KR20180126814A - Organic solar cell - Google Patents

Abstract

The present disclosure relates to organic solar cells.

Description

Organic solar cell {ORGANIC SOLAR CELL}

The present disclosure relates to organic solar cells.

Organic solar cells are devices that can convert solar energy directly into electric energy by applying photovoltaic effect. Solar cells can be divided into inorganic solar cells and organic solar cells depending on the material constituting the thin film. A typical solar cell is made of p-n junction by doping crystalline silicon (Si), which is an inorganic semiconductor. Electrons and holes generated by absorption of light are diffused to the p-n junction, accelerated by the electric field, and moved to the electrode. The power conversion efficiency of this process is defined as the ratio of the power given to the external circuit to the solar power entering the solar cell, and is achieved up to 24% when measured under the current standardized virtual solar irradiation conditions. However, since conventional inorganic solar cells have already been limited in economic efficiency and supply / demand of materials, organic semiconductor solar cells, which are easy to process, have various functions and are inexpensive, are seen as long-term alternative energy sources.

Solar cells are important to increase efficiency so that they can output as much electrical energy as possible from solar energy. In order to increase the efficiency of such a solar cell, it is also important to generate as much excitons as possible in the semiconductor, but it is also important to draw out generated charges without loss. One of the causes of loss of charge is that the generated electrons and holes are destroyed by recombination. Various methods have been proposed as methods for transferring generated electrons and holes to electrodes without loss, but most of them require additional processing, which may increase the manufacturing cost.

Two-layer organic photovoltaic cells (C. W. Tang, Appl. Phys. Lett., 48, 183. (1996) Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Science, 270, 1789. (1995)).

It is an object of the present invention to provide an organic solar cell.

In one embodiment of the present disclosure, the first electrode; A second electrode facing the first electrode; And at least one organic layer disposed between the first electrode and the second electrode and including a photoactive layer, wherein the photoactive layer includes an electron donor and an electron acceptor, wherein the electron donor is represented by the following Formula 1 Gt; And a second unit represented by the following formula (2) or (3), wherein the electron acceptor comprises a non-fullerene-based compound.

[Chemical Formula 1]

 (2)

(3)

In the above Formulas 1 to 3,

X 1 and X 2 are the same or different and each independently represents a substituted or unsubstituted monocyclic or polycyclic heteroaryl group; Or a substituted or unsubstituted monocyclic or polycyclic aryl group,

Y1 to Y10 are the same or different and are each independently S or Se,

R1 to R12 are the same or different from each other, and each independently hydrogen; Or a substituted or unsubstituted straight or branched alkyl group,

a1, a2, a3 and a4 are each 1 or 2,

When a1, a2, a3 and a4 are each 2, the structures in the two parentheses are equal to or different from each other.

The organic solar cell according to one embodiment of the present invention is excellent in thermal stability by using the above polymer as an electron source and using the non-fullerene compound as an electron acceptor, great.

The polymer according to one embodiment of the present invention has a high HOMO energy level and thus has excellent open-circuit voltage characteristics as the electron mobility of the photoactive layer.

In addition, the polymer according to one embodiment of the present invention has rigid .pi.-spacers, and the organic solar cell including the photoactive layer as an electron hole has excellent short-circuit current and fill factor.

1 is a view illustrating an organic solar cell according to an embodiment of the present invention.
Fig. 2 is a diagram showing the UV-vis absorption spectrum of the polymers 1 to 3 in a film state.
3 is a graph showing the HOMO and LUMO energies of the polymers 1 to 3 and the above formula A (ITIC).
Fig. 4 is a diagram showing the UV-vis absorption spectrum of the polymers 4 to 7 in a solution state. Fig.
Fig. 5 is a diagram showing the UV-vis absorption spectrum of the polymers 4 to 7 in a film state. Fig.

Hereinafter, the present invention will be described in more detail.

As used herein, the term "unit" means a repeating structure contained in a monomer of a polymer, wherein the monomer is bonded to the polymer by polymerization.

In this specification, the meaning of 'including unit' means that it is included in the main chain in the polymer.

Whenever a component is referred to as "comprising ", it is understood that it may include other components as well, without departing from the other components unless specifically stated otherwise.

When a member is referred to herein as being "on " another member, it includes not only a member in contact with another member but also another member between the two members.

In this specification, the energy level means the magnitude of energy. Therefore, even when the energy level is displayed in the minus (-) direction from the vacuum level, the energy level is interpreted to mean the absolute value of the energy value. For example, the HOMO energy level means the distance from the vacuum level to the highest occupied molecular orbital. The LUMO energy level also means the distance from the vacuum level to the lowest unoccupied molecular orbital.

In one embodiment of the present disclosure, the first electrode; A second electrode facing the first electrode; And at least one organic layer disposed between the first electrode and the second electrode and including a photoactive layer, wherein the photoactive layer includes an electron donor and an electron acceptor, wherein the electron donor is represented by the following Formula 1 Gt; And a second unit represented by the following formula (2) or (3), wherein the electron acceptor comprises a non-fullerene-based compound.

The organic solar cell according to one embodiment of the present invention has improved light-to-electricity conversion efficiency by controlling the energy level of the molecule and controlling the extinction coefficient through the change of the electron chain side chain.

The organic solar cell according to one embodiment of the present invention can be used to induce a non-fullerene-based compound used as an electron donor and an electron donor to have an ideal molecular arrangement through a change in the π-spacer between the electron donor- .

Illustrative examples of such substituents are set forth below, but are not limited thereto.

The term "substituted" means that the hydrogen atom bonded to the carbon atom of the compound is replaced with another substituent, and the substituted position is not limited as long as the substituent is a substitutable position, , Two or more substituents may be the same as or different from each other.

As used herein, the term " substituted or unsubstituted " A halogen group; A nitrile group; A nitro group; Imide; Amide group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted aryloxy group; A substituted or unsubstituted alkylthio group; A substituted or unsubstituted arylthio group; A substituted or unsubstituted alkylsulfoxy group; A substituted or unsubstituted arylsulfoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; And a substituted or unsubstituted heterocyclic group, or two or more of the substituents exemplified above are substituted with a substituent to which they are linked, or have no substituent. For example, the "substituent group to which two or more substituents are connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group, and may be interpreted as a substituent in which two phenyl groups are connected.

