Photoelectric conversion element, electronic device, and power module

Abstract

To provide a photoelectric conversion element with excellent photoelectric conversion efficiency for low-illuminance light.SOLUTION: The photoelectric conversion element has a photoelectric conversion layer containing a polymer material with a structure represented by general formula (1) in the figure. In general formula (1): R1, R2, R3 and R4 represent a C2-20 alkyl group, thioalkyl group or alkoxy group; R1 and R3 differ from each other or R2 and R4 differ from each other; n is an integer of 50 to 1,000 inclusive; and X and Y represent halogen or hydrogen.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a photoelectric conversion element, an electronic device, and a power supply module. [Background technology]

[0002] In recent years, the driving power of electronic circuits has become extremely low, and in preparation for the coming IoT (Internet of Things) society, it has become possible to drive various electronic components such as sensors with even weak power (in the order of μW). Furthermore, when using sensors, there are hopes that they will be applied to energy harvesting elements as independent power sources that can generate and consume electricity on the spot, and among these, photoelectric conversion elements are attracting attention as elements that can generate electricity wherever there is light. There is a growing demand for energy harvesting elements that can generate electricity efficiently using indoor light from fluorescent lamps, LED lamps, etc. However, there are few solar cells that exhibit high photoelectric conversion efficiency under low-illuminance light, and among these, organic thin-film solar cells are known to have little illuminance dependency.

[0003] However, conventional organic thin-film solar cells have been developed mainly for use with sunlight as a light source, and there have been very few reports of materials that have high photoelectric conversion efficiency for low-illuminance light.

[0004] Various kinds of conjugated polymer-based p-type organic semiconductor materials have been developed so far as p-type organic semiconductor materials (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a photoelectric conversion element having excellent photoelectric conversion efficiency for low illuminance light. [Means for solving the problem]

[0006] The photoelectric conversion element of the present invention as a means for solving the above problems is a photoelectric conversion element having a photoelectric conversion layer, The photoelectric conversion layer is characterized in that it contains a polymer material having a structure represented by the following general formula (1) and an N-type semiconductor material. [ka] (In the above general formula (1), R 1 , R 2 , R 3 , and R 4 represents an alkyl group, a thioalkyl group, or an alkoxy group having 2 to 20 carbon atoms; R 1 and R 3 and are different from each other or R 2 and R 4 are different from each other, n is an integer of 50 or more and 1,000 or less, and X and Y are halogen or hydrogen. Effect of the Invention

[0007] According to the present invention, it is possible to provide a photoelectric conversion element having excellent photoelectric conversion efficiency for low illuminance light. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of a photoelectric conversion element according to the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing an example of another layer structure of the photoelectric conversion element according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (Photoelectric conversion element) The photoelectric conversion element includes a substrate, a first electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, and a second electrode, and may further include other members as necessary. In the present invention, the term "photoelectric conversion element" refers to an element that converts light energy into electrical energy or an element that converts electrical energy into light energy, and specific examples thereof include solar cells and photodiodes.

[0010] Hereinafter, a photoelectric conversion element according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, but may be modified, added, modified, deleted, or otherwise altered within the scope of what a person skilled in the art can conceive, and is within the scope of the present invention as long as the functions and effects of the present invention are achieved in any aspect.

[0011] The layered structure of the photoelectric conversion element is not particularly limited and may be appropriately selected depending on the purpose. An example of the layered structure is a layered structure having a substrate 1, a first electrode 2, an electron transport layer 3, a photoelectric conversion layer 4, a hole transport layer 5, and a second electrode 6 in this order as shown in FIG. 1. Also included is a laminated structure having a substrate 1, a first electrode 2, a hole transport layer 5, a photoelectric conversion layer 4, an electron transport layer 3, and a second electrode 6 in this order as shown in FIG.

[0012] <Photoelectric conversion layer> The photoelectric conversion layer contains a polymer material having a structure represented by the following general formula (1) and an N-type semiconductor material, and further contains other components as necessary. [ka] (In the above general formula (1), R 1 , R 2 , R 3 , and R 4 represents an alkyl group, a thioalkyl group, or an alkoxy group having 2 to 20 carbon atoms, and R 1 and R 3 and are different from each other or R 2 and R 4 are different from each other, n is an integer of 50 or more and 1,000 or less, and X and Y are halogen or hydrogen. The photoelectric conversion layer contains a polymer material having a structure represented by the above general formula (1) and an N-type semiconductor material, thereby providing a photoelectric conversion element having excellent photoelectric conversion efficiency for low illuminance light. In the present disclosure, low illuminance refers to, for example, the illuminance in an indoor environment illuminated by lighting or the like, specifically, illuminance of 20 lux or more and 1,000 lux or less, which is very weak compared to direct sunlight (approximately 100,000 lux).

