improved photoelectric conversion efficiency can be realized, and the lifespan characteristics of the device can be improved by the thermal stability of the compound.

The compound of the present invention has a structure in which a fused ring having methylidene as a linking group is introduced, specifically, a fused ring having methylidene as a linking group in order to further improve intermolecular interaction by forming a conjugate extended outside the central skeleton (V ₁ and V ₂ ) may be each independently represented by Formula A below.

[Formula A]

[In Formula A,

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

A is a C6-C20 aromatic ring or a C3-C20 heteroaromatic ring, wherein the aromatic ring and the heteroaromatic ring are C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1-C30 alkyl , may be further substituted with one or more substituents selected from nitro and hydroxy.]

More specifically, the fused rings (V ₁ and V ₂ ) having methylidene as a linking group may be each independently represented by the following Chemical Formula B or Chemical Formula C.

[Formula B]

[Formula C]

[In the above formulas B and C,

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;

R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;

Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl or an adjacent substituent It may be connected with R ₁₃ or R ₁₄ to form an aromatic fused ring;

R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.]

More preferably, the fused rings (V ₁ and V ₂ ) having the methylidene as a linking group may each independently be represented by the following Chemical Formula D, Chemical Formula E, Chemical Formula F, or Chemical Formula G, and even more preferably, Chemical Formula D Or it may be one represented by Formula E.

[Formula D]

[Formula E]

[Formula F]

[Formula G]

[In the above formulas D to G,

Y ₁ and Y ₂ are each independently O or S;

R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;

R ₂₁ to R ₂₇ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano or haloC1-C30 alkyl.]

In one embodiment, the aromatic rings (V ₁ and V ₂ ) having methylidene as a linking group may be selected from the following structures, but are not limited thereto.

The compound of the present invention minimizes quenching of the excited state by the vibronic path due to the above-described structural features, thereby achieving a higher absorption coefficient for sunlight due to less energy loss due to absorption of sunlight. In addition, the compound has high crystallinity, so that it is possible to realize high charge mobility.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be the same as each other.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be all S, U ₁ may be NR′, and R′ may be C1-C30 alkyl.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be all S, and U ₁ may be S.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may all be Se, U ₁ may be NR′, and R′ may be C1-C30 alkyl.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be all Se, and U ₁ may be S.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be all O, U ₁ may be NR′, and R′ may be C1-C30 alkyl.

In the compound according to an embodiment, in Formula 1, X ₁ to X ₄ may be all O, and U ₁ may be S.

In the compound according to an embodiment, in Formula 1, X ₁ and X ₄ may be the same as each other, and X ₂ and X ₃ may be the same as each other.

In the compound according to an embodiment, in Formula 1, X ₁ and X ₄ may be S, X ₂ and X ₃ may be Se, U ₁ may be NR′, and R′ may be C1-C30 alkyl.

In the compound according to an embodiment, in Formula 1, X ₁ and X ₄ may be S, X ₂ and X ₃ may be Se, and U ₁ may be S.

In the compound according to an embodiment, in Formula 1, X ₁ and X ₄ may be Se, X ₂ and X ₃ may be S, U ₁ may be NR′, and R′ may be C1-C30 alkyl.

In the compound according to an embodiment, in Formula 1, X ₁ and X ₄ may be Se, X ₂ and X ₃ may be S, and U ₁ may be S.

In the compound according to an embodiment, more bring an improved ball myeonseong strong intermolecular π-π stacking - preferably to the side for implementing the (π π stacking) can be represented by the following formula (2).

[Formula 2]

[In Formula 2, X ₁ to X ₄ , L ₁ , L ₂ , Ar ₁ , Ar ₂ , U ₁ , R ₁ and R ₂ are the same as defined in Formula 1;

V ₁ and V ₂ are each independently represented by Formula B or Formula C;

[Formula B]

[Formula C]

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;

one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;

R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;

Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl or an adjacent substituent It may be connected with R ₁₃ or R ₁₄ to form an aromatic fused ring;

R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.]

For example, in Formula B or Formula C, Y ₁ is O; Y ₂ is C(CN) ₂ ; Z ₁ is CR ₁₈ ; R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy or halogen; one of Z ₂ and Z ₃ is CR ₁₇ and the other is S; R ₁₇ is hydrogen or C 1 -C 30 alkyl; R ₁₃ to R ₁₅ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy or halogen; R ₁₆ may be hydrogen or C1-C30 alkyl.

For example, Ar ₁ and Ar ₂ may each independently be C6-C20 aryl or C3-C20 heteroaryl, preferably C6-C20 aryl, more preferably C6-C12 aryl.

In one embodiment, Ar ₁ and Ar ₂ may each independently be a monovalent group selected from the following structures.