In the present specification, the number of carbon atoms in the imide group is not particularly limited, but is preferably 1 to 30 carbon atoms. Specifically, it may be a compound having the following structure, but is not limited thereto.

In the present specification, the amide group may be mono- or di-substituted with nitrogen of the amide group with hydrogen, a straight-chain, branched or cyclic alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, examples of the halogen group include fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 50. Specific examples include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec- N-pentyl, 3-dimethylbutyl, 2-ethylbutyl, heptyl, n-hexyl, Cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethyl Heptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl and the like.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, and specifically includes cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, But are not limited to, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert- butylcyclohexyl, cycloheptyl, Do not.

In the present specification, the alkoxy group may be linear, branched or cyclic. The number of carbon atoms of the alkoxy group is not particularly limited, but is preferably 1 to 20 carbon atoms. Specific examples include methoxy, ethoxy, n-propoxy, isopropoxy, i-propyloxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentyloxy, neopentyloxy, N-hexyloxy, n-hexyloxy, 3,3-dimethylbutyloxy, 2-ethylbutyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, benzyloxy, But is not limited thereto.

In the present specification, the alkenyl group may be straight-chain or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 40. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, Butenyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, (Diphenyl-1-yl) vinyl-1-yl, stilbenyl, stilenyl, and the like.

In the present specification, when the aryl group is a monocyclic aryl group, the number of carbon atoms is not particularly limited, but is preferably 6 to 25 carbon atoms. Specific examples of the monocyclic aryl group include a phenyl group, a biphenyl group, a terphenyl group, and the like, but are not limited thereto.

In the present specification, when the aryl group is a polycyclic aryl group, the number of carbon atoms is not particularly limited. And preferably has 10 to 24 carbon atoms. Specific examples of the polycyclic aryl group include naphthyl, anthracenyl, phenanthryl, pyrenyl, perylenyl, klychenyl, fluorenyl, and the like.

In the present specification, the fluorenyl group may be substituted, and adjacent substituents may be bonded to each other to form a ring.

,

,

,

,

,

,

및

등이 될 수 있다. 다만, 이에 한정되는 것은 아니다.When the fluorenyl group is substituted,

,

,

,

,

,

,

And

And the like. However, the present invention is not limited thereto.

In the present specification, the heterocyclic group includes at least one non-carbon atom or hetero atom, and specifically, the hetero atom may include at least one atom selected from the group consisting of O, N, Se, and S, and the like. The number of carbon atoms of the heterocyclic group is not particularly limited, but is preferably 2 to 60 carbon atoms. Examples of the heterocyclic group include a thiophene group, a furan group, a pyrrolyl group, an imidazole group, a thiazole group, an oxazole group, an oxadiazole group, a triazole group, a pyridyl group, a bipyridyl group, a pyrimidyl group, A pyrazinyl group, a pyrazinyl group, a quinolyl group, a quinazolyl group, a quinoxalyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrimidinyl group, a pyrazinopyranyl group, an isoquinoline group, , A carbazole group, a benzoxazole group, a benzimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuranyl group, a phenanthroline, a thiazolyl group, A thiadiazolyl group, a phenothiazinyl group, and a dibenzofuranyl group, but the present invention is not limited thereto.

In the present specification, the number of carbon atoms of the amine group is not particularly limited, but is preferably 1 to 30. The amine group may be substituted on the N atom with an aryl group, an alkyl group, an arylalkyl group, and a heterocyclic group. Specific examples of the amine group include a methylamine group, a dimethylamine group, an ethylamine group, a diethylamine group, A phenol group, a naphthylamine group, a biphenylamine group, an anthracenylamine group, a 9-methyl-anthracenylamine group, a diphenylamine group, a phenylnaphthylamine group, a ditolylamine group, a phenyltolylamine group, And the like, but the present invention is not limited thereto.

In the present specification, the aryl group in the aryloxy group, the arylthioxy group and the arylsulfoxy group is the same as the aforementioned aryl group. Specific examples of the aryloxy group include phenoxy, p-tolyloxy, m-tolyloxy, 3,5-dimethyl-phenoxy, 2,4,6-trimethylphenoxy, Naphthyloxy, 4-methyl-1-naphthyloxy, 5-methyl-2-naphthyloxy, 1-anthryloxy, 2-anthryl Phenanthryloxy, 9-phenanthryloxy and the like. Examples of the arylthioxy group include phenylthio group, 2-methylphenylthio group, 4-tert-butylphenyl And the like. Examples of the aryl sulfoxy group include a benzene sulfoxy group and a p-toluenesulfoxy group, but the present invention is not limited thereto.

In the present specification, the alkyl group in the alkylthio group and alkylsulfoxy group is the same as the alkyl group described above. Specific examples of the alkyloxy group include a methylthio group, an ethylthio group, a tert-butylthio group, a hexylthio group and an octylthio group. Examples of the alkylsulfoxy group include a mesyl group, an ethylsulfoxy group, a propylsulfoxy group, But are not limited thereto.

In the present specification, the non-fullerene-based compound is represented by the following formula (A).

(A)

According to one embodiment of the present invention, the compound represented by the formula (A) has higher thermal stability than the fullerene compound.

According to an embodiment of the present invention, an organic solar cell including the compound represented by the formula (A) as an electron hole of the photoactive layer and containing the polymer as an electron acceptor of the photoactive layer has excellent thermal stability, Is excellent.

According to one embodiment of the present invention, in the above formula (1), Y1 and Y2 are S.

According to one embodiment of the present invention, the formula (1) is represented by the following formula (1-1).

[Formula 1-1]

In Formula 1-1,

The definitions of R1, R2, X1 and X2 are the same as those defined in the above formula (1).

According to one embodiment of the present invention, in the above formula (1), Y3 to Y6 are S.