[0013] -Polymer materials- The polymer material has a structure represented by the following general formula (1): The structure represented by the following general formula (1) functions as a P-type semiconductor material when combined with an N-type semiconductor material. It is sufficient that at least one structural unit having the structure represented by the following general formula (1) is contained in the polymer material, and it is preferable that an average of two or more units are contained per polymer chain, and it is more preferable that an average of three or more units are contained per polymer chain. The terminal in the compound having the structure represented by the general formula (1) is not particularly limited as long as it functions as a P-type semiconductor and can be appropriately selected depending on the purpose. Examples of the terminal include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a fluoroalkyl group, a fluoroalkoxy group, an aryl group, an arylamino group, and a monovalent heterocyclic group. [ka] (In the above general formula (1), R 1 , R 2 , R 3 , and R 4 represents an alkyl group, a thioalkyl group, or an alkoxy group having 2 to 20 carbon atoms, and R 1 and R 3 and are different from each other or R 2 and R 4 are different from each other, n is an integer of 50 or more and 1,000 or less, and X and Y are halogen or hydrogen.

[0014] In the general formula (1), R1 , R 2 , R 3 , R 4 is any one of an alkyl group, a thioalkyl group, and an alkoxy group having 2 to 20 carbon atoms. The alkyl group having 2 to 20 carbon atoms is not particularly limited and can be appropriately selected depending on the purpose. Examples of the alkyl group include an ethyl group, a propyl group, a normal propyl group (n-propyl group), a butyl group, a normal butyl group (n-butyl group), a pentyl group, a normal pentyl group (n-pentyl group), a hexyl group, a normal hexyl group (n-hexyl group), a 2-ethylhexyl group, a heptyl group, a normal heptyl group (n-heptyl group), an octyl group, a normal octyl group (n-octyl group), a 2-butyloctyl group, a nonyl group, a normal nonyl group (n-nonyl group), a decyl group, a normal decyl group (n-decyl group), a 2-hexyldecyl group, a dodecyl group, a normal dodecyl group (n-dodecyl group), and a 2-octyldodecyl group. Examples of the thioalkyl group having 2 to 20 carbon atoms include a thioethyl group, a thiopropyl group, a nor-multi-opropyl group (n-thiopropyl group), a thiobutyl group, a nor-multi-obutyl group (n-thiobutyl group), a thiopentyl group, a nor-multi-opentyl group (n-thiopentyl group), a thiohexyl group, a nor-multi-ohexyl group (n-thiohexyl group), a 2-ethylthiohexyl group, a thioheptyl group, a nor-multi-oheptyl group (n-thioheptyl group), a thiooctyl group, a nor-multi-octyl group (n-thiooctyl group), a 2-butylthiooctyl group, a thiononyl group, a nor-multi-ononyl group (n-thiononyl group), a thiodecyl group, a nor-multi-odecyl group (n-thiodecyl group), a 2-hexylthiodecyl group, a thiododecyl group, a nor-multi-ododecyl group (n-thiododecyl group), and a 2-octylthiododecyl group. Examples of the alkoxy group having 2 to 20 carbon atoms include an ethoxy group, a propyloxy group, a normal propyloxy group (n-propyloxy group), a butyloxy group, a normal butyloxy group (n-butyloxy group), a pentyloxy group, a normal pentyloxy group (n-pentyloxy group), a hexyloxy group, a normal hexyloxy group (n-hexyloxy group), a 2-ethylhexyloxy group, a heptyloxy group, a normal heptyloxy group (n-heptyloxy group), an octyloxy group, a normal octyloxy group (n-octyloxy group), a 2-butyloctyloxy group, a nonyloxy group, a normal nonyloxy group (n-nonyloxy group), a decyloxy group, a normal decyloxy group (n-decyloxy group), a 2-hexyldecyloxy group, a dodecyloxy group, a normal dodecyloxy group (n-dodecyloxy group), and a 2-octyldodecyloxy group.

[0015] In the general formula (1), R 1 and R 2 As the alkyl group, an alkyl group having 2 to 8 carbon atoms is preferable, and an ethyl-n-hexyl group is more preferable.

[0016] In the general formula (1), R 3 and R 4 As the alkyl group, an alkyl group having 16 to 20 carbon atoms is preferable, and an n-hexyl-n-decyl group is preferable.

[0017] In the general formula (1), R 1 and R 3 And R 2 and R 4 The difference in the number of carbon atoms in at least one of the above is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 8 or more and 14 or less.

[0018] In the general formula (1), X and Y are halogen or hydrogen, and X is preferably halogen and Y is preferably hydrogen.

[0019] The halogen is not particularly limited and can be appropriately selected depending on the purpose, but fluorine and chlorine are preferred.