In terms of improving solubility, it is preferable that at least one long-chain alkyl is substituted in the central electron donor unit (D). That is, _{at least one of R 1} and R ₂ is a long-chain alkyl. For example, in terms of improving solubility _{, at least one of R 1} and R ₂ may be C7-C30 alkyl.

In the compound according to an embodiment, it may be more preferably represented by the following Chemical Formulas 3 to 6 in terms of realizing improved photoelectric conversion efficiency due to maximized charge mobility.

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[In Formulas 3 to 6,

X ₁ to X ₄ are each independently O, S or Se;

U ₁ is NR′ or S;

R' is C1-C30 alkyl;

R ₁ and R ₂ are each independently C1-C30 alkyl;

Q ₁ to Q ₆ are each independently CH or N;

R ₃₁ and R ₃₂ are each independently C1-C30 alkyl, C1-C30 alkoxy or halogen;

R ₃₃ to R ₃₅ are each independently hydrogen or C1-C30 alkyl;

m and n are each independently an integer from 0 to 2;

x and y are each independently an integer from 1 to 30.]

In the compounds of Formulas 3 to 6 according to an embodiment, X ₁ to X ₄ are each independently S; U ₁ is S; R ₁ and R ₂ are each independently C7-C30 alkyl; Q ₁ to Q ₆ are each independently CH; R ₃₁ and R ₃₂ are each independently C1-C10 alkyl, C1-C10 alkoxy or halogen; R ₃₃ to R ₃₅ are each independently hydrogen or C 1 -C 10 alkyl; m and n are each independently an integer from 0 to 2; x and y may each independently be an integer from 5 to 30.

In one embodiment, the compound may be selected from the following structures, but is not limited thereto.

The compound according to an embodiment may be included in an organic electronic device, and among them, it is used as an electron acceptor material in the photoactive layer of an organic solar cell to replace the fullerene derivative used in the prior art It is possible to improve the photoelectric conversion efficiency in the organic solar cell Do.

Of course, the compound according to an embodiment can be prepared through a conventional organic synthesis method, and the organic solvent used is not limited, and the reaction time and temperature are also changeable within the range that does not deviate from the essence of the invention. Of course.

The present invention also provides an organic electronic device comprising the compound described above.

The organic electronic device according to an embodiment is not limited as long as it is a device in which the compound of the present invention can be used, and as a non-limiting example thereof, the organic electronic device includes an organic solar cell, an organic thin film transistor, an organic memory, or an organophotoreceptor, an organic electronic device. and an optical sensor, preferably an organic solar cell or an organic thin film transistor, and more preferably an organic solar cell.

The organic electronic device according to an embodiment is an organic solar cell, and the compound may be included in a photoactive layer of the organic solar cell.

More specifically, the compound of the present invention is used as an electron acceptor as a substitute for a fullerene derivative conventionally used in an organic solar cell, and an organic solar cell employing the same has improved photoelectric conversion efficiency.

Hereinafter, a method for manufacturing an organic solar cell according to the present invention will be described with an example, but is not limited thereto.

The organic solar cell has a structure in which a hole transport layer and an electron transport layer are bonded, and when sunlight is absorbed, an electron-hole pair is generated in the hole acceptor, and electrons move to the electron acceptor to separate electron-holes. It shows the photoelectric conversion effect through the process.

Accordingly, the present invention confirmed that surprisingly improved photoelectric conversion efficiency can be achieved by employing the compound of the present invention in an organic solar cell. In addition, the compound of the present invention has high crystallinity and high charge mobility, so that it can be used as an electron acceptor material in the photoactive layer of an organic solar cell to realize high efficiency.

The organic solar cell according to an embodiment of the present invention may include a substrate, a first electrode, a photoactive layer and a second electrode, and may further include a hole transport layer, an electron transport layer, and the like.

Also, the organic solar cell according to an embodiment of the present invention may be an inverted type organic solar cell.

In addition to glass and quartz plate, the substrate is PET (polyethylene terephthalate), PEN (polyethylene naphthelate), PP (polyperopylene), PI (polyimide), PC (polycarbornate), PS (polystylene), POM (polyoxyethlene), AS resin (acrylonitrile styrene) copolymer), ABS resin (acrylonitrile butadiene styrene copolymer), and TAC (Triacetyl cellulose) may be made of a flexible and transparent material such as plastic.