According to one embodiment of the present invention, the formula (2) is represented by the following formula (2-1).

[Formula 2-1]

In Formula 2-1,

The definitions of R3 to R8, a1 and a2 are the same as defined in the above formula (2).

According to one embodiment of the present invention, Y3, Y4, Y7 to Y10 are S in the formula (1).

 According to one embodiment of the present invention, the formula (3) is represented by the following formula (3-1).

[Formula 3-1]

In Formula 3-1,

The definition of R7 to R12, a3 and a4 is the same as defined in the above formula (3).

According to one embodiment of the present invention, in Formula 1, X 1 and X 2 are the same or different and each independently is a thioalkoxy group or a thiophene group substituted with a silyl group; A benzothiophene group substituted with an alkyl group; Or a phenyl group substituted with an alkoxy group.

According to one embodiment of the present invention, in the general formula (1), X1 and X2 are the same or different and independently selected from the following structures.

In the above structure,

R101, R103 to R105, R107 and R109, which are the same or different, are each independently a linear or branched alkyl group,

R102, R106, R108 and R110 are hydrogen,

r102 and r106 are each 1 or 2, r108 and r110 are each an integer of 1 to 4,

은 상기 화학식 1에 결합되는 부위이다.

Is a moiety bonded to the formula (1).

In this specification, the energy-level control and the extinction coefficient of the molecule are controlled through the change of the side chain of R101, R103 to R105, R107 and R109 of the above structure to improve the photo-electric conversion efficiency.

According to one embodiment of the present invention, R101, R103 to R105, R107 and R109 are the same or different and are each independently a branched chain alkyl group.

According to one embodiment of the present invention, R101, R103 to R105, R107 and R109 are the same or different and each independently is a branched chain alkyl group having 3 to 20 carbon atoms.

According to one embodiment of the present invention, R101, R103 to R105, R107 and R109 are the same or different from each other and are each independently a 2-ethylhexyl group, an n-butyl group, or a 2-butyloctyl group.

According to one embodiment of the present invention, the polymer includes a unit represented by the following formula (4) or (5).

[Chemical Formula 4]

[Chemical Formula 5]

In the above formulas (4) and (5)

l is a molar fraction, 0 < l < 1,

m is a molar fraction, 0 < m < 1,

l + m = 1,

A is a first unit represented by the above formula (1)

B is a second unit represented by the above formula (2) or (3)

n is the number of repeating units, and is an integer of 1 to 10,000.

According to one embodiment of the present invention, in the above formulas (4) and (5), A is the formula (1-1).

According to one embodiment of the present invention, in Formulas (4) and (5), B is the formula (2-1) or (3-1), and a1, a2, a3 and a4 are 1.

According to one embodiment of the present invention, the polymer includes units represented by any one of the following formulas (4-1), (4-2), (5-1) and (5-2).

[Formula 4-1]

[Formula 4-2]

[Formula 5-1]

[Formula 5-2]

In Formulas (4-1), (4-2), (5-1) and (5-2)

The definitions of R1, R2, X1 and X2 are the same as defined in Formula 1,

The definitions of R3 to R8, a1 and a2 are the same as defined in the above formula (2)

R9 to R12, a3 and a4 are the same as defined in the above formula (3)

l is a molar fraction, 0 < l < 1,

m is a molar fraction, 0 < m < 1,

l + m = 1,

n is the number of repeating units, and is an integer of 1 to 10,000.

According to one embodiment of the present disclosure, R1 to R6 and R9 to R12 are hydrogen.

According to one embodiment of the present invention, R7 and R8 are the same or different and are each independently a branched chain alkyl group.

According to one embodiment of the present invention, R7 and R8 are the same or different and each independently represents a branched chain alkyl group having 3 to 20 carbon atoms.

According to one embodiment of the present disclosure, R7 and R8 are 2-ethylhexyl groups.

In one embodiment of the present disclosure, l is 0.5.

In another embodiment, m is 0.5.

In another embodiment of the present disclosure, l is 0.75.

In one embodiment of the present disclosure, m is 0.25.

In one embodiment of the present disclosure, the polymer is a random polymer. In addition, the solubility is improved in the case of the random polymer, which is economical in time and cost in the manufacturing process of the device.

In one embodiment of the present invention, the polymer includes units represented by any one of the following formulas (4-1-1) to (4-1-3).

[Formula 4-1-1]

[Formula 4-1-2]

[Formula 4-1-3]

[Formula 4-2-1]

[Formula 4-2-2]

[Formula 4-2-3]

[Chemical Formula 4-2-4]

In Formulas 4-1-1 to 4-1-3 and 4-2-1 to 4-2-4,

n is the number of repeating units, and is an integer of 1 to 10,000.

In one embodiment of the present invention, the terminal group of the polymer is a heterocyclic group or an aryl group.

In one embodiment of the present disclosure, the end group of the polymer is a 4- (trifluoromethyl) phenyl group.

In one embodiment of the present disclosure, the terminal group of the polymer is a bromo-thiophene group.

In another embodiment, the terminal group of the polymer is a trifluoro-benzene group.

In one embodiment of the present disclosure, the number average molecular weight of the polymer is preferably from 5,000 g / mol to 1,000,000 g / mol.

In one embodiment of the present disclosure, the polymer may have a molecular weight distribution of from 1 to 10. Preferably, the polymer has a molecular weight distribution of from 1 to 3.

The lower the molecular weight distribution and the higher the number average molecular weight, the better the electrical and mechanical properties.

In addition, the number-average molecular weight is preferably 100,000 or less in order to have a solubility of more than a certain level and to be advantageous in application of a solution coating method.

Pd (PPh ₃ ) ₄ was added to the monomer of each unit of the above polymer as a solvent and polymerization was carried out at 100 ° C for 17 hours to polymerize.