[0020] In the general formula (1), n ​​is an integer of 50 or more and 1,000 or less.

[0021] Examples of the polymer material include exemplary compounds 1 to 20 shown in Table 1 below. The terminals of exemplary compounds 1 to 20 are not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a fluoroalkyl group, a fluoroalkoxy group, an aryl group, an arylamino group, and a monovalent heterocyclic group. In the exemplary compounds 1 to 20, n is an integer of 50 or more and 1,000 or less.

[0022] [Table 1]

[0023] The weight average molecular weight (Mw) of the polymer material is not particularly limited and can be appropriately selected according to the purpose, but is preferably 3,000 or more, more preferably 5,000 to 5,000,000, and particularly preferably 100,000 to 2,000,000. When the weight average molecular weight (Mw) is 5,000 or more, it is possible to prevent film defects from occurring in the photoelectric conversion layer to be formed. When the weight average molecular weight (Mw) is 5,000,000 or less, it is possible to increase the solubility in an organic solvent in the photoelectric conversion layer forming solution described below.

[0024] The weight average molecular weight (Mw) is a molecular weight that can be measured by gel permeation chromatography (GPC), and indicates a polystyrene-equivalent weight average molecular weight calculated using a polystyrene standard sample. The weight average molecular weight (Mw) can be measured, for example, under the following conditions and procedures. [Measurement conditions] Equipment: GPC-8020 (Tosoh Corporation) Column: TSK G2000HXL and G4000HXL (Tosoh Corporation) ·Temperature: 40℃ Solvent: Chloroform ·Flow rate: 1.0mL / min [Measurement procedure] 1 mL of a sample with a concentration of 0.5% by mass is injected, and the molecular weight distribution of the polymer measured under the above measurement conditions is used to calculate the number average molecular weight (Mn) and weight average molecular weight (Mw) using a molecular weight calibration curve created with a monodisperse polystyrene standard sample. The molecular weight distribution is the value obtained by dividing Mw by Mn. The porous body is dissolved in chloroform at a concentration of 0.2% by mass, and then filtered through a 0.2 μm filter, and the filtrate is used as the sample.

[0025] The content of the compound is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 15% by mass or more and 85% by mass or less, and more preferably 25% by mass or more and 75% by mass or less, relative to the photoelectric conversion layer. When the content is 15% by mass or more, light can be sufficiently absorbed, so that the power generation (photoelectric conversion efficiency) is high. When the content is 85% by mass or less, the solubility in the solvent is good, and film formation is easy.

[0026] The method for synthesizing the compound is not particularly limited and may be appropriately selected depending on the purpose. For example, the compound may be produced by synthesizing a monomer having a functional group suitable for a polymerization reaction, dissolving the monomer in an organic solvent as necessary, and polymerizing the monomer using a known aryl coupling reaction using a base, a catalyst, a ligand, or the like.

[0027] The polymerization by the aryl coupling reaction is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include polymerization by Suzuki coupling reaction, polymerization by Stille coupling reaction, CH activation direct polymerization, etc. Among these, the method of polymerization by Suzuki coupling reaction and the method of polymerization by Stille coupling reaction are preferred from the viewpoint of reactivity.

[0028] The Suzuki coupling reaction is not particularly limited and can be appropriately selected depending on the purpose. For example, a known method (see Chem. Rev. 1995, 95, 7, 2457-2483) can be used. The Suzuki coupling reaction can be carried out in any solvent using a palladium catalyst in the presence of a base.

[0029] The palladium catalyst is not particularly limited and can be appropriately selected according to purpose, and can be, for example, Pd(0) catalyst, Pd(II) catalyst.Specifically, can be palladium [tetrakis(triphenylphosphine)], palladium acetates, dichlorobis(triphenylphosphine)palladium, palladium acetate, tris(dibenzylideneacetone)dipalladium and bis(dibenzylideneacetone)palladium, but from the viewpoint of ease of reaction (polymerization) operation and reaction (polymerization) rate, dichlorobis(triphenylphosphine)palladium, palladium acetate and tris(dibenzylideneacetone)dipalladium are preferred. The amount of the palladium catalyst to be added is not particularly limited as long as it is an effective amount as a catalyst and can be appropriately selected depending on the purpose. Generally, however, the amount is preferably 0.0001 mol or more and 0.5 mol or less, and more preferably 0.0003 mol or more and 0.1 mol or less, per 1 mol of monomer.

[0030] The base is not particularly limited and can be appropriately selected depending on the purpose. Examples of the base include inorganic bases, organic bases, and inorganic salts. Examples of the inorganic base include potassium carbonate, sodium carbonate, barium hydroxide, and potassium phosphate. Examples of the organic base include triethylamine and tributylamine. The inorganic salt may, for example, be cesium fluoride.

