KR101719028B1 - Organic solar cell and method for manufacturing the same - Google Patents

Abstract

The present disclosure relates to organic solar cells.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic solar cell and a method of manufacturing the same.

The present invention relates to an organic solar cell and a method of manufacturing the same.

According to the NREL Energy Review, US National Laboratories are currently using oil, coal and gas. This amounts to 80% of the total energy source used. However, current petroleum and coal energy depletion is becoming a major problem, and increasing emissions of carbon dioxide and other greenhouse gases into the air are becoming increasingly serious. On the contrary, the use of renewable energy, which is pollution-free green energy, is still only about 2% of the total energy source. Therefore, the problems for solving the problems of the energy sources are becoming an opportunity to spur more research on the development of renewable energy. Among the renewable energy sources such as wind, water, and sun, solar energy is the most interested. Solar cells using solar energy are expected to be an energy source capable of solving future energy problems because of their low pollution, their infinite resources and their semi-permanent life span.

Solar cells are devices that can convert solar energy directly into electrical energy by applying a 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 terms of economic efficiency and supply / demand of materials, organic solar cells, which are easy to process, have low cost and various functions, are attracting attention as long-term alternative energy sources.

The initial organic solar cell was led by UCSB's Heeger professor group to lead the technology development. Organic solar cells have the advantages of easy, fast, low-cost, and large-area processing of monomolecular organic materials or polymer materials.

However, up to now, organic solar cells still have a low energy conversion efficiency. Therefore, in order to secure competitiveness with other solar cells at present, it is very important to improve the efficiency.

Two-layer organic photovoltaic cells (C. W. Tang, Appl. Phys. Lett., 48, 183. (1996) Efficiencies via Network of Internal Donor-Acceptor Heterojunctions (G. Yu, J. Gao, J. C. Hummelen, F. Wudl, A. J. Heeger, Science, 270, 1789. (1995)

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

The first electrode of the present specification; A second electrode facing the first electrode; A photoactive layer disposed between the first electrode and the second electrode; An electron transport layer provided between the photoactive layer and the first electrode; A hole transport layer provided between the photoactive layer and the second electrode; And an organic material layer including a fullerene derivative provided between the photoactive layer and the electron transporting layer. The present invention also provides an organic solar cell having an inverted structure.

The present disclosure also provides a method of manufacturing a semiconductor device, comprising: preparing a substrate; Forming a first electrode on the substrate; Forming an electron transport layer on the first electrode; Forming an organic material layer including a fullerene derivative on the electron transporting layer; Forming a photoactive layer on the organic material layer including the fullerene derivative; Forming a hole transport layer on the photoactive layer; And forming a second electrode on the hole transport layer. The present invention also provides a method of manufacturing an organic solar battery.

An organic solar cell including an organic material layer including a fullerene derivative according to the present invention has an excellent electron transferring capability and can realize an increase in optical short-circuit current density (Jsc) and an increase in efficiency.

Further, an organic solar cell including an organic material layer including a fullerene derivative is provided between the photoactive layer and the electron transporting layer to improve contact between the photoactive layer and the electron transporting layer, thereby improving the fill factor (FF) Can be implemented.

In addition, the organic solar cell according to one embodiment of the present disclosure can shorten the production cost and / or the efficiency of the process owing to the simple manufacturing process.

The organic solar cell according to one embodiment of the present invention can be a wound structure, and when it is cylindrical, efficiency can be increased by efficiently absorbing light in various directions.

1 shows an organic solar cell according to one embodiment.
2 shows a conventional organic solar cell.
FIG. 3 is a graph of current density-voltage (JV) characteristics of an embodiment and a comparative example according to the present invention.

Brief Description of the Drawings The advantages and features of the present application, and how to accomplish them, will be apparent with reference to the embodiments described below in conjunction with the accompanying drawings. It should be understood, however, that the present application is not limited to the illustrated embodiments but is to be accorded the widest scope consistent with the teachings of the present application. To fully disclose the scope of the invention to those skilled in the art, and this application is only defined by the scope of the claims. The dimensions and relative sizes of the components shown in the figures may be exaggerated for clarity of description.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this application belongs. In addition, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

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

One embodiment of the present disclosure includes a first electrode; A second electrode facing the first electrode; A photoactive layer disposed between the first electrode and the second electrode; An electron transport layer provided between the photoactive layer and the first electrode; A hole transport layer provided between the photoactive layer and the second electrode; And an organic material layer including a fullerene derivative provided between the photoactive layer and the electron transporting layer. The present invention also provides an organic solar cell having an inverted structure.

An embodiment of the organic solar cell of the present specification is shown in Fig.

In one embodiment of the present disclosure, the first electrode may be a cathode.

In one embodiment of the present disclosure, the second electrode may be an anode.

The first electrode in the present specification may be a cathode electrode, and may be a transparent conductive oxide layer or a metal electrode.