In addition, the polymers according to the present disclosure can be prepared by a multistage chemical reaction. The monomers are produced through an alkylation reaction, a Grignard reaction, a Suzuki coupling reaction, a Stille coupling reaction, and the like, followed by a carbon-carbon coupling reaction such as a steel coupling reaction, . &Lt; / RTI &gt; When the substituent to be introduced is a boronic acid or a boronic ester compound, it can be prepared through a Suzuki coupling reaction. When the substituent to be introduced is tributyltin or trimethyltin ) Compound, it may be prepared through a steel coupling reaction, but the present invention is not limited thereto.

According to an embodiment of the present disclosure, the electron donor and the electron acceptor are contained in a weight ratio of 1:10 to 10: 1, and preferably the electron donor and the electron acceptor are contained in a weight ratio of 1: 1.

An organic solar cell according to an embodiment of the present invention includes a first electrode, a photoactive layer, and a second electrode. The organic solar cell may further include a substrate, a hole transporting layer, and / or an electron transporting layer.

In one embodiment of the present invention, when the organic solar cell receives photons from an external light source, electrons and holes are generated between the electron beams and the electron acceptors. The generated holes are transported to the anode through the electron donor layer.

1 illustrates an organic solar cell according to an embodiment of the present invention.

In one embodiment of the present disclosure, the organic solar cell may further include an additional organic layer. The organic solar cell can reduce the number of organic layers by using organic materials having various functions at the same time.

In one embodiment of the present disclosure, the first electrode is an anode, and the second electrode is a cathode. In another embodiment, the first electrode is a cathode and the second electrode is an anode.

In one embodiment of the present disclosure, the organic solar cell may be arranged in the order of the cathode, the photoactive layer, and the anode, and may be arranged in the order of the anode, the photoactive layer, and the cathode, but is not limited thereto.

In another embodiment, the organic solar cell may be arranged in the order of an anode, a hole transporting layer, a photoactive layer, an electron transporting layer and a cathode, and may be arranged in the order of a cathode, an electron transporting layer, a photoactive layer, a hole transporting layer, , But is not limited thereto.

In one embodiment of the present invention, the organic solar cell is a normal structure. The normal structure may mean that the anode is formed on the substrate. Specifically, in one embodiment of the present invention, when the organic solar cell is a normal structure, the first electrode formed on the substrate may be an anode.

In one embodiment of the present invention, the organic solar cell is an inverted structure. The inverted structure may mean that the cathode is formed on the substrate. More specifically, in one embodiment of the present invention, when the organic solar cell is an inverted structure, the first electrode formed on the substrate may be a cathode.

In one embodiment of the present invention, the organic solar cell is a tandem structure. In this case, the organic solar cell may include two or more photoactive layers. The organic solar cell according to one embodiment of the present disclosure may have one photoactive layer or two or more layers.

In another embodiment, a buffer layer may be provided between the photoactive layer and the hole transporting layer or between the photoactive layer and the electron transporting layer. At this time, a hole injection layer may be further provided between the anode and the hole transport layer. Further, an electron injecting layer may be further provided between the cathode and the electron transporting layer.

In one embodiment of the present disclosure, the electron donor and the electron acceptor constitute a bulk heterojunction (BHJ).

Bulk heterojunction means that the electron donor material and the electron acceptor material are mixed in the photoactive layer.

In one embodiment of the present disclosure, the photoactive layer further comprises an additive.

In one embodiment of the present disclosure, the molecular weight of the additive is from 50 g / mol to 300 g / mol.

In another embodiment, the boiling point of the additive is an organic matter of 30 占 폚 to 300 占 폚.

In this specification, an organic substance means a substance containing at least one carbon atom.

In one embodiment, the additive is selected from the group consisting of 1,8-diiodooctane, 1-chloronaphthalene (1-CN), diphenylether (DPE) , Octane dithiol, and tetrabromothiophene. The additive may further include one or two additives selected from the group consisting of tetrabromothiophene, octane dithiol, and tetrabromothiophene.

In one embodiment of the present invention, the photoactive layer is a bilayer structure including an n-type organic layer and a p-type organic layer, and the p-type organic layer includes the polymer.

In this specification, the substrate may be a glass substrate or a transparent plastic substrate having excellent transparency, surface smoothness, ease of handling, and waterproofness, but is not limited thereto, and is not limited as long as it is a substrate commonly used in organic solar cells. Specific examples include glass or polyethylene terephthalate, polyethylene naphthalate (PEN), polypropylene (PP), polyimide (PI), and triacetyl cellulose (TAC) But is not limited thereto.

The anode electrode may be a transparent material having excellent conductivity, but is not limited thereto. Metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); ZnO: Al or SnO _2: a combination of a metal and an oxide such as Sb; Conductive polymers such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDOT), polypyrrole and polyaniline.

The method of forming the anode electrode is not particularly limited and may be applied to one surface of the substrate or may be coated in a film form using, for example, sputtering, E-beam, thermal evaporation, spin coating, screen printing, inkjet printing, doctor blade or gravure printing . &Lt; / RTI &gt;

When the anode electrode is formed on a substrate, it may undergo cleaning, moisture removal and hydrophilic reforming processes.

For example, the patterned ITO substrate is sequentially cleaned with a detergent, acetone, and isopropyl alcohol (IPA), and then heated on a heating plate at 100 ° C to 150 ° C for 1 minute to 30 minutes, preferably at 120 ° C for 10 minutes Dried, and the substrate surface is hydrophilically reformed when the substrate is completely cleaned.

Through such surface modification, the junction surface potential can be maintained at a level suitable for the surface potential of the photoactive layer. Further, in the modification, the formation of the polymer thin film on the anode electrode is facilitated, and the quality of the thin film may be improved.

The anode electrode pre-treatment techniques include a) surface oxidation using a parallel plate discharge, b) a method of oxidizing the surface through ozone generated using UV ultraviolet radiation in vacuum, and c) oxygen radicals produced by the plasma And the like.

One of the above methods can be selected depending on the state of the anode electrode or the substrate. However, whichever method is used, it is preferable to prevent oxygen from escaping from the surface of the anode electrode or the substrate and to suppress the residual of moisture and organic matter as much as possible. At this time, the substantial effect of the preprocessing can be maximized.