In addition, the first electrode is formed by coating a transparent electrode material on one surface of the substrate or coating it in a film form using sputtering, E-Beam, thermal evaporation, spin coating, screen printing, inkjet printing, doctor blade or gravure printing method. do. The first electrode is a part functioning as an anode, and is a material having a greater work function compared to a second electrode to be described later, and any material having transparency and conductivity may be used. For example, indium tin oxide (ITO), gold, silver, fluorine doped tin oxide (FTO), aluminum doped zink oxide (AZO), indium zink oxide (IZO) ), ZnO-Ga ₂ O ₃ , ZnO-Al ₂ O ₃ and antimony tin oxide (ATO, SnO ₂ -Sb ₂ O ₃ ), etc., and preferably ITO.

The photoactive layer is composed of a mixture of an electron acceptor and an electron donor, and can provide a photovoltaic effect through very fast charge transfer and separation, and the compound of the present invention may be included as an electron acceptor, and its blending amount depends on the use. can be appropriately adjusted. In addition, the compound of the present invention may be dissolved in an organic solvent and used as an electron acceptor material of the photoactive layer to a thickness of 60 mm or more, preferably 60 to 120 nm. In addition, as an example of an electron donor, PBDB-T (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5) -b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c: 4',5'-c']dithiophene-4,8-dione))]), PBDB-TS (poly[(2,6-(4,8-bis(5-(2-ethylhexylthio)thiophen-2- yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis( 2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione))), PBDB-T-SF (Poly[(2,6-(4) ,8-bis(5-(2-ethylhexylthio)-4-fluorothiophen-2-yl)-benzo[1,2-b:4,5-b']-dithiophene))-alt-(5,5-( 1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione )]), PBDB-T-2F (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)-benzo[1,2-b:4 ,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'- c:4',5'-c']dithiophene-4,8-dione)]), PBDTTT-CT (poly[(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo [1,2-b;4,5-b']dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene))-2,6- diyl]), PBDTTT-CF (poly[1-(6-{ 4,8-bis[(2-ethylhexyl)oxy]-6-methylbenzo[1,2- b :4,5- b' ]dithiophen-2-yl}-3-fluoro-4-methylthieno[3,4- b ]thiophen-2-yl)-1-octanone]), J51 (Poly[(5,6-difluoro-2-octyl-2H-benzotriazole-4,7-diyl)-2,5-thiophenediyl[4,8 -bis[5-(2-hexyldecyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl]), PBDTT-DPP (poly{2,6'-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,4-b]dithiophene-alt-5-dibutyloctyl-3,6-bis(5-bromothiophen- 2-yl)pyrrolo[3,4-c]pyrrole-1,4-dione}, P3HT (poly(3-hexylthiophene)), PCDTBT (poly[N-9'-heptadecanyl-2,7-carbazole-alt- 5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)]), PBDT-H, PBDT-F, and the like. The electron donor and the compound of the present invention are mixed in a weight ratio of 1: 0.5 to 1: 4 and a solution dissolved in an organic solvent is used to form a photoactive layer by spin coating, spray coating, screen printing, doctor blade method, etc. have. The organic solvent is a single organic solvent or two or more organic solvents having different boiling points, specifically chlorobenzene, acetone, methanol, tetrahydrofuran, toluene, xylene, tetralin, 1,2-dichlorobenzene and chloroform. It may be one or more organic solvents selected from the group consisting of.

The photoactive layer according to an embodiment may further include an additional additive in order to realize excellently improved efficiency by controlling the morphology and crystallinity of the active layer. Examples of the additive include 1,8-diiodooctane (DIO: 1,8-diiodooctane), 1-chloronaphthalene (1-CN: 1-chloronaphthalene), diphenyl ether (DPE: diphenylether), octanedithiol (octane dithiol), tetrabromothiophene (tetrabromothiophene), and the like, and may be appropriately mixed according to the use.

In addition, the photoactive layer including the compound according to the present invention has a high electron density, and thus a short circuit current density and an open circuit voltage increase to improve the photoelectric conversion efficiency. That is, the compound according to the present invention is used as an electron acceptor and as a substitute for a fullerene derivative conventionally used in an organic solar cell, and an organic solar cell employing the same has improved photoelectric conversion efficiency.

In addition, the second electrode may be deposited using a thermal evaporator in a state in which the electron transport layer is introduced. In this case, usable electrode materials include lithium fluoride/aluminum, lithium fluoride/calcium/aluminum, aluminum/calcium, barium/aluminum fluoride, barium fluoride/barium/aluminum, barium/aluminum, aluminum, gold, silver, magnesium: silver and It may be selected from lithium:aluminum, and it is preferable to use an electrode made of silver, aluminum, aluminum/calcium or barium fluoride/barium/aluminum structure.