When the electrode of the present invention is a transparent conductive oxide layer, the electrode may be formed of a material selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyperopylene (PP), polyimide (PI), polycarbornate conductive material such as plastics such as polystyrene, polyoxymethylene (POM), acrylonitrile styrene copolymer (ABS), acrylonitrile butadiene styrene copolymer and TAC (triacetyl cellulose) Materials doped may be used. Specifically, a metal oxide such as ITO (indium tin oxide), fluorine doped tin oxide (FTO), aluminum doped zink oxide (AZO), IZO (indium zink oxide), ZnO-Ga ₂ O ₃ , ZnO-Al ₂ O ₃ and ATO (antimony tin oxide), and more specifically ITO.

In one embodiment of the present invention, the second electrode may be an anode, and the second electrode may be a metal electrode. Specifically, the metal electrode may be formed of a metal such as silver (Ag), aluminum (Al), platinum (Pt), tungsten (W), copper (Cu), molybdenum (Mo), gold (Au), nickel (Ni) ) Or a combination thereof. More specifically, the metal electrode may be silver (Ag).

In one embodiment of the present invention, the step of forming the first electrode and / or the second electrode comprises sequentially cleaning the patterned ITO substrate with a detergent, acetone, and isopropanol (IPA) To 250 ° C for 1 to 30 minutes, specifically at 250 ° C for 10 minutes, and the surface of the substrate can be modified to be hydrophilic when the substrate is completely cleaned. Pre-treatment techniques for this 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) using oxygen radicals generated by the plasma And a method of oxidizing it by the above method can be used. Through the surface modification as described above, the junction surface potential can be maintained at a level suitable for the surface potential of the hole injection layer, the formation of the polymer thin film on the ITO substrate is facilitated, and the quality of the thin film can be improved. It is possible to select one of the above methods depending on the state of the substrate. Regardless of which method is used, a substantial effect of the pretreatment can be expected in order to prevent oxygen escape from the surface of the substrate and to keep moisture and organic matter as much as possible.

In an embodiment of the present invention described below, a method of oxidizing the surface through ozone generated using UV is used. After the ultrasonic cleaning, the patterned ITO substrate is baked on a hot plate, The next chamber is filled with the UV lamp, and the ITO substrate patterned by the ozone generated by the reaction of the oxygen gas with the UV light is cleaned. However, the method for modifying the surface of the patterned ITO substrate in the present invention is not particularly limited, and any method may be used as long as it is a method for oxidizing the substrate.

In one embodiment of the present invention, the organic solar cell is an inverted structure.

The organic solar cell having the reverse structure in this specification may mean that the anode and the cathode of the organic solar cell having a general structure are formed in the reverse direction. The Al layer used in organic solar cells of general structure is very vulnerable to oxidation reaction in the air and is difficult to be inked, so there is a limitation in commercialization through a printing process. However, since the organic solar cell of the above-described reverse structure can use Ag instead of Al, it is more stable than an organic solar cell having a general structure and is easy to produce Ag ink because it is stable in oxidation reaction. .

Further, it is easy to laminate the organic material layer including the fullerene derivative on the electron transporting layer by chemical bonding.

The electron transport layer in this specification may be a cathode buffer layer.

In one embodiment of the present invention, the electron transporting layer is selected from the group consisting of a conductive oxide and a metal or a combination thereof.

According to one embodiment of the present invention, the conductive oxide of the electron transport layer may be electron-extracting metal oxides, and specifically titanium oxide (TiO _x ); Zinc oxide (ZnO); And cesium carbonate (Cs ₂ CO ₃ ).

According to one embodiment of the present invention, the metal may be a core shell including a metal oxide such as Ag nanoparticle, Ag nanoparticle, Ag-SiO ₂ , Ag-TiO ₂ , or Au-TiO ₂ core shell material. And the core-shell material comprises a metal core and a metal oxide such as _{Ag-SiO 2, Ag-TiO} 2, Au-TiO 2 as a shell.

The organic solar cell according to one embodiment of the present invention includes an electron transporting layer, enhances the efficiency, and chemically bonds with the organic layer including the fullerene derivative, thereby enhancing the stability of the device.

The electron transport layer may be formed on one side of the first electrode using a sputtering method, an E-beam method, a thermal evaporation method, a spin coating method, a screen printing method, an inkjet printing method, a doctor blade method or a gravure printing method, have.

In one embodiment of the present invention, the organic material layer including the fullerene derivative is a carboxyl group; A hydroxy group; Or a fullerene derivative in which a carboxy group and a hydroxy group are simultaneously substituted.

In one embodiment of the present invention, the organic material layer containing the fullerene derivative includes a fullerene derivative substituted with a carboxyl group.

A fullerene derivative substituted with a carboxyl group and / or a hydroxy group according to an embodiment of the present invention is capable of chemical bonding with electron-extracting metal oxides contained in an electron transport layer. Therefore, the organic material layer including the fullerene derivative provided between the photoactive layer and the electron transporting layer improves the contact force between the photoactive layer and the electron transporting layer. In addition, the organic material layer including the fullerene derivative may include a fullerene derivative having an excellent electron accepting ability to improve the electron transferring ability from the photoactive layer to the electron transporting layer.