As a specific example, a method of oxidizing the surface through ozone generated using UV can be used. At this time, the ITO substrate patterned after the ultrasonic cleaning is baked on a hot plate, dried well, then put into a chamber, and is irradiated with ozone generated by reaction of oxygen gas with UV light by operating a UV lamp The patterned ITO substrate can be cleaned.

However, the method of modifying the surface of the patterned ITO substrate in the present specification is not particularly limited, and any method may be used as long as it is a method of oxidizing the substrate.

The cathode electrode may be a metal having a small work function, but is not limited thereto. Specifically, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Layer structure such as LiF / Al, LiO ₂ / Al, LiF / Fe, Al: Li, Al: BaF ₂ and Al: BaF ₂ : Ba.

The cathode may be deposited in a thermal evaporator having a degree of vacuum of 5 x 10 ^{&lt; -7} &gt; torr or less, but the method is not limited thereto.

The hole transporting layer and / or the electron transporting layer material efficiently transfer electrons and holes separated from the photoactive layer to the electrode, and the material is not particularly limited.

The hole transport layer material may include poly (3,4-ethylenediocythiophene) doped with poly (styrenesulfonic acid) (PEDOT: PSS), molybdenum oxide (MoO _x ); Vanadium oxide (V ₂ O ₅ ); Nickel oxide (NiO); And tungsten oxide (WO _x ), but the present invention is not limited thereto.

The electron transport layer material may be electron-extracting metal oxides, specifically a metal complex of 8-hydroxyquinoline; Complexes containing Alq ₃ ; Metal complexes including Liq; LiF; Ca; Titanium oxide (TiO _x ); Zinc oxide (ZnO); And cesium carbonate (Cs ₂ CO ₃ ), but the present invention is not limited thereto.

The photoactive layer may be formed by dissolving a photoactive material such as an electron donor and / or an electron donor in an organic solvent, and then applying the solution by spin coating, dip coating, screen printing, spray coating, doctor blade, brush painting, But is not limited to the method.

Hereinafter, the present invention will be described in detail by way of examples with reference to the drawings. However, the embodiments according to the present disclosure can be modified in various other forms, and the scope of the present specification is not construed as being limited to the embodiments described below. Embodiments of the present disclosure are provided to more fully describe the present disclosure to those of ordinary skill in the art.

<Production Example>

Production Example 1. Preparation of Polymer 1

(4,8-bis (5- (2-butyloctyl) benzo [b] thiophen-2-yl) benzo [1,2- b: 4,5- b '] dithiophene- 6-diyl) bis (trimethylstannane) (400 mg) and 1,3-bis (5-bromothiophen-2-yl) -5,7-bis (2-ethylhexyl) -4H, 8H- (4-fluorophenyl) -4,5-c '] dithiophene-4,8-dione (368 mg, 1 eq) and Pd (PPh ₃ ) ₄ (0.01 g, 0.03 eq) were injected and injected with 16 mL of toluene and 1 mL of dimethylformamide Respectively. And refluxed at 100 ° C for 17 hours. After completion of the reaction through methanol, the polymer synthesized through methanol, nucleic acid and acetone was purified to obtain the following Polymer 1.

Production Example 2. Preparation of Polymer 2

2-yl) benzo [1,2-b: 4,5-b '] dithiophene-2,6-diyl ) bis (trimethylstannane) instead of (4,8-bis (3- ((2-ethylhexyl) oxy) phenyl) benzo [1,2- b: 4,5- b '] dithiophene-2,6- trimethylstannane) was used as the initiator, to obtain Polymer 2 shown below.

Production Example 3. Preparation of Polymer 3

2-yl) benzo [1,2-b: 4,5-b '] dithiophene-2,6-diyl (4,8-bis (5 - ((2-ethylhexyl) thio) thiophen-2-yl) benzo [1,2- b: 4,5- b '] dithiophene- diyl) bis (trimethylstannane) instead of bis (trimethylstannane).

[Polymer 1]

[Polymer 2]

[Polymer 3]

[Polymer 4]

[Polymer 5]

[Polymer 6]

[Polymer 7]

FIG. 3 is a graph showing the HOMO and LUMO energies of the polymers 1 to 3 and the above formula A (ITIC), and FIG. 4 5 shows the UV-vis absorption spectrum of the polymers 4 to 7 in a film state, and Tables 1 to 7 show UV-vis absorption spectra of the polymers 4 to 7 in the solution state. Table 1 shows the physical properties of Polymers 1 to 7.

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 1 19047/26600 / 2.25 616 587 709 Optical
E _g ^opt
(eV) ^[a] HOMO
(eV) ^[a]
CV LUMO
(eV) ^[a]
CV 1.74 -5.31 -3.57

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 2 22305/46836 / 2.09 616 607 669 Optical
E _g ^opt
(eV) ^[a] HOMO
(eV) ^[a]
CV LUMO
(eV) ^[a]
CV 1.85 -5.30 -3.45

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 3 84389/87133 / 1.06 559 635 697 Optical
E _g ^opt
(eV) ^[a] HOMO
(eV) ^[a]
CV LUMO
(eV) ^[a]
CV 1.77 -5.29 -3.52

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 4 21041/39977 / 1.89 532 555 672 Optical
E _g ^opt
(eV) ^[a] 1.84

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 5 23541/41902 / 1.78 552 566 678 Optical
E _g ^opt
(eV) ^[a] 1.82

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 6 22145/46504 / 2.10 505 548 660 Optical
E _g ^opt
(eV) ^[a] 1.87

polymer Mn / Mw / D
(g / mol) Solution Film ^[a] λ _{max , abs}
(nm) λ _max
(nm) λ _edge
(nm) Polymer 7 19547/36421 / 1.86 516 555 660 Optical
E _g ^opt
(eV) ^[a] 1.87

In Table 1 to 7, Solution λ _max means the maximum absorption wavelength of the polymer 1 to 7 in the solution state, Film λ _max means the maximum absorption wavelength of the polymer 1 to 7 in the film state, and Film λ _edge means the absorption _edge of the polymer 1 to 7 in the film state, and Optical E _g ^opt means the HOMO and LUMO energy band gap of the polymer 1 to 7 in the film state.