Also, the materials of the electron transport layer and the hole transport layer may be used differently from general types of electron transport layer and hole transport layer. An example of the electron transport material is TiO _x, ZnO, TiO _2, ZrO _2, MgO, HfO there may be mentioned _2, etc., an example of the hole transport layer material is NiO, Ta ₂ O _3, MoO _3, Ru ₂ O _3, etc. of metal oxides. In addition, it goes without saying that an organic conjugated polymer electrolyte having a cation or an anion in addition to the above-described metal oxide may be used as a material for the electron transport layer or the hole transport layer.

In addition, PDINN (2,9-bis(3-((3-(dimethylamino)propyl)amino)propyl)anthra[2,1,9-def:6, 5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone) may be further included.

Hereinafter, the present invention will be described in detail by way of Examples. However, the following examples are only for illustrating the present invention, and the content of the present invention is not limited by the following examples. At this time, unless there are other definitions in the technical terms and scientific terms used, those of ordinary skill in the art to which this invention belongs have the meanings commonly understood. In addition, repeated description of the same technical configuration and operation as in the prior art will be omitted.

[Example 1] Preparation of compound ThSeC ₁₁ Bz-IC

Step 1: Preparation of compound A

In a three-necked flask, 4,7-dibromo-5,6-dinitrobenzo [c] [1,2,5] thiadiazole (10 g, 26 mmol), tributyl (3-undecyl thieno [3 ,2-b]thiophen-5-yl)stannane (34.3g, 57.3 mmol) was dissolved in toluene (150 mL), and the catalyst Pd(PPh ₃ ) ₂ Cl ₂ (0.36 g, 0.52 mmol) was added thereto. Then, the temperature was raised to 90° C. and stirred under reflux for 12 hours. After lowering the temperature to room temperature, the solvent was removed under reduced pressure. The obtained solid was purified by recrystallization (Chloroform: Hex = 5 : 1) to obtain Compound A (13.7 g, 65%).

¹ H-NMR (300 MHz, CDCl ₃ ) δ (ppm) 7.71 (s, 2H), 7.18 (s, 2H), 2.78 (t, J = 7.6 Hz, 4H), 1.83-1.75 (m, 4H), 1.30 (d, J = 27.9 Hz, 32H), 0.88 (t, J = 6.8 Hz, 6H).

Step 2: 3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2'',3'':4',5']thieno[2' Preparation of ,3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole (Compound B)

In a three-necked flask, compound A (8.10 g, 10 mmol) and triethyl phosphate (50 mL) were dissolved in o-dichlorobenzene (20 mL) under a nitrogen atmosphere. After heating at 180° C. for more than 8 hours, the water layer was extracted with dichloromethane and the organic layer was dried over anhydrous Na ₂ SO ₄ and filtered. The next reaction was carried out without the need for further purification.

Step 3: 12,13-bis(6-phenoxyhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-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 (compound C) Preparation of

The crude compound B obtained in step 2 was added to a three-necked round bottom flask, ((6-bromohexyl)oxy)benzene (3.86 g, 15 mmol), KOH (4.90 g, 35.64 mmol) and DMF ( 80 mL) and then purged with argon for 15 minutes to remove oxygen. Then, the reaction mixture was refluxed at 80° C. for 15 hours and then filtered. After removing the solvent from the obtained filtrate, it was extracted with _{ethyl acetate and H 2 O.} The obtained organic layers were combined, dried over anhydrous MgSO ₄ , filtered, and the solvent was removed using a rotary evaporator. The obtained residue was purified by silica gel column chromatography (eluent: dichloromethane/petroleum ether = 1/10 (v/v)) to obtain Compound C as a red solid (4.95 g, 45 % yield).

¹ H NMR (300 MHz, CD ₂ Cl ₂ ) δ (ppm) 7.18-7.06(m, 2H), 6.95(s, 1H), 6.84-6.74(m, 1H), 6.72-6.63(m, 2H), 4.55 (t, J = 7.5 Hz, 2H), 3.67 (t, J = 6.4 Hz, 2H), 2.72 (t, J = 7.6 Hz, 2H), 1.90-1.65 (m, 4H), 1.59-1.40 (m) , 3H), 1.42-1.03 (m, 21H), 0.79 (t, J = 6.7 Hz, 3H).

Step 4: 12,13-bis(6-phenoxyhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-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 , Preparation of 10-dicarb aldehyde (Compound D)

Compound C (0.55 g, 0.50 mmol) was dissolved in THF (20 mL), and after lowering the temperature to -78°C, n-BuLi (0.69 mL, 1.6M in hexane) was slowly added dropwise under a nitrogen stream, and at the same temperature. After further stirring for 1.5 hours, the temperature was raised to 0° C. over 30 minutes. After cooling to -78°C, dried DMF (0.12 mL, 3.66 mmol) was added in one portion, and then the temperature was raised to room temperature and stirred for 8 hours. Then, distilled water was poured to complete the reaction. Extracted twice with dichloromethane, the organic layers were combined, and the combined organic layers were washed with water and brine, dried over anhydrous MgSO ₄ , and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (eluent: dichloromethane/petroleum ether = 1/1 (v/v)) to obtain Compound D as a red solid (0.38 g, 66 % yield).