Further, the organic material layer including the fullerene derivative is provided between the photoactive layer and the electron transporting layer, thereby lowering the energy barrier between the photoactive layer and the electron transporting layer. Therefore, one embodiment of the present invention can provide a high efficiency organic solar cell.

In one embodiment of the present invention, the electron transport layer and the organic material layer including the fullerene derivative are in contact with each other.

In another embodiment, the electron transport layer and the organic material layer including the fullerene derivative are chemically bonded to each other.

The organic material layer containing the fullerene derivative may be chemically bonded by dispersing the fullerene derivative in water or alcohol and then adsorbing the fullerene derivative in the electron transporting layer.

Specifically, the hydrogen of the hydroxyl group or the carboxyl group of the fullerene derivative is combined with the hydroxyl group of the water or the alcohol, and the fullerene derivative and the electron transporting layer form a covalent bond by dehydration. For example, it may be a structure of a metal oxide -O- (O =) C-fullerene in an electron transporting layer.

In one embodiment of the present invention, a chemical bond is formed at the interface between the interface of the electron transporting layer and the organic material layer including the fullerene derivative. In this case, it is excellent in physical and / or thermal stability, and an excellent effect can be obtained in the lifetime of the device.

In one embodiment of the present invention, the organic material layer including the fullerene derivative includes only a fullerene derivative.

In one embodiment of the present invention, the fullerene derivative is represented by any one of the following formulas (1) to (4).

[Chemical Formula 1]

(2)

(3)

[Chemical Formula 4]

In formulas (1) to (4)

n is an integer of 1 to 10,

When n is 2 or more, the structures in parentheses are the same or different,

Cn is a C ₆₀ to C ₁₂₀ fullerene,

a, b, c and d are each an integer of 1 to 4,

When a is 2 or more, L1 is the same or different from each other,

When b is 2 or more, L2 is the same or different from each other,

When c is 2 or more, L 3 are the same or different from each other,

When d is 2 or more, L 4 are the same or different from each other,

L1 to L4 are the same or different and each independently represents a substituted or unsubstituted alkylene group; A substituted or unsubstituted alkenylene group; A substituted or unsubstituted arylene group; Or a divalent substituted or unsubstituted heterocyclic group containing at least one of N, O and S atoms,

R1 and R2 are the same or different from each other, and each independently hydrogen; heavy hydrogen; A halogen group; A nitro group; A nitrile group; Imide; Amide group; A hydroxy group; Ester group; A carbonyl group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted arylalkyl 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 alkylamine group; A substituted or unsubstituted aralkylamine group; A substituted or unsubstituted arylamine group; A substituted or unsubstituted heteroarylamine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heterocyclic group containing at least one of N, O and S atoms.

The structure in the parentheses can be bonded to the carbon atom constituting the fullerene skeleton of the fullerene derivative, and the position is not limited if it is a bondable site.

In the present specification, the structure is not limited as long as it is a fullerene derivative substituted with a carboxyl group and / or a hydroxy group. The structure connecting the fullerene derivative and the carboxyl group and / or the hydroxy group may be a single bond as shown in the above formulas (1) and (2), and may form a triangular ring as shown in the following formulas (3) and (4). In addition, it may include, but is not limited to, quadrangular to octagonal rings.

,

,

,

,

등의 구조일 수 있으며, 이를 한정하지 않는다. In this specification, the triangular ring

,

,

,

,

And the like, but it is not limited thereto.

In the above structure, * denotes a carbon atom of the fullerene derivative.

In one embodiment of the present disclosure, L1 to L4 include a double bond. In one embodiment of the present specification, L1 to L4 include a conjugated structure.

In this case, the electron transporting ability to receive electrons from the electron transporting layer and transfer them to the fullerene derivative can be enhanced.

Specifically, in one embodiment, L1 to L4 are the same or different and each independently represents a substituted or unsubstituted alkenylene group; A substituted or unsubstituted arylene group; Or a divalent substituted or unsubstituted heterocyclic group containing at least one of N, O and S atoms.

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

As used herein, the term " substituted or unsubstituted " A halogen group; An alkyl group; An alkenyl group; An alkoxy group; Ester group; A carbonyl group; A carboxyl group; A hydroxy group; A cycloalkyl group; Silyl group; An arylalkenyl group; An aryloxy group; An alkyloxy group; An alkylsulfoxy group; Arylsulfoxy group; Boron group; An alkylamine group; An aralkylamine group; An arylamine group; A heteroaryl group; Carbazole group; An arylamine group; An aryl group; A nitrile group; A nitro group; A hydroxy group; And a heterocyclic group containing at least one of N, O and S atoms, or does not have any substituent (s).

In the present specification, the halogen group may be fluorine, chlorine, bromine or iodine.

In the present specification, the number of carbon atoms of the imide group is not particularly limited, but is preferably 1 to 25 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 by nitrogen of the amide group with hydrogen, a straight-chain, branched-chain or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 25 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, the ester group may be substituted with a straight-chain, branched or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 25 carbon atoms in the ester group. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

로 표시될 수 있다. In the present specification, a carbonyl group is

. ≪ / RTI >

R is hydrogen; A substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; A substituted or unsubstituted cycloalkyl group having 3 to 60 carbon atoms; A substituted or unsubstituted arylalkyl group having 7 to 50 carbon atoms; A substituted or unsubstituted aryl group having 6 to 60 carbon atoms; Or a substituted or unsubstituted heterocyclic group having 2 to 60 carbon atoms containing at least one of N, O and S atoms.