[0031] The Suzuki coupling reaction is usually carried out in a solvent. The solvent is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include N,N-dimethylformamide, toluene, dimethoxyethane, tetrahydrofuran, methylene chloride, etc. Among these, toluene and tetrahydrofuran are preferred from the viewpoint of the solubility of the polymer material. In addition, as the solvent, an aqueous solution containing a base may be added to the reaction solution as the addition of a base, and the reaction may be carried out in a two-phase system of an aqueous phase and an organic phase. When an inorganic salt is used as the base, the reaction is usually carried out by adding an aqueous solution containing a base to the reaction solution from the viewpoint of the solubility of the inorganic salt. In addition, when the reaction is carried out in a two-phase system, a phase transfer catalyst such as a quaternary ammonium salt may be added as necessary.

[0032] The temperature at which the Suzuki coupling reaction is carried out is not particularly limited and can be appropriately selected depending on the purpose, and although it depends on the solvent, it is preferably from 40° C. to 160° C., and from the viewpoint of increasing the molecular weight of the polymer material, more preferably from 60° C. to 120° C. Alternatively, the temperature may be raised to near the boiling point of the solvent and refluxed.

[0033] The reaction time for carrying out the Suzuki coupling reaction is not particularly limited and can be appropriately selected depending on the purpose. The reaction time may be determined to be the time when a desired degree of polymerization is reached, but is preferably from 0.1 hours to 200 hours, and more preferably from 0.5 hours to 30 hours in terms of reaction efficiency.

[0034] The Suzuki coupling reaction is preferably carried out in an inert atmosphere such as argon gas or nitrogen gas in a reaction system in which the palladium catalyst is not deactivated, for example, in a system that is sufficiently degassed with argon gas or nitrogen gas.

[0035] The method using the Stille coupling reaction is not particularly limited and can be appropriately selected depending on the purpose. Examples of the method include known methods such as the method described in Angew. Chem. Int. Ed. 2004, 43, 4704-4734.

[0036] The lower limit of the reaction temperature of the aryl coupling reaction is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of reactivity, it is preferably −100° C., more preferably −20° C., and particularly preferably 0° C. The upper limit of the reaction temperature is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of stability of the monomer and polymer material, it is preferably 200° C., more preferably 150° C., and particularly preferably 120° C.

[0037] In the polymerization by the aryl coupling reaction, the method for extracting the polymer material of the present invention from the reaction solution after completion of the reaction is not particularly limited and can be appropriately selected depending on the purpose. For example, known methods can be used. Examples of the known method include a method of adding a reaction solution to a lower alcohol such as methanol, filtering the precipitate, and drying the residue, etc. If the purity of the obtained polymer material is low, it can be purified by recrystallization, continuous extraction using a Soxhlet extractor or the like, column chromatography, etc. When the polymer material of the present invention is used for producing an organic photoelectric conversion element, if a polymerization active group remains at the end of the polymer compound, the properties such as durability of the organic photoelectric conversion element may be deteriorated. Therefore, it is preferable to protect the end with a stable group.

[0038] The stable group protecting the terminal end is not particularly limited and can be appropriately selected depending on the purpose. Examples of the stable group include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a fluoroalkyl group, a fluoroalkoxy group, an aryl group, an arylamino group, and a monovalent heterocyclic group. Examples of the arylamino group include a phenylamino group, a diphenylamino group, etc. From the viewpoint of improving hole transport properties, it is preferable that the stable group protecting the terminal is a group that imparts electron donating properties, such as an arylamino group. Examples of the monovalent heterocyclic group include a thienyl group, a pyrrolyl group, a furyl group, a pyridyl group, a quinolyl group, and an isoquinolyl group. In addition, the polymerization active group remaining at the end of the polymer compound may be replaced with a hydrogen atom instead of a stable group. When the polymer compound is a polymer material, a group having a conjugated bond in which the conjugated structure of the main chain of the polymer compound and the conjugated structure of the stable group protecting the end are continuous can also be preferably used as a stable group protecting the end. Examples of the group having a conjugated bond include an aryl group and a monovalent heterocyclic group having aromaticity.

[0039] The method for identifying the compound having the structure represented by the general formula (1) synthesized by the synthesis method is not particularly limited and can be appropriately selected depending on the purpose. For example, the compound can be identified by NMR analysis, GPC analysis, MS analysis, etc. The device used for the NMR analysis is not particularly limited and can be appropriately selected depending on the purpose. For example, ECX-500 (manufactured by JEOL Ltd.) can be mentioned. The apparatus used for the GPC analysis is not particularly limited and can be appropriately selected depending on the purpose. For example, GPC-8020 (manufactured by Tosoh Corporation) can be mentioned. The apparatus used for the MS analysis is not particularly limited and can be appropriately selected depending on the purpose. For example, Autoflex3 (manufactured by Bruker Daltonics) can be mentioned.