¹ H-NMR (300 MHz, CD ₂ Cl ₂ ) δ (ppm) 10.09(s, 1H), 7.26(t, J = 7.7 Hz, 2H), 6.98-6.75(m, 3H), 4.58(s, 2H) ), 3.88 (t, J = 6.1 Hz, 2H), 3.02 (t, J = 7.1 Hz, 2H), 2.01 (s, 2H), 1.86 (s, 2H), 1.76-1.59 (m, 2H), 1.59 -1.05 (m, 20H), 0.90 (d, J = 6.4 Hz, 3H).

Step 5: 2,2'-((2Z,2'Z)-((12,13-bis(6-phenoxyhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo [3,4-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-2,10-diyl)bis(methanylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2, Preparation of 1-diylidene))dimalononitrile (Compound 1)

Compound D (0.17 g, 0.15 mmol), 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (0.23 g, 1 mmol), pyridine (1 mL) and chloroform (30 mL) were placed in a round bottom flask under a nitrogen atmosphere and stirred at 65° C. for more than 12 hours. After completion of stirring, the mixture was cooled to room temperature, and the reaction mixture was poured into methanol and filtered. The filtered solid was purified by silica gel column chromatography (eluent: dichloromethane/petroleum ether = 1/1 (v/v)) to obtain Compound 1 as a dark blue solid (0.20 g, 85 % yield).

¹ H-NMR (300 MHz, CD ₂ Cl ₂ ) δ (ppm) 8.28 (s, 1H), 8.17 (dd, J = 10.1, 6.6 Hz, 1H), 7.33 (t, J = 7.6 Hz, 1H), 7.13-6.95(m, 2H), 6.87-6.56(m, 3H), 4.46(s, 2H), 3.86(t, J = 6.4 Hz, 2H), 2.81-2.62(m, 2H), 2.09(s, 2H), 1.83 (d, J = 6.5 Hz, 2H), 1.63 (s, 6H), 1.46-1.11 (m, 18H), 0.80 (t, J = 6.7 Hz, 3H).

[Example 2] Preparation of compound 2

2-(5,6-dichloro-3-3 in place of 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile Compound 2 was prepared by reacting in the same manner as in Example 1, except that oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (1 mmol) was used (0.20 g). , 80%).

¹ H-NMR (300 MHz, CD ₂ Cl ₂ ) δ (ppm) 8.28 (s, 1H), 8.17 (dd, J = 10.1, 6.6 Hz, 1H), 7.33 (t, J = 7.6 Hz, 1H), 7.13-6.95(m, 2H), 6.87-6.56(m, 3H), 4.46(s, 2H), 3.86(t, J = 6.4 Hz, 2H), 2.81-2.62(m, 2H), 2.09(s, 2H), 1.83 (d, J = 6.5 Hz, 2H), 1.63 (s, 6H), 1.46-1.11 (m, 18H), 0.80 (t, J = 6.7 Hz, 3H).

[Example 3] Preparation of compound 3

2-(3-oxo-2,3-dihydro instead of 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile Compound 3 was prepared by reacting in the same manner as in Example 1, except that -1H-inden-1-ylidene) malononitrile (1 mmol) was used.

¹ H NMR (300 MHz, CDCl ₃ ) δ 8.48(s, 1H), 8.4(d, 1H), 7.67(d, 1H), 7.36(m, 3H), 7.26(m,1H), 6.81(m, 2H), 6.80-6.63 (m, 3H), 4.56 (t, J = 7.4 Hz, 2H), 3.96 (t, J = 6.3 Hz, 2H), 2.91 (t, J = 7.6 Hz, 2H), 2.15 ( m, 2H), 1.92 (dd, J = 14.4, 7.6 Hz, 2H), 1.62 (dd, J = 17.0, 9.3 Hz, 2H), 1.52-1.15 (m, 20H), 0.87 (t, J = 6.6 Hz) , 3H).

[Example 4] Preparation of compound 4

2-(5-methyl-3-oxo-2, in place of 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile; Compound 4 was prepared by reacting in the same manner as in Example 1, except that 3-dihydro-1H-inden-1-ylidene)malononitrile (1 mmol) was used.