또는

로 표시될 수 있다. R 및R'는 서로 동일하거나 상이하고, 수소; 탄소수 1 내지 25의 직쇄, 분지쇄 또는 고리쇄의 치환 또는 비치환된 알킬기; 또는 탄소수 6 내지 25의 치환 또는 비치환된 아릴기이다. In the present specification,

or

. ≪ / RTI > R and R 'are the same or different from each other and represent hydrogen; A straight, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 25 carbon atoms; Or a substituted or unsubstituted aryl group having 6 to 25 carbon atoms.

로 표시될 수 있다. R은 탄소수 1 내지 25의 직쇄, 분지쇄 또는 고리쇄의 치환 또는 비치환된 알킬기; 또는 탄소수 6 내지 25의 치환 또는 비치환된 아릴기이다. 구체적으로 Z1 내지 Z3는 서로 동일하거나 상이하고, 탄소수 6 내지 25의 직쇄, 분지쇄 또는 고리쇄의 치환 또는 비치환된 알킬기; 또는 탄소수 6 내지 25의 치환 또는 비치환된 아릴기이다. In the present specification, the ether group

. ≪ / RTI > R is a linear, branched or cyclic substituted or unsubstituted alkyl group having 1 to 25 carbon atoms; Or a substituted or unsubstituted aryl group having 6 to 25 carbon atoms. Specifically, Z 1 to Z 3 are the same or different and each is a linear, branched or cyclic substituted or unsubstituted alkyl group having 6 to 25 carbon atoms; Or a substituted or unsubstituted aryl group having 6 to 25 carbon atoms.

In one embodiment of the present invention, the ether group is an alkyl ether group.

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, N-octyl, 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. Specific examples thereof include cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, 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 number of carbon atoms of the arylalkyl group is not particularly limited, but in one embodiment of the present specification, the arylalkyl group has 7 to 50 carbon atoms. Specifically, the aryl moiety has 6 to 49 carbon atoms and the alkyl moiety has 1 to 44 carbon atoms. Specific examples thereof include benzyl group, p-methylbenzyl group, m-methylbenzyl group, p-ethylbenzyl group, m-ethylbenzyl group, 3,5-dimethylbenzyl group, Group, an?,? -Methylphenylbenzyl group, a 1-naphthylbenzyl group, a 2-naphthylbenzyl group, a p-fluorobenzyl group, a 3,5-difluorobenzyl group, , p-methoxybenzyl group, m-methoxybenzyl group,? -phenoxybenzyl group,? -benzyloxybenzyl group, naphthylmethyl group, naphthylethyl group, naphthylisopropyl group, pyrrolylmethyl group, But are not limited to, an ethyl group, an aminobenzyl group, a nitrobenzyl group, a cyanobenzyl group, a 1-hydroxy-2-phenylisopropyl group, a 1-chloro-2-phenylisopropyl group and the like.

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, the silyl group specifically includes a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, But are not limited thereto.

In the present specification, the aryl group may be monocyclic, and the number of carbon atoms is not particularly limited, but is preferably 6 to 60 carbon atoms. Specific examples of the aryl group include monocyclic aromatic and naphthyl groups such as phenyl group, biphenyl group, triphenyl group, terphenyl group and stilbene group, anthracenyl group, phenanthrenyl group, pyrenyl group, perylenyl group, tetracenyl group, A cyclic aromatic group such as a fluorenyl group, an acenaphthacenyl group, a triphenylene group, and a fluoranthene group, but is not limited thereto.

In the present specification, the fluorenyl group includes a structure of an open fluorenyl group, wherein the open fluorenyl group is a structure in which one ring compound is disconnected in a structure in which two ring organic compounds are connected via one atom.

,

,

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 or heteroaryl group is a hetero ring group containing at least one of O, N and S as a heteroatom, and the number of carbon atoms 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 triazine group, , A quinolinyl group, an isoquinoline group, an indole group, a carbazole group, a benzoxazole group, a benzoimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuranyl group, (phenanthroline), dibenzofuranyl group, and the like, but are not limited thereto.

In the present specification, the heteroaryl in the heteroaryloxy group may be selected from the examples of the above-mentioned heteroaryl group. In the present specification, the aryl group in the aryloxy group, the arylthioxy group, the arylsulfoxy group and the aralkylamine 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. However, the present invention is not limited thereto.

In the present specification, the alkyl group in the alkylthio group, alkylsulfoxy group, alkylamine group, and aralkylamine 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 number of carbon atoms of the amine group is not particularly limited, but is preferably 1 to 30. Specific examples of the amine group include a methylamine group, a dimethylamine group, an ethylamine group, a diethylamine group, a phenylamine group, a naphthylamine group, a biphenylamine group, an anthracenylamine group, a 9- , A diphenylamine group, a phenylnaphthylamine group, a ditolylamine group, a phenyltolylamine group, a triphenylamine group, and the like, but are not limited thereto.