[0040] The polymeric material has a deep HOMO level, is excellent in air stability, and is expected to improve the open circuit voltage due to the material. In addition, by introducing a soluble group such as an alkyl group into such a rigid molecular skeleton, it is possible to more advantageously form an organic semiconductor film having a regular assembly state such as crystallinity, liquid crystallinity, and orientation while ensuring solubility in general organic solvents. In particular, in the general formula (1), it is desirable that the alkyl group substituted for the nitrogen atom is branched. The branched alkyl chain significantly increases the solubility. This allows the organic thin film to be made thick. A thicker film can absorb more light, leading to an improvement in power generation.

[0041] -N-type semiconductor materials- The N-type semiconductor material is not particularly limited as long as it functions as an N-type semiconductor material with respect to the polymer material represented by general formula (1), and can be appropriately selected according to the purpose, and examples thereof include fullerene-based N-type semiconductor materials such as fullerene and fullerene derivatives, and non-fullerene-based N-type semiconductor materials. These may be used alone or in combination of two or more. Among these, non-fullerene-based N-type semiconductor materials are preferred because they can obtain a better photoelectric conversion efficiency.

[0042] As the fullerene-based N-type semiconductor material, an appropriately synthesized material or a commercially available product may be used. The commercially available product is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include PC71BM (phenyl C71 butyric acid methyl ester, manufactured by Frontier Carbon Corporation), PC61BM (manufactured by Frontier Carbon Corporation), and fullerene indene diadduct (manufactured by Frontier Carbon Corporation).

[0043] The non-fullerene-based N-type semiconductor is not particularly limited and can be appropriately selected depending on the purpose. For example, known non-fullerene-based semiconductors can be used. Examples of the already known non-fullerene-based N-type semiconductors include those described in [J. Mater. Chem. A, 2022,10, 3255-3295, Adv. Sci. 2022,9, 220187].

[0044] As the non-fullerene-based N-type semiconductor, an appropriately synthesized product or a commercially available product may be used. The commercially available product is not particularly limited and can be appropriately selected depending on the purpose. For example, IT-4F (substance name: 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6,7-difluoro)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-D:2′,3′-D′]-S-indaceno[1,2-b:5,6-b′]dithiophene, manufactured by Ossila, has the following structural formula (1 )), ITIC (substance name: 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene, manufactured by Ossila, a compound represented by the following structural formula (2)), Y6 (substance name: 2,2'-((2Z,2'Z)-((12,13-bis Bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanillylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene) ) dimalononitrile, manufactured by Ossila, a compound represented by the following structural formula (3), IO-4Cl (substance name: 3,9-bis[5,6-dichloro-1H-indene-1,3(2H)dione]-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene, manufactured by Ossila, a compound represented by the following structural formula (4), and the like are preferred. [ka] [ka] [ka] [ka]

[0045] The content of the N-type semiconductor material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 25% by mass or more and 75% by mass or less with respect to the photoelectric conversion layer.

[0046] -Other ingredients- The other components are not particularly limited and can be appropriately selected depending on the purpose. Examples of the other components include inorganic compounds such as zinc oxide and titanium oxide, and various additives such as 1,8-diiodooctane, 1,8-octanedithiol, and 1-chloronaphthalene.

[0047] The average thickness of the photoelectric conversion layer is not particularly limited and can be appropriately selected according to the purpose, but is preferably 50 nm to 1,500 nm, more preferably 100 nm to 1,000 nm. When the average thickness is 50 nm or more, the light absorption by the photoelectric conversion layer increases and carrier generation becomes sufficient. When the average thickness is 1,500 nm or less, the transport efficiency of carriers generated by light absorption can be maintained.

[0048] The method for measuring the average thickness of the photoelectric conversion layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the average thickness may be measured using a stylus profiling system manufactured by Bruker.

[0049] -Method of forming photoelectric conversion layer- The method for forming the photoelectric conversion layer is not particularly limited and can be appropriately selected depending on the purpose. For example, the photoelectric conversion layer can be formed by applying a photoelectric conversion layer forming solution onto an object to be coated and then drying the applied solution.

[0050] The photoelectric conversion layer forming solution contains a compound (polymer material) having a structure represented by the general formula (1) and the N-type semiconductor material, and preferably contains an organic solvent, and further contains other components as necessary.

[0051] As the polymer material, the same materials as those contained in the photoelectric conversion layer can be used.

[0052] As the N-type semiconductor material, the same material as that contained in the photoelectric conversion layer can be used.

[0053] The total content of the polymer material and the N-type semiconductor material is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 mg / mL to 100 mg / mL in the photoelectric conversion layer forming solution, which makes it possible to easily prepare a photoelectric conversion layer having a uniform thickness.