¹ H NMR (300 MHz, CDCl ₃ ) δ 8.66(d, 0.7H), 8.51(d, 0.3H), 8.37-8.20(m, 1H), 7.63(dd, 0.7H), 7.48(s, 0.3H) ), 7.19-7.10(m, 2H), 6.91-6.73(m, 3H), 4.60(s, 2H), 3.95(m, 2H), 2.98(s, 2H), 2.39(d, 2H), 2.11( s, 2H), 1.86 (m, 2H), 1.81-1.56 (m, 6H), 1.48 (m, 2H), 1.26 (s, 14H), 0.86 (t, 3H).

[Example 5] Preparation of compound 5

2-(3-oxo-2,3-dihydro instead of 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile Compound 5 was prepared by reacting in the same manner as in Example 1, except that -1H-inden-1-ylidene) malononitrile (1 mmol) was used, and its structure was ^{confirmed through 1} H NMR. .

[Example 6] Preparation of compound 6

2-(1-methyl-6-oxo-5, in place of 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile; Compound 6 was prepared by reacting in the same manner as in Example 1, except that 6-dihydro-4H-cyclopenta[c]thiophen-4-ylidene)malononitrile (1 mmol) was used, Its structure was ^{confirmed through 1} H NMR.

The light absorption regions of the compounds 1 and 2 prepared in Examples 1 and 2 were _{measured in a solution state (solution: CHCl 3} ) and a film state, and the results are shown in FIGS. 1 and 2 , respectively.

The optical properties of Compounds 1 and 2 prepared in Examples 1 and 2 are shown in Table 1 below, and the band gap (E _{g ) was obtained at} the UV absorption wavelength of the film state.

Compound 1 (Example 1) Compound 2 (Example 2) UV-Sol. CHCl ₃
max. (nm) 731 744 UV-Film
max. (nm) rt. 785 805 100℃ 826 848 λ _edge (nm) 881 884 E _g (optical) (eV) 1.40 1.40 ε (molar extinction coefficient)
(mol ^-1 cm ^-1 L) 205900 185600

[Examples 7 and 8] Fabrication of organic solar cells

In order to evaluate the performance of the compound of the present invention for use as an electron acceptor for an organic solar cell, an organic solar cell was prepared as follows.

Immerse the glass substrate coated with ITO (Indium Tin Oxide) as the anode transparent electrode (first electrode) in deionized water containing a cleaning solution, wash in an ultrasonic cleaner for 15 minutes, and again with deionized water, acetone, isopropyl alcohol (IPA) ) was washed three times each, and then dried in an oven at 130° C. for 5 hours. The ITO glass substrate cleaned as described above _{was exposed to O 2} plasma for 15 minutes to convert the surface of the substrate to a hydrophilic state. On it, PEDOT:PSS (poly(3,4-ethylenedioxythiophene)polystyrene sulfonate) was spin-coated at 3000rpm and baked at 150°C for 15 minutes to form a 40 nm thick PEDOT:PSS layer. After transferring the device to a glove box filled with argon under N _{2 atmosphere, a photoactive layer was formed.}

In order to form the photoactive layer, the compound of the present invention (compound 1 prepared in Example 1) as the electron acceptor (A) and PBDT-F as the electron donor (D) were mixed in chloroform in a weight ratio of A:D of 1.2: 1. (CF) was dissolved at a concentration of 14 mg/mL, 1-chloronaphthalene (1-CN) was added at 0.5 vol% and stirred at 45° C. for 3 hours to prepare a blend solution of Compound 1 and PBDT-F . After filtering the blend solution of Compound 1 and PBDT-F through a 0.45 μm (PTFE) syringe filter, spin coating on the PEDOT:PSS layer at 3000 rpm to prepare a photoactive layer with a thickness of 110±5 nm did. When an annealing step is included after formation of the photoactive layer, solvent vapor annealing (SVA) was first performed with chloroform (CF) for 60 seconds, and then secondary thermal annealing was performed at 100°C.

Then, as a cathode buffer layer on the photoactive layer, PDINN (2,9-bis(3-((3-(dimethylamino)propyl)amino)propyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone) solution (methanol, 1mg/ml) was spin-coated at 3000rpm, and finally, thermal evaporator under ^{high vacuum (less than 10 -6 torr)} A 120 nm thick Ag electrode was deposited as the top electrode through the

That is, an organic solar cell having a conventional structure of [Glass/ITO/PEDOT:PSS/photoactive layer (compound of the present invention: PBDT-F)/PDINN/Ag] was manufactured.

In order to investigate the photoelectric power characteristics of the fabricated organic solar cell, 100 mW sunlight under AM 1.5 condition was generated using a solar simulator and a radiant power meter, and Keithley 2400 SMU and a solar simulator (K201). LAB55; McScience Inc.) was used to measure current density-voltage characteristics of organic solar cells.