<Examples>

Example  1-1. Manufacture of organic solar cell

A composite solution was prepared by dissolving the above polymer 2 and the above-mentioned formula A (ITIC) annealed at 120 ° C in a 1: 1 mixture of chlorobenzene (CB). At this time, the concentration was adjusted to 2 wt%, and 0.5 vol% of 1,8-diiodooctane (DIO: 1,8-diiodooctane) was added to the complex solution. The organic solar cell has an inverted structure of ITO / ZnO NP / photoactive layer / MoO ₃ / Ag.

A glass substrate (11.5 Ω / □) coated with a 1.5 cm × 1.5 cm bar type ITO was subjected to ultrasonic cleaning using distilled water, acetone, and 2-propanol, and the ITO surface was subjected to ozone treatment for 10 minutes ZnO NP (ZnO nanograde N-10 2.5 wt% in 1-butanol, filtered to 0.45 μm PTFE) was spin coated on the ZnO NP solution at 4000 rpm for 40 seconds, The remaining solvent was removed by heat treatment to complete the electron transport layer. For the coating of the photoactive layer, a complex solution of the above polymer 2 and the above-mentioned formula A (ITIC) was spin-coated at 70 DEG C at 1700 rpm for 25 seconds to a thickness of 80 to 100 nm. In the thermal evaporator, MoO ₃ was thermally deposited at a rate of 0.2 Å / s at 10 ^-7 Torr to a thickness of 10 nm to prepare a hole transport layer. In this order, Ag was deposited in a thermal evaporator at a rate of 1 Å / s to form a 100 nm organic solar cell.

Example  1-2. Manufacture of organic solar cell

The same procedure as in Example 1-1 was followed except that the complex solution of the polymer 2 and the compound of the formula (ITIC) was spin-coated at 2100 rpm instead of 1700 rpm for coating the photoactive layer in Example 1-1. .

Example  1-3. Manufacture of organic solar cell

In the same manner as in Example 1-1, except that the complex solution of Polymer 2 and the above-mentioned formula A (ITIC) was spin-coated at 2500 rpm instead of 1700 rpm for coating the photoactive layer in Example 1-1 An organic solar cell was prepared.

Example  1-4. Manufacture of organic solar cell

In the same manner as in Example 1-1, except that the complex solution of the polymer 2 and the compound of the formula (ITIC) was spin-coated at 2900 rpm instead of 1700 rpm to a thickness of 85 nm for coating the photoactive layer in Example 1-1 An organic solar cell was prepared.

Comparative Example  1-1. Manufacture of organic solar cell

The polymer 2 and PCBM were dissolved in chlorobenzene (CB) at a ratio of 1: 1 to prepare a composite solution. At this time, the concentration was adjusted to 2 wt%, and 3 vol% of 1,8-diiodooctane (DIO: 1,8-diiodooctane) was added to the complex solution. The organic solar cell has an inverted structure of ITO / ZnO NP / photoactive layer / MoO ₃ / Ag.

A glass substrate (11.5 Ω / □) coated with a 1.5 cm × 1.5 cm bar type ITO was subjected to ultrasonic cleaning using distilled water, acetone, and 2-propanol, and the ITO surface was subjected to ozone treatment for 10 minutes ZnO NP (ZnO nanograde N-10 2.5 wt% in 1-butanol, filtered to 0.45 μm PTFE) was spin coated on the ZnO NP solution at 4000 rpm for 40 seconds, The remaining solvent was removed by heat treatment to complete the electron transport layer. For the coating of the photoactive layer, the composite solution of Polymer 2 and PCBM was spin-coated at 70 DEG C and 700 rpm for 25 seconds to a thickness of 80 to 100 nm. In the thermal evaporator, MoO ₃ was thermally deposited at a rate of 0.2 Å / s at 10 ^-7 Torr to a thickness of 10 nm to prepare a hole transport layer. In this order, Ag was deposited in a thermal evaporator at a rate of 1 Å / s to form a 100 nm organic solar cell.

Comparative Example  1-2. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Comparative Example 1-1, except that the complex solution of Polymer 2 and PCBM was spin-coated at 900 rpm instead of 700 rpm for coating the photoactive layer in Comparative Example 1-1.

Comparative Example  1-3. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Comparative Example 1-1 except that the complex solution of Polymer 2 and PCBM was spin-coated at 1100 rpm instead of 700 rpm for coating the photoactive layer in Comparative Example 1-1.

Comparative Example  1-4. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Comparative Example 1-1, except that the complex solution of Polymer 2 and PCBM was spin-coated at 1300 rpm instead of 700 rpm for coating the photoactive layer in Example 1-1. Respectively.

Example  2-1. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-1, except that Polymer 1 was used instead of Polymer 2 in Example 1-1.

Example  2-2. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-2, except that Polymer 1 was used instead of Polymer 2 in Example 1-2.

Example  2-3. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-3, except that Polymer 1 was used instead of Polymer 2 in Example 1-3, and the thickness of the photoactive layer was spin-coated to 77 nm.

Example  2-4. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-4, except that Polymer 1 was used instead of Polymer 2 in Example 1-4.

Example  3-1. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-1, except that Polymer 3 was used instead of Polymer 2 in Example 1-1.

Example  3-2. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-2, except that Polymer 3 was used instead of Polymer 2 in Example 1-2.

Example  3-3. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-3, except that Polymer 3 was used instead of Polymer 2 in Example 1-3, and the thickness of the photoactive layer was spin-coated to 80 nm.

Example  3-4. Manufacture of organic solar cell

An organic solar cell was prepared in the same manner as in Example 1-4, except that Polymer 3 was used instead of Polymer 2 in Example 1-4.