[0054] The organic solvent is not particularly limited and can be appropriately selected according to the purpose, and examples thereof include methanol, ethanol, butanol, toluene, xylene, o-chlorophenol, acetone, ethyl acetate, ethylene glycol, tetrahydrofuran, dichloromethane, chloroform, dichloroethane, chlorobenzene (monochlorobenzene), dichlorobenzene, trichlorobenzene, o-dichlorobenzene, chloronaphthalene, dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, and γ-butyrolactone. These may be used alone or in combination of two or more. Among these, chloroform, chlorobenzene, and o-dichlorobenzene are preferred.

[0055] As the other components, the same components as those contained in the photoelectric conversion layer can be used.

[0056] The coating method is not particularly limited and may be appropriately selected depending on the purpose such as control of the average thickness, control of the orientation, properties of the polymer material, etc. Examples of the coating method include spin coating, blade coating, slit die coating, screen printing coating, bar coater coating, mold coating, printing transfer method, immersion and pulling method, inkjet method, spray method, vacuum deposition method, etc. Among these, spin coating is preferred.

[0057] When the spin coating is performed, the polymer material having the structure represented by the general formula (1) and the n-type semiconductor material are preferably at a concentration of 10 mg / mL to 100 mg / mL (the mass of the organic material having the structure represented by the general formula (1) and the n-type semiconductor material relative to the volume of the solution containing the organic material having the structure represented by the general formula (1), the n-type semiconductor material, and a solvent), and by using the above concentrations, a homogeneous photoelectric conversion layer can be easily produced.

[0058] The drying method is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include annealing treatment under reduced pressure or in an inert atmosphere (nitrogen, argon, etc.) By carrying out the annealing treatment, the effective area where the laminated layers penetrate each other at the interface and contact each other is increased, so that the short-circuit current can be increased. The annealing treatment may be carried out after the electrodes are formed.

[0059] The drying temperature is not particularly limited and can be appropriately selected depending on the purpose, but is preferably from 40° C. to 300° C., and more preferably from 50° C. to 150° C.

[0060] The drying time is not particularly limited and can be appropriately selected depending on the purpose, but is preferably from 1 minute to 30 minutes, and more preferably from 5 minutes to 10 minutes.

[0061] The photoelectric conversion layer may be formed by sequentially depositing the polymer material and the N-type semiconductor material to form a planar junction interface. However, in order to increase the area of ​​the junction interface, it is preferable to form a bulk heterojunction in which these materials are mixed three-dimensionally. The bulk heterojunction can be formed, for example, by dissolving highly soluble materials in an organic solvent to prepare a solution in which the P-type polymer material and the N-type polymer material are mixed in molecular form, applying the solution, and then drying the solution to remove the solvent. In addition, the aggregation state of each semiconductor can be optimized by further performing a heat treatment. When a material having poor solubility is used, a mixed layer can be formed by dispersing the polymer material in a solvent and applying the solution.

[0062] <Substrate> The substrate is not particularly limited and can be appropriately selected depending on the purpose. Examples of the substrate include plastic substrates such as transparent plastic plates and transparent plastic films, glass, and inorganic transparent crystals. When the substrate is a plastic substrate, it is preferable to use a film having high gas barrier properties in order to prevent the intrusion of oxygen and moisture.

[0063] <First electrode> The first electrode is not particularly limited and may be appropriately selected depending on the purpose. For example, an electrode that is transparent to visible light and an electrode that is opaque to visible light may be used.

[0064] The electrode that is transparent to visible light is not particularly limited and can be appropriately selected depending on the purpose. Examples of the electrode that is transparent to visible light include conductive metal oxides such as tin-doped indium oxide (hereinafter sometimes referred to as "ITO"), fluorine-doped tin oxide (hereinafter sometimes referred to as "FTO"), antimony-doped tin oxide (hereinafter sometimes referred to as "ATO"), aluminum-doped zinc oxide (hereinafter sometimes referred to as "AZO"), and gallium-doped zinc oxide (hereinafter sometimes referred to as "GZO").

[0065] The structure of the first electrode is not particularly limited and can be appropriately selected depending on the purpose. Examples of the structure include a metal electrode having a mesh-like or striped structure that allows light to pass through, provided on a substrate such as a glass substrate, and a laminate of carbon nanotubes, graphene, or the like to a degree that the electrode is transparent.

[0066] As the first electrode, it is preferable to use a metal lead wire or the like, since the substrate resistance can be reduced. The material of the metal lead wire is not particularly limited and can be appropriately selected depending on the purpose. Examples of the material include metals such as aluminum, copper, silver, gold, platinum, and nickel. The metal lead wires may be formed, for example, by providing them on a substrate by vapor deposition, sputtering, pressure bonding, or the like, and then providing ITO or FTO thereon.