Each of V _oc (V) and J _sc (mA/cm ² ) represents a voltage value when the current is 0 and a current value when the voltage is 0 in the current-voltage curve of the fabricated device.

In addition, FF (fill factor) is calculated from Equation 1 below.

[Equation 1]

FF = V _mpp ㆍJ _mpp /V _oc ㆍJ _sc

(In Equation 1, _{each of V mpp} and J _mpp represents the voltage and current value at the point showing the maximum power when measuring the current-voltage of the manufactured device, and V _oc (V) and J _sc (mA/ cm ² ) Each represents a voltage value when the current is 0 and a current value when the voltage is 0 in the current-voltage curve of the fabricated device.)

Furthermore, the photoelectric conversion efficiency (%) is calculated from Equation 2 below.

[Equation 2]

Photoelectric conversion efficiency (%) = 100×FF×V _oc ㆍJ _sc /P _in

(In Equation 2, FF, V _oc and J _sc are as defined in Equation 1, and P _in represents the total energy of light incident on the device.)

_{Open-circuit voltage (V oc} ), short-circuit current (J _sc ), FF (Fill Factor), and photoelectric conversion efficiency (PCE), which are electrical characteristics of the produced organic solar cell, were checked, and the results are shown in Table 2 below. It was.

[Comparative Examples 1 and 2] Preparation of organic solar cells

Using the comparative compound Y6 instead of the compound of the present invention, organic solar cells were manufactured in the same manner as in Examples 7 and 8, and their characteristics were confirmed.

Example 7 Example 8 Comparative Example 1 Comparative Example 2 electron donor PBDT-F PBDT-F PBDT-F PBDT-F electron acceptor compound 1 compound 1 Y6 Y6 Annealing (5 min) - 2 ^nd 100 ℃ - 2 ^nd 100 ℃ SVA
(solvent vapor annealing) - 1 ^st CF 60s - 1 ^st CF 60s V _oc [V] 0.84 0.82 0.86 0.85 J _cs [mA/cm ² ] 24.97 25.21 22.36 23.90 FF 0.73 0.74 0.68 0.69 PCE _max (PCE _avg ) [%] 15.21 (15.01) 15.27 (15.12) 13.48 (13.09) 14.39 (14.03)

It was confirmed that the organic solar cell employing the compound according to the present invention as an electron acceptor in the photoactive layer can realize excellent photoelectric conversion efficiency. It can be seen that this is due to the structure in which aryloxy is bonded through alkylene to the nitrogen atom of pyrrole present in the characteristic substituent of the compound according to the present invention, specifically, in the central electron donor unit.

In addition, the organic solar cell employing the compound according to the present invention has excellent long-term stability, and despite the passage of a long period of time, no significant change in photoelectric conversion efficiency is observed, and the initial value is maintained and durability is excellent.

A dithiol compound with a center electron donor unit according to the invention Using the method of phenothiazine [3,2- b] - pyrrolo as benzo-thiadiazole (dithienothiophen [3,2- b] -pyrrolobenzothiadiazole) and electron acceptor unit in both ends thereof 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile or 2-(6-oxo-5,6-dihydro-4H-cyclopenta[c]thi It has an offen-4-ylidene) malononitrile-based group, and an aryloxyalkyl group is substituted for the pyrrole of the central electron donor unit, so it has excellent thermal and chemical stability as well as a good photoelectric conversion efficiency. It showed improved stability and durability.

In addition, the compound of the present invention exhibited excellent photoelectric conversion efficiency due to excellent compatibility with the electron donor while having improved electron affinity compared to the conventional fullerene-based electron acceptor as well as Y6, a known non-fullerene-based electron acceptor. At the same time, it was confirmed that the compound of the present invention can be applied as a compound that replaces the fullerene-based electron acceptor by showing the effect of significantly _{increasing the} open circuit voltage (V oc ) and the short-circuit current (J _{sc ).}

Therefore, when the compound according to the present invention is employed as a non-fullerene-based electron acceptor, it is possible to realize excellent photoelectric conversion efficiency as well as high short-circuit current (J _sc ) and FF, so that the fullerene derivative widely used as a conventional electron acceptor can be used. Used as an alternative compound, it can improve the photoelectric conversion efficiency of an organic solar cell, and at the same time significantly improve stability and durability.

Although the embodiments of the present invention have been described in detail as described above, those of ordinary skill in the art to which the present invention pertains within the scope not departing from the technical spirit of the present invention as defined in the appended claims. The present invention may be practiced with various modifications. Accordingly, modifications of future embodiments of the present invention will not depart from the technology of the present invention.