In the present specification, examples of the arylamine group include a substituted or unsubstituted monoarylamine group, a substituted or unsubstituted diarylamine group, or a substituted or unsubstituted triarylamine group. The aryl group in the arylamine group may be a monocyclic aryl group or a polycyclic aryl group. The arylamine group having at least two aryl groups may contain a monocyclic aryl group, a polycyclic aryl group, or a monocyclic aryl group and a polycyclic aryl group at the same time.

Specific examples of the arylamine group include phenylamine, naphthylamine, biphenylamine, anthracenylamine, 3-methylphenylamine, 4-methyl-naphthylamine, 2-methyl- But are not limited to, cenylamine, diphenylamine, phenylnaphthylamine, ditolylamine, phenyltolylamine, carbazole and triphenylamine groups.

In the present specification, the heteroaryl group in the heteroarylamine group can be selected from the examples of the above-mentioned heterocyclic group.

In the present specification, an alkylene group and an arylene group each mean an alkyl group or an aryl group having two bonding positions, that is, a divalent group. 2, the description of the alkyl and aryl groups described above may be applied.

In an embodiment of the present disclosure, the photoactive layer is a photoactive material, including an electron donor material and an electron acceptor material. In this specification, the photoactive material may mean the electron donor material and the electron acceptor material.

In the photoactive layer, the electron donor material forms excitons paired with electrons and holes by photoexcitation, and the excitons are separated into electrons and holes at the interface of the electron donor / electron acceptor. The separated electrons and holes move to the electron donor material and the electron acceptor material, respectively, and they are collected in the first electrode and the second electrode, respectively, so that they can be used as electric energy from the outside.

 Further, in one embodiment of the present specification, the photoactive layer may be a bulk heterojunction structure or a double layer junction structure. The bulk heterojunction structure may be a bulk heterojunction (BHJ) junction type, and the bilayer junction structure may be a bi-layer junction type.

In one embodiment of the present disclosure, the mass ratio of the electron donor material and the electron donor material may be from 1:10 to 10: 1. Specifically, the mass ratio of the electron-accepting material to the electron-donating material in the present specification may be 1: 0.5 to 1: 5.

According to one embodiment of the present disclosure, the electron donor material comprises at least one electron donor; Or a polymer of at least one electron acceptor and at least one electron donor. The electron donor may include at least one kind of electron donor. Further, the electron donor material includes a polymer of at least one kind of electron acceptor and at least one kind of electron donor.

Specifically, the electron donor may be selected from the group consisting of thiophene, fluorene, carbazole, etc. based on MEH-PPV (poly [2-methoxy-5- (2'-ethyl-hexyloxy) Of various polymeric and monomolecular materials.

Specifically, the monomolecular material is selected from the group consisting of copper (II) phthalocyanine, zinc phthalocyanine, tris [4- (5-decynomethylidene methyl- Amine (tris [4- (5-dicyanomethylidenemethyl-2-thienyl) phenyl] amine, 2,4-bis [4- (N, N- dibenzylamino) -2,6-dihydroxyphenyl] (2,4-bis [4- (N, N-dibenzylamino) -2,6-dihydroxyphenyl] squaraine, benz [b] anthracene, and pentacene. ≪ / RTI >

Specifically, the polymer material may be poly-3-hexyl thiophene (P3HT), poly [N-9'-heptadecanyl-2,7-carbazole- 2 ', 3'-benzothiadiazole)], PCPDTBT (poly [2,6- (4,4-bis- (2, ethylhexyl) -4H-cyclopenta [ 1-b, 3,4-b '] dithiophene) -tallow-4,7- (2,1,3-benxothiadiazole)], PFO-DBT (poly [2,7- (9,9- ) -tallow-5,5- (4,7-di2-thienyl-2,1,3-benzothiadiazole)], PTB7 (Poly [[4,8-bis [(2-ethylhexyl) oxy] benzo [ , 2-b: 4,5-b '] dithiophene-2,6-diyl] [3-fluoro-2- (2-ethylhexyl) carbonyl] thieno [3,4- b] thiophenediyl] DBT (Poly [2,7- (9,9-dioctyl-dibenzosilole) -alt-4,7-bis (thiophen-2-yl) benzo-2,1,3-thiadiazole] Or more species.

In one embodiment of the present invention, the electron accepting material may be a fullerene derivative or a non-fullerene derivative.

In one embodiment of the present specification, the fullerene derivative is a fullerene derivative of C60 to C90. Specifically, the fullerene derivative may be a C60 fullerene derivative or a C70 fullerene derivative.

According to one embodiment of the present disclosure, the C60 fullerene derivative or the C70 fullerene derivative is independently selected from the group consisting of hydrogen; heavy hydrogen; 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 alkylamine group; A substituted or unsubstituted aralkylamine group; A substituted or unsubstituted arylamine group; A substituted or unsubstituted heteroarylamine group; A substituted or unsubstituted aryl group; And a substituted or unsubstituted heterocyclic group containing at least one of N, O and S atoms, or two adjacent substituents may be further substituted with a substituent forming a condensed ring.