[0067] The average thickness of the first electrode is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.005 μm or more and 10 μm or less, and more preferably 0.05 μm or more and 1 μm or less.

[0068] The method for measuring the average thickness of the first electrode is not particularly limited and can be appropriately selected depending on the purpose. For example, the average thickness of the first electrode can be measured by the same method as that for the average thickness of the photoelectric conversion layer.

[0069] <Electron transport layer> The electron transport layer is not particularly limited and may be appropriately selected depending on the purpose, but preferably contains an inorganic material and an electron-accepting conjugated polymer material.

[0070] The inorganic material is not particularly limited and can be appropriately selected depending on the purpose. Examples of the inorganic material include zinc oxide, titanium oxide, tin oxide, lithium fluoride, and calcium.

[0071] The electron-accepting conjugated polymer material is not particularly limited and can be appropriately selected depending on the purpose. Examples of the electron-accepting conjugated polymer material include perylene tetracarboxylic anhydride, perylene tetracarboxylic diimide, oxazole derivatives, triazole derivatives, phenanthroline derivatives, phosphine oxide derivatives, fullerene compounds, CNTs, and CN-PPV. The average thickness of the electron transport layer is not particularly limited and may be appropriately selected depending on the purpose, but it is preferable for the electron transport layer to cover the entire surface as thinly as possible, and more preferably from 10 nm to 100 nm.

[0072] The average thickness of the electron transport layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 10 nm or more and 100 nm or less.

[0073] The method for measuring the average thickness of the electron transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the average thickness of the electron transport layer may be measured by the same method as that for the average thickness of the photoelectric conversion layer.

[0074] The electron transport layer is not particularly limited and may be appropriately selected depending on the purpose, but a film of a basic carboxylic acid may be formed on the surface. The basic carboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples of the basic carboxylic acid include 4-(N,N-dimethylamino)-benzoic acid, 4-(N,N-diethylamino)-benzoic acid, and 4-(N,N-dibenzylamino)-benzoic acid.

[0075] -Method of forming electron transport layer- The method for forming the electron transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the electron transport layer may be formed by applying a solution for forming the electron transport layer onto an object to be coated and then drying the applied solution.

[0076] The solution for forming the electron transport layer preferably contains an inorganic material, an electron-accepting conjugated polymer material, and an organic solvent.

[0077] As the inorganic material, the same materials as those contained in the electron transport layer can be used.

[0078] As the electron-accepting conjugated polymer material, the same material as that contained in the electron transport layer can be used.

[0079] The organic solvent is not particularly limited and can be appropriately selected according to the purpose, and examples thereof include methanol, ethanol, methoxyethanol, butanol, toluene, xylene, o-chlorophenol, acetone, ethyl acetate, ethylene glycol, tetrahydrofuran, dichloromethane, chloroform, dichloroethane, chlorobenzene (monochlorobenzene), dichlorobenzene, trichlorobenzene, o-dichlorobenzene, chloronaphthalene, dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, γ-butyrolactone, and ethanolamine. These may be used alone or in combination of two or more. Among these, chloroform, chlorobenzene, and o-dichlorobenzene are preferred.

[0080] <Hole transport layer> The hole transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, it is preferable that the hole transport layer contains a conductive polymer, an aromatic amine derivative, or an inorganic compound. By providing the hole transport layer, the efficiency of collecting holes can be improved.

[0081] The conductive polymer is not particularly limited and can be appropriately selected depending on the purpose. For example, PEDOT:PSS (polyethylenedioxythiophene:polystyrenesulfonic acid) is included.

[0082] The inorganic compound is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include molybdenum oxide, vanadium oxide, nickel oxide, etc. These may be used alone or in combination of two or more. Among these, molybdenum oxide is preferred.

[0083] The average thickness of the hole transport layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 1 nm or more and 50 nm or less.

[0084] The method for measuring the average thickness of the hole transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the average thickness of the hole transport layer may be measured by the same method as that for the average thickness of the photoelectric conversion layer.

[0085] -Method of forming hole transport layer- The method for forming the hole transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the hole transport layer may be formed by vacuum deposition of a conductive polymer, an aromatic amine derivative, an inorganic compound, or the like on an object to be coated.

[0086] <Second electrode> The second electrode is not particularly limited and may be appropriately selected depending on the purpose. For example, an electrode that is transparent to visible light and an electrode that is opaque to visible light may be used.

[0087] The electrode that is transparent to visible light is not particularly limited and can be appropriately selected depending on the purpose. Examples of the electrode include conductive metal oxides such as silver, tin-doped indium oxide (hereinafter sometimes referred to as "ITO"), fluorine-doped tin oxide (hereinafter sometimes referred to as "FTO"), antimony-doped tin oxide (hereinafter sometimes referred to as "ATO"), aluminum-doped zinc oxide (hereinafter sometimes referred to as "AZO"), and gallium-doped zinc oxide (hereinafter sometimes referred to as "GZO").