Example  4-1. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 4 was used in place of the polymer 2 in Example 1-1 and the complex solution of the polymer 4 and the polymer A (ITIC) was spin-coated at 1500 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  4-2. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 4 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 4 and the compound of Formula A (ITIC) was spin-coated at 1800 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  4-3. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 4 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 4 and the compound of Formula A (ITIC) was spin-coated at 2100 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  4-4. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 4 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 4 and the polymer A (ITIC) was spin-coated at 2400 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  5-1. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 5 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 5 and the compound of Formula A (ITIC) was spin-coated at 1500 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  5-2. Manufacture of organic solar cell

The procedure of Example 1-1 was repeated except that the polymer 5 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 5 and the compound of Formula A (ITIC) was spin-coated at 1800 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  5-3. Manufacture of organic solar cell

The procedure of Example 1-1 was repeated except that the polymer 5 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 5 and the compound of Formula A (ITIC) was spin-coated at 2100 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  5-4. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 5 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 5 and the compound of Formula A (ITIC) was spin-coated at 2400 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  6-1. Manufacture of organic solar cell

The procedure of Example 1-1 was repeated except that the polymer 6 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 6 and the compound of Formula A (ITIC) was spin-coated at 1500 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  6-2. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 6 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 6 and the compound of Formula A (ITIC) was spin-coated at 1800 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  6-3. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 6 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 6 and the compound of Formula A (ITIC) was spin-coated at 2100 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  6-4. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the above polymer 6 was used instead of the polymer 2 in Example 1-1, and the complex solution of the polymer 6 and the above-mentioned formula A (ITIC) was spin-coated at 2400 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  7-1. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 7 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 7 and the compound of Formula A (ITIC) was spin-coated at 1200 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  7-2. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 7 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 7 and the compound of Formula A (ITIC) was spin-coated at 1500 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  7-3. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 7 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 7 and the polymeric compound A (ITIC) was spin-coated at 1800 rpm instead of 1700 rpm Organic solar cells were prepared.

Example  7-4. Manufacture of organic solar cell

The same procedure as in Example 1-1 was repeated except that the polymer 7 was used instead of the polymer 2 in Example 1-1 and the complex solution of the polymer 7 and the compound of Formula A (ITIC) was spin-coated at 2100 rpm instead of 1700 rpm Organic solar cells were prepared.

Examples 1-1 to 1-4, 2-1 to 2-4, 3-1 to 3-4, 4-1 to 4-4, 5-1 to 5-4, 6-1 to 6-4 , 7-1 to 7-4 and Comparative Examples 1-1 to 1-4 were measured under the conditions of 100 mW / cm ² (AM 1.5) and the results are shown in Table 8 below. Respectively.

Spin-speed (rpm) V _oc
(V) J _sc
(mA / cm ² ) FF η
(%) Mean η
(%) Example 1-1 1700 0.887 15.608 0.634 8.77 8.87 0.888 15.650 0.645 8.97 Examples 1-2 2100 0.869 16.134 0.655 9.18 9.13 0.887 15.851 0.645 9.07 Example 1-3 2500 0.886 15.984 0.667 9.45 9.39 0.887 15.830 0.664 9.32 Examples 1-4 2900 0.895 15.586 0.647 9.02 9.34 0.890 16.194 0.669 9.65 Comparative Example 1-1 700 0.808 13.579 0.579 6.36 6.30 0.808 13.305 0.579 6.23 Comparative Example 1-2 900 0.803 11.923 0.598 5.73 5.80 0.807 12.306 0.591 5.86 Comparative Example 1-3 1100 0.803 11.723 0.632 5.95 5.85 0.802 11.572 0.618 5.74 Comparative Example 1-4 1300 0.798 12.760 0.643 6.55 6.43 0.795 12.650 0.627 6.31 Example 2-1 1700 0.963 8.433 0.424 3.44 3.40 0.972 8.189 0.421 3.35 Example 2-2 2100 0.965 8.782 0.446 3.78 3.80 0.972 8.628 0.454 3.81 Example 2-3 2500 0.974 8.632 0.460 3.87 3.87 0.980 8.493 0.465 3.87 Examples 2-4 2900 0.964 8.577 0.453 3.75 3.78 0.971 8.517 0.460 3.80 Example 3-1 1700 0.994 6.901 0.424 2.91 2.90 0.999 6.825 0.423 2.89 Example 3-2 2100 0.972 7.283 0.445 3.15 3.14 0.984 7.066 0.448 3.12 Example 3-3 2500 0.993 7.385 0.461 3.38 3.33 0.995 7.133 0.462 3.28 Example 3-4 2900 0.977 7.097 0.432 3.00 3.09 0.979 7.290 0.446 3.18 Example 4-1 1500 0.910 10.47 0.14 1.31 1.31 Example 4-2 1800 0.986 10.74 0.47 4.97 5.05 0.979 10.93 0.48 5.13 Example 4-3 2100 0.950 10.81 0.48 4.93 4.93 Example 4-4 2400 0.984 10.45 0.48 4.89 4.22 0.810 9.77 0.45 3.55 Example 5-1 1500 0.981 12.44 0.47 5.77 5.70 0.977 12.20 0.47 5.64 Example 5-2 1800 0.985 12.80 0.50 6.30 6.30 Example 5-3 2100 0.984 12.57 0.51 6.29 6.20 0.981 12.03 0.52 6.12 Examples 5-4 2400 0.952 11.94 0.45 5.10 5.10 Example 6-1 1500 1.017 9.30 0.37 3.47 3.46 0.875 9.70 0.41 3.46 Example 6-2 1800 1.022 9.90 0.38 3.86 3.83 1.013 9.73 0.39 3.81 Example 6-3 2100 1.026 9.32 0.38 3.64 3.64 Example 6-4 2400 0.918 9.44 0.44 3.82 3.82 Example 7-1 1200 1.036 6.37 0.46 3.06 2.86 1.027 5.97 0.43 2.65 Example 7-2 1500 1.041 7.25 0.48 3.62 3.62 Example 7-3 1800 0.993 7.19 0.49 3.47 3.48 1.032 7.22 0.47 3.49 Example 7-4 2100 1.037 7.32 0.47 3.57 3.23 1.011 6.65 0.43 2.90

Examples 1-1 to 1-4, 2-1 to 2-4, and 3-1 to 2-1-4 using a non-fullerene-based compound as an electron-opening polymer and an electron acceptor according to an embodiment of the present invention, Organic solar cells of 3-4, 4-1 to 4-4, 5-1 to 5-4, 6-1 to 6-4, and 7-1 to 7-4 were compared using a fullerene compound as an electron acceptor It can be seen that the open-circuit voltage is higher than that of the organic solar cells of Examples 1-1 to 1-4. In particular, it can be seen that the organic solar cells of Examples 1-1 to 1-4 have higher open-circuit voltage, higher device efficiency such as charge rate, and higher energy conversion efficiency than Comparative Examples 1-1 to 1-4.