In one embodiment of the present invention, the fullerene derivative may be selected from the group consisting of a C76 fullerene derivative, a C78 fullerene derivative, a C84 fullerene derivative, and a C90 fullerene derivative.

In one embodiment of the present invention, the C76 fullerene derivative, the C78 fullerene derivative, the C84 fullerene derivative, and the C90 fullerene derivative are each independently selected from the group consisting of hydrogen; heavy hydrogen; 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 alkylamine group; A substituted or unsubstituted aralkylamine group; A substituted or unsubstituted arylamine group; A substituted or unsubstituted heteroarylamine group; A substituted or unsubstituted aryl group; And a substituted or unsubstituted heterocyclic group containing at least one of N, O and S atoms, or two adjacent substituents may be further substituted with a substituent forming a condensed ring.

The fullerene derivative has an ability to separate excitons (electron-hole pairs) and an excellent charge mobility as compared with the non-fullerene derivative, which is advantageous for the efficiency characteristics.

The photoactive layer according to one embodiment of the present disclosure may form bulk heterojunction (BHJ) with the electron donor material and the electron acceptor material. The photoactive layer may be annealed at 30 ° C to 300 ° C for 1 second to 24 hours to maximize the characteristics after the electron donor and electron donor materials are mixed.

In one embodiment of this disclosure, the optically active layer is poly 3-hexyl thiophene [P3HT: poly 3-hexyl thiophene ] to the electron donor material, and [6,6] -phenyl -C ₆₁ - butyric acid methyl ester (PC ₆₁ BM) and / or [6,6] -phenyl-C ₇₁ -butyric acid methyl ester (PC ₇₁ BM) as electron acceptor materials.

In one aspect of the present invention, the mass ratio of the electron donor material and the electron donor material may be 1: 0.4 to 1: 2, and specifically 1: 0.7. However, the photoactive layer is not limited to the above materials.

The photoactive material is dissolved in an organic solvent, and then the photoactive layer is introduced into the solution at a thickness ranging from 50 nm to 280 nm by spin coating or the like. At this time, dip coating, screen printing, spray coating, doctor blade, brush painting and the like can be applied to the photoactive layer.

The electron acceptor may include other fullerene derivatives such as C70, C76, C78, C80, C82, and C84, including PC ₆₁ BM. The coated thin film may be heat treated at 80 to 160 ° C to form crystals of the conductive polymer It is good to raise the castle. Specifically, the organic solar cell of the present invention has an inverted structure, and in this case, annealing pre-annealing can be performed at 120 ° C.

In one embodiment of the present invention, the organic solar cell further comprises one or more organic layers in the group consisting of a hole injecting layer, a hole transporting layer, a hole blocking layer, a charge generating layer, an electron blocking layer, an electron injecting layer and an electron transporting layer .

The hole transporting layer and / or the electron transporting layer material of the present invention may be a material that increases the probability that electrons and holes are efficiently transferred to the electrode by efficiently transferring electrons and holes to the photoactive layer, but is not particularly limited.

The hole transport layer in this specification may be an anode buffer layer.

A hole transport layer may be introduced onto the pre-treated photoactive layer through spin coating, dip coating, inkjet printing, gravure printing, spray coating, doctor blade, bar coating, gravure coating, brush painting, thermal evaporation or the like. In this case, poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate) [PEDOT: PSS] is mainly used as a conductive polymer solution, and hole-extracting metal oxides Molybdenum oxide (MoO _x ), vanadium oxide (V ₂ O ₅ ), nickel oxide (NiO), tungsten oxide (WO _x ), and the like can be used. According to an embodiment of the present invention, the hole transport layer may be formed to a thickness of 5 nm to 10 nm through a thermal deposition system of MoO ₃ .

According to one embodiment of the present disclosure, the organic solar cell may be a wound structure. Specifically, the organic solar cell can be manufactured in the form of a flexible film, and it can be made into a cylindrical solar cell having a winding structure that is hollow. When the organic solar cell is a structure in which the organic solar cell is wound, it can be installed in a manner to stand on the ground. In this case, it is possible to secure a portion where the angle of incidence of light is maximized while the sun at the location where the organic solar cell is installed moves from east to west. Thus, while the sun is floating, it has the advantage of absorbing as much light as possible and increasing efficiency.

One embodiment of the present disclosure provides a method of manufacturing a semiconductor device, comprising: preparing a substrate; Forming a first electrode on the substrate; Forming an electron transport layer on the first electrode; Forming an organic material layer including a fullerene derivative on the electron transporting layer; Forming a photoactive layer on the organic material layer including the fullerene derivative; Forming a hole transport layer on the photoactive layer; And forming a second electrode on the hole transport layer. The present invention also provides a method of manufacturing an organic solar battery.

In one embodiment of the present invention, the organic material layer including the fullerene derivative is a carboxyl group; A hydroxy group; Or a fullerene derivative in which a carboxyl group and a hydroxy group are simultaneously substituted.