Claims (12)

A compound represented by the following formula (1):
[Formula 1]

[In Formula 1,
L ₁ and L ₂ are each independently C1-C30 alkylene;
W ₁ and W ₂ are each independently O or S;
Ar ₁ and Ar ₂ are each independently C6-C30 aryl or C3-C30 heteroaryl;
U ₁ is NR′ or S;
R' is C1-C30 alkyl;
R ₁ and R ₂ are each independently C1-C30 alkyl;
V ₁ and V ₂ are each independently a fused ring having methylidene as a linking group, and the fused rings are each independently C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1- It may be further substituted with one or more substituents selected from C30 alkyl, nitro and hydroxy, and -CH ₂ - of the fused ring is carbonyl, thiocarbonyl or

wherein R is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy, haloC1-C30 alkyl, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;
X ₁ to X ₄ are each independently O, S or Se;
The heteroaryl includes one or more heteroatoms selected from N, O, S and Se.] The method of claim 1,
The V ₁ and V ₂ are each independently represented by the following formula (A), the compound:
[Formula A]

[In Formula A,
Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;
A is a C6-C20 aromatic ring or a C3-C20 heteroaromatic ring, wherein the aromatic ring and the heteroaromatic ring are C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, haloC1-C30 alkyl , may be further substituted with one or more substituents selected from nitro and hydroxy.] 3. The method of claim 2,
The V ₁ and V ₂ are each independently represented by Formula B or Formula C, a compound:
[Formula B]

[Formula C]

[In the above formulas B and C,
Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;
one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;
R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;
Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl or an adjacent substituent It may be connected with R ₁₃ or R ₁₄ to form an aromatic fused ring;
R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.] 4. The method of claim 3,
Wherein V ₁ and V ₂ are represented by the following formula D, E, F or G, the compound:
[Formula D]

[Formula E]

[Formula F]

[Formula G]

[In the above formulas D to G,
Y ₁ and Y ₂ are each independently O or S;
R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyloxy;
R ₂₁ to R ₂₇ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano or haloC1-C30 alkyl.] The method of claim 1,
A compound represented by the following formula (2):
[Formula 2]

[In Formula 2, X ₁ to X ₄ , L ₁ , L ₂ , Ar ₁ , Ar ₂ , U ₁ , R ₁ and R ₂ are the same as defined in Formula 1 of claim 1 ;
V ₁ and V ₂ are each independently represented by Formula B or Formula C;
[Formula B]

[Formula C]

Y ₁ and Y ₂ are each independently O, S or CR ₁₁ R ₁₂ , R ₁₁ and R ₁₂ are each independently halogen, cyano, nitro, hydroxy, C1-C30 alkylcarbonyl or C1-C30 alkylcarbonyl nyloxy;
one of Z ₂ and Z ₃ is CR ₁₇ and the other is O, S or Se;
R ₁₇ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl;
Z ₁ is CR ₁₈ or N, wherein R ₁₈ is hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl or an adjacent substituent It may be connected with R ₁₃ or R ₁₄ to form an aromatic fused ring;
R ₁₃ to R ₁₆ are each independently hydrogen, C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano, nitro, hydroxy or haloC1-C30 alkyl.] 6. The method of claim 5,
A compound represented by the following formula 3, 4, 5 or 6:
[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[In Formulas 3 to 6,
X ₁ to X ₄ are each independently O, S or Se;
U ₁ is NR′ or S;
R' is C1-C30 alkyl;
R ₁ and R ₂ are each independently C1-C30 alkyl;
Q ₁ to Q ₆ are each independently CH or N;
R ₃₁ to R ₃₅ are each independently C1-C30 alkyl, C1-C30 alkoxy, C1-C30 alkylthio, halogen, cyano or haloC1-C30 alkyl;
m and n are each independently an integer from 0 to 2;
x and y are each independently an integer from 1 to 30.] 8. The method of claim 7,
wherein X ₁ to X ₄ are each independently S; U ₁ is S; R ₁ and R ₂ are each independently C7-C30 alkyl; Q ₁ to Q ₆ are each independently CH; R ₃₁ and R ₃₂ are each independently C1-C10 alkyl, C1-C10 alkoxy or halogen; R ₃₃ to R ₃₅ are each independently hydrogen or C 1 -C 10 alkyl; m and n are each independently an integer from 0 to 2; x and y are each independently an integer from 5 to 30. An organic electronic device comprising the compound according to any one of claims 1 to 7. 9. The method of claim 8,
The organic electronic device is an organic solar cell, an organic thin film transistor, an organic memory, an organophotoreceptor or an organic photosensor. 10. The method of claim 9,
The organic electronic device is an organic solar cell. 11. The method of claim 10,
The compound is included in the photoactive layer of the organic solar cell, an organic electronic device. 12. The method of claim 11,
The compound is used as an electron acceptor, an organic electronic device.

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