V _oc is the open-circuit voltage, J _sc is the short-circuit current, FF is the fill factor, and? Is the energy conversion efficiency. The open-circuit voltage and the short-circuit current are the X-axis and Y-axis intercepts in the fourth quadrant of the voltage-current density curve, respectively. The higher the two values, the higher the efficiency of the solar cell. The fill factor is the width of the rectangle that can be drawn inside the curve divided by the product of the short-circuit current and the open-circuit voltage. The energy conversion efficiency can be obtained by dividing these three values by the intensity of the irradiated light, and a higher value is preferable.

101: anode (ITO)
102: Hole transport layer (PEDOT: PSS)
103: photoactive layer
104: cathode (Al)

Claims (14)

A first electrode;
A second electrode facing the first electrode; And
And at least one organic layer disposed between the first electrode and the second electrode and including a photoactive layer,
Wherein the photoactive layer comprises an electron donor and an electron acceptor,
Wherein the electron donor comprises a first unit represented by the following general formula (1); And a second unit represented by the following formula (2) or (3)
Wherein the electron acceptor comprises a non-fullerene-based compound.
[Chemical Formula 1]

(2)

(3)

In the above Formulas 1 to 3,
X 1 and X 2 are the same or different and each independently represents a substituted or unsubstituted monocyclic or polycyclic heteroaryl group; Or a substituted or unsubstituted monocyclic or polycyclic aryl group,
Y1 to Y10 are the same or different and are each independently S or Se,
R1 to R12 are the same or different from each other, and each independently hydrogen; Or a substituted or unsubstituted straight or branched alkyl group,
a1, a2, a3 and a4 are each 1 or 2,
When a1, a2, a3 and a4 are each 2, the structures in the two parentheses are equal to or different from each other. The organic solar battery according to claim 1, wherein the non-fullerene-based compound is represented by the following formula (A):
(A)

The organic solar cell according to claim 1, wherein the electron donor and the electron receiver constitute bulk heterojunction (BHJ). The organic solar cell according to claim 1, wherein the compound represented by Formula 1 is represented by Formula 1-1:
[Formula 1-1]

In Formula 1-1,
The definitions of R1, R2, X1 and X2 are the same as those defined in the above formula (1). The organic solar battery according to claim 1, wherein the formula (2) is represented by the following formula (2-1):
[Formula 2-1]

In Formula 2-1,
The definitions of R3 to R8, a1 and a2 are the same as defined in the above formula (2). The organic solar battery according to claim 1, wherein the formula (3) is represented by the following formula (3-1):
[Formula 3-1]

In Formula 3-1,
The definition of R7 to R12, a3 and a4 is the same as defined in the above formula (3). [2] The compound according to claim 1, wherein X1 and X2 are the same or different from each other and each independently is a thioalkoxy group or a thiophene group substituted with a silyl group; A benzothiophene group substituted with an alkyl group; Or a phenyl group substituted with an alkoxy group. The polymer of claim 1, wherein X1 and X2 are the same or different from each other and each independently selected from the following structures:

In the above structure,
R101, R103 to R105, R107 and R109, which are the same or different, are each independently a linear or branched alkyl group,
R102, R106, R108 and R110 are hydrogen,
r102 and r106 are each 1 or 2, r108 and r110 are each an integer of 1 to 4,

Is a moiety bonded to the formula (1). The organic solar cell according to claim 1, wherein the polymer comprises a unit represented by the following formula (4) or (5):
[Chemical Formula 4]

[Chemical Formula 5]

In the above formulas (4) and (5)
l is a molar fraction, 0 < l < 1,
m is a molar fraction, 0 < m < 1,
l + m = 1,
A is a first unit represented by the above formula (1)
B is a second unit represented by the above formula (2) or (3)
n is the number of repeating units, and is an integer of 1 to 10,000. The organic solar battery according to claim 1, wherein the polymer comprises units represented by any one of the following formulas (4-1), (4-2), (5-1)
[Formula 4-1]

[Formula 4-2]

[Formula 5-1]

[Formula 5-2]

In Formulas (4-1), (4-2), (5-1) and (5-2)
The definitions of R1, R2, X1 and X2 are the same as defined in Formula 1,
The definitions of R3 to R8, a1 and a2 are the same as defined in the above formula (2)
R9 to R12, a3 and a4 are the same as defined in the above formula (3)
l is a molar fraction, 0 < l < 1,
m is a molar fraction, 0 < m < 1,
l + m = 1,
n is the number of repeating units, and is an integer of 1 to 10,000. The organic solar battery according to claim 1, wherein the polymer comprises units represented by any one of the following Chemical Formulas 4-1-1 to 4-1-3 and 4-2-1 to 4-2-4:
[Formula 4-1-1]

[Formula 4-1-2]

[Formula 4-1-3]

[Formula 4-2-1]

[Formula 4-2-2]

[Formula 4-2-3]

[Chemical Formula 4-2-4]

In Formulas 4-1-1 to 4-1-3 and 4-2-1 to 4-2-4,
n is the number of repeating units, and is an integer of 1 to 10,000. The organic solar cell according to claim 1, wherein the polymer is a random polymer. The organic solar cell according to claim 1, wherein the number average molecular weight of the polymer is 5,000 g / mol to 1,000,000 g / mol. The organic solar cell according to claim 1, wherein the molecular weight distribution of the polymer is 1 to 10. [

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