In one embodiment of the present invention, the step of dispersing the fullerene derivative in water or alcohol and adsorbing the fullerene derivative in the electron transporting layer may form an organic material layer containing the fullerene derivative.

In one embodiment of the present invention, the fullerene derivative is dispersed in water or an alcohol and is adsorbed on the electron transporting layer. Then, an organic material layer containing a fullerene derivative is formed on the electron transporting layer by chemical bonding, Unfractionated fullerene derivatives can be removed with water or alcohol.

The organic material layer including the fullerene derivative, the first electrode, the second electrode, the photoactive layer, the hole transport layer, the electron transport layer, and the fullerene derivative in the organic solar cell according to one embodiment of the present invention are the same as those described above.

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.

As used herein, the term "phase" does not only mean that it is placed on one layer but may mean that it is positioned on the position. That is, the layers located on any one layer may have other layers in between.

According to an embodiment of the present invention, the step of fabricating the single-layer organic solar cell may further include a step of forming a hole transporting layer and a step of forming an electron transporting layer.

According to an embodiment of the present invention, the step of forming the first electrode may include a step of hydrophilizing the surface after cleaning.

In order to facilitate understanding of the organic solar cell of this specification, the following examples and comparative examples will be described. However, the scope of the present invention is not limited to the examples.

[ Example  One]

(1) Cleaning of patterned ITO substrate

Patterned ITO glass (substrate resistance: ~ 11.5 Ω / sq, Shinan SNP) In order to clean the surface of the substrate, ultrasonic cleaning was performed for 20 minutes each using a cleaning agent, acetone, and isopropanol (IPA) After thoroughly blowing, the substrate was dried on a hot plate at 250 ° C for 10 minutes to completely remove moisture. Once the patterned ITO substrate was cleaned, the surface was modified in a UVO scrubber (UVO cleaner, Ahtech LTS, Korea) for 30 minutes.

(2) Preparation of electron transport layer

A ZnO precursor solution is prepared using a hydrolysis reaction in advance and the zinc oxide (ZnO) solution is spin-coated, and then the remaining solvent is removed by heat treatment to form an electron transport layer Completed.

(3) Preparation of an organic material layer containing a fullerene derivative

A fullerene derivative represented by 0.3 mM of the following fullerene 1 was dissolved or dispersed in isopropanol (IPA) to prepare a 0.3 mM solution. The film prepared up to the electron transporting layer was immersed in this solution, and the solvent was allowed to stand in the air for a long time so that the solvent was not volatilized. The film having the fullerene compound adhered to the electron transport layer was taken out again, rinsed in isopropanol, and dried in the air.

[Fullerene 1]

n: 1 to 5

Fullerene: C60 fullerene

(4) Production of photoactive layer

A photoactive layer material obtained by mixing P3HT and PC ₆₁ BM in a weight ratio of 1: 0.7 was dissolved in a chlorobenzene solvent at a concentration of 2 wt%, and spin-coated on the ITO substrate into which the electron transport layer was introduced to form a photoactive layer .

(5) Production of hole transport layer

In the thermal evaporator, MoO ₃ was deposited at a thickness of 5 to 10 nm at a rate of 0.2 Å / s to form a hole transport layer.

(6) Fabrication of reverse-structured organic solar cell

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 ]

An organic solar cell was prepared using the 2 wt% concentration of P3HT and PC ₆₁ BM in the same manner as in Example 1, except that the organic material layer containing the fullerene derivative (3) in Example 1 was prepared.

In order to measure the electrooptical characteristics of the organic solar cells prepared in Example 1 and Comparative Example 1, current-voltage densities were measured under standard conditions (Air mass 1.5 Global, 100 mW / cm ² ) using an ABET solar simulator.

The optical short-circuit current density J _sc , the open-circuit voltage V _oc , the fill factor (FF) and the energy conversion efficiency of the organic solar cells are shown in Table 1 below.

At this time, the fill factor (FF) is the voltage value ( V _max ) × the current density ( J _max ) / ( V _oc × J _sc ) at the maximum power point, the energy conversion efficiency is FF × ( J _sc × V _oc ) / P _in , And P _in = 100 [mW / cm < 2 >].

In Table 1, the comparative example is a measurement of the current-voltage density of an organic solar cell that does not use an organic material layer including a fullerene derivative. In Example 1, an organic material layer containing a fullerene derivative is formed between the electron transporting layer and the photoactive layer It is.

Fullerene J _sc
(mA / cm ² ) V _oc
(V) FF 侶 (%) Example 1 Fullerene 1 10.39 0.634 0.589 3.89 Comparative Example 1 - 9.85 0.620 0.531 3.25

As can be seen from Table 1 and FIG. 3, comparing Example 1 with Comparative Example 1, it can be seen that the optical short-circuit current density and the fill factor increase and the efficiency increases by about 20%. That is, an organic solar cell having a reverse structure including an organic material layer including a fullerene derivative has an improved electron transporting capability and an increased optical short-circuit current density as compared with an organic solar cell containing no organic material layer containing a fullerene derivative, The improvement in contact between the layer and the electron transport layer also increases the fill factor. Accordingly, it can be confirmed that high efficiency can be realized.

[ Example  2]

In the same manner as in Example 1 except that the fullerene derivative represented by the following fullerene 2 was used in place of the fullerene derivative represented by the fullerene 1 in (3) in Example 1, a 2 wt% concentration of P3HT and PC ₆₁ BM To prepare an organic solar cell.

[Fullerene 2]

n: 1 to 5

Fullerene: C60 fullerene

In the case of Example 2, the optical short-circuit current density J _sc is 7.09 mA / cm ² , the optical open-circuit voltage V _oc is 0.208 V, the fill factor (FF) is 0.305 and the energy conversion efficiency is 0.45% Respectively.

Compared with the first comparative example, it can be confirmed that the optical open-circuit voltage is significantly lowered in the second embodiment.

 [ Example  3]

In the same manner as in Example 1 except that the fullerene derivative represented by the following fullerene 3 was used in place of the fullerene derivative represented by the fullerene 1 in (3) in Example 1, a 2 wt% concentration of P3HT and PC ₆₁ BM To prepare an organic solar cell.

[Fullerene 3]

Fullerene: C60 fullerene

In Example 3, the optical short-circuit current density J _sc was 7.89 mA / cm ² , the optical open-circuit voltage V _oc was 0.618 V, the fill factor (FF) was 0.346, and the energy conversion efficiency was 1.68% Respectively.

It can be confirmed that the optical open-circuit voltage is significantly lowered in the third embodiment as compared with the first comparative example.

FIG. 3 is a graph showing current density-voltage (J-V) characteristics of the organic solar cells prepared in Examples 1 to 3 and Comparative Examples.

Although the embodiments of the present invention have been described above, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the present invention. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (12)

A first electrode;
A second electrode facing the first electrode;
A photoactive layer disposed between the first electrode and the second electrode;
An electron transport layer provided between the photoactive layer and the first electrode;
A hole transport layer provided between the photoactive layer and the second electrode; And
And an organic material layer including a fullerene derivative provided between the photoactive layer and the electron transporting layer,
The photoactive layer is formed by forming an electron donor material and an electron acceptor material in a bulk heterojunction (BHJ)
Wherein the fullerene derivative is represented by any one of the following formulas (1) to (4):
[Chemical Formula 1]

(2)

(3)

[Chemical Formula 4]

In formulas (1) to (4)
n is an integer of 1 to 10,
When n is 2 or more, the structures in parentheses are the same or different,
Cn is a C ₆₀ to C ₁₂₀ fullerene,
a, b, c and d are each an integer of 1 to 4,
When a is 2 or more, L1 is the same or different from each other,
When b is 2 or more, L2 is the same or different from each other,
When c is 2 or more, L 3 are the same or different from each other,
When d is 2 or more, L 4 are the same or different from each other,
L1 to L4 are the same or different and each independently an alkylene group or an arylene group,
R1 and R2 are aryl groups. delete delete delete The method according to claim 1,
Wherein the electron transport layer and the organic material layer including the fullerene derivative are in contact with each other. The method according to claim 1,
Wherein the electron transport layer and the organic material layer including the fullerene derivative are chemically bonded to each other. The method according to claim 1,
Wherein the organic material layer including the fullerene derivative includes only a fullerene derivative. The method according to claim 1,
Wherein the electron transport layer comprises one or more selected from the group consisting of a conductive oxide and a metal. The method according to claim 1,
Wherein the electron transporting layer comprises titanium oxide; Zinc oxide; And cesium carbonate. 2. The organic solar cell according to claim 1, The method according to claim 1,
Wherein the organic solar cell further comprises one or more organic layers selected from the group consisting of a hole injecting layer, a hole blocking layer, a charge generating layer, an electron blocking layer, and an electron injecting layer. battery. Preparing a substrate;
Forming a first electrode on the substrate;
Forming an electron transport layer on the first electrode;
Forming an organic material layer including a fullerene derivative on the electron transporting layer;
Forming a photoactive layer on the organic material layer including the fullerene derivative;
Forming a hole transport layer on the photoactive layer; And
And forming a second electrode on the hole transport layer,
The photoactive layer is formed by forming an electron donor material and an electron acceptor material in a bulk heterojunction (BHJ)
Wherein the fullerene derivative is represented by any one of the following Chemical Formulas 1 to 4:
[Chemical Formula 1]

(2)

(3)

[Chemical Formula 4]

In formulas (1) to (4)
n is an integer of 1 to 10,
When n is 2 or more, the structures in parentheses are the same or different,
Cn is a C ₆₀ to C ₁₂₀ fullerene,
a, b, c and d are each an integer of 1 to 4,
When a is 2 or more, L1 is the same or different from each other,
When b is 2 or more, L2 is the same or different from each other,
When c is 2 or more, L 3 are the same or different from each other,
When d is 2 or more, L 4 are the same or different from each other,
L1 to L4 are the same or different and each independently an alkylene group or an arylene group,
R1 and R2 are aryl groups. delete

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