[0088] The structure of the second electrode is not particularly limited and can be appropriately selected depending on the purpose. Examples of the structure include a metal electrode having a mesh-like or striped structure that allows light to pass through, provided on a substrate such as a glass substrate, and a laminate of carbon nanotubes, graphene, or the like to a degree that the electrode is transparent.

[0089] As the second electrode, it is preferable to use a metal lead wire or the like, since the substrate resistance can be reduced. The material of the metal lead wire is not particularly limited and can be appropriately selected depending on the purpose. Examples of the material include metals such as aluminum, copper, silver, gold, platinum, and nickel. The metal lead wires may be formed, for example, by providing them on a substrate by vapor deposition, sputtering, pressure bonding, or the like, and then providing ITO or FTO thereon.

[0090] The average thickness of the second electrode is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.005 μm or more and 10 μm or less, and more preferably 0.05 μm or more and 1 μm or less.

[0091] The method for measuring the average thickness of the second electrode is not particularly limited and can be appropriately selected depending on the purpose. For example, the average thickness of the second electrode can be measured by the same method as that for the average thickness of the photoelectric conversion layer.

[0092] <Other materials> The other members are not particularly limited and may be appropriately selected depending on the purpose. Examples of the other members include a gas barrier layer, a protective layer, and a buffer layer. Examples of materials for the gas barrier layer include inorganic materials such as silicon nitride and silicon oxide.

[0093] (electronic equipment) An electronic device of the present invention includes the photoelectric conversion element of the present invention and a device electrically connected to the photoelectric conversion element.

[0094] (Power supply module) The power supply module of the present invention includes the photoelectric conversion element of the present invention and a power supply IC electrically connected to the photoelectric conversion element.

[0095] <Application> In recent years, photoelectric conversion elements that efficiently generate electricity even with weak light are required, especially as energy harvesting elements. LED lights and fluorescent lights are representative of weak light. They are mainly used indoors and are particularly called indoor light. The illuminance of such light is about 20 Lux to 1,000 Lux, which is very weak light compared to direct sunlight (about 100,000 Lux). The photoelectric conversion element of the present invention exhibits high conversion efficiency even in the case of weak light such as the indoor light, and also exhibits high photoelectric conversion efficiency in a medium illuminance environment such as 10,000 Lux, and can be applied to a power supply device by combining it with a circuit board or the like that controls the generated current. Examples of devices that use such a power supply device include electronic desk calculators and wristwatches. In addition, a power supply device having the photoelectric conversion element of the present invention can be applied to mobile phones, electronic notebooks, electronic paper, etc. In addition, a power supply device having the photoelectric conversion element of the present invention can be used as an auxiliary power source to extend the continuous use time of rechargeable or battery-powered electrical appliances. Furthermore, it can also be applied as an image sensor. EXAMPLES

[0096] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples.

[0097] [Synthesis example 1 of polymeric material: synthesis of example compound 1] 2,6-Dibromo-4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene (0.74g, 1.0mmol, manufactured by Sunatech) and (4,8-bis(5-(2-hexyldecyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene-2,6-diyl)bis(trimethylstannane) (1.13g, 1.0mmol, manufactured by Sunatech) were added to chlorobenzene (100mL). After bubbling with nitrogen (N2) for 15 minutes, tris(dibenzylideneacetone)dipalladium (hereinafter sometimes referred to as "Pd2(dba)3") (0.021 g, 0.020 mmol) and tri(o-tolyl)phosphine (0.024 g, 0.080 mmol) were added and stirred at 100°C for 24 hours to obtain a reaction mixture. After cooling to room temperature, the reaction mixture was poured into methanol to obtain a precipitate. The resulting precipitate was filtered as a crude product, and purified by repeated Soxhlet extraction with methanol, acetone, hexane, and chloroform, and finally the chloroform-soluble fraction was concentrated under reduced pressure and reprecipitated in methanol. After drying under vacuum, the exemplary compound 1 shown in Table 1 was obtained as a dark red solid (yield=1.28 g, 93%). The results of PGC analysis of the obtained exemplary compound 1 are shown below. GPC (THF): Mn = 526 kDa, Mw = 2130 kDa, PDI = 4.0. Anal. Calcd (%) for (C 84 H 112 S8)n: C 73.20, H 8.19; found: C 73.11, H 8.24.

[0098] [Polymer material synthesis example 2: synthesis of example compound 4] Except for changing "2,6-dibromo-4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" to "2,6-dibromo-4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" in Synthesis Example 1, synthesis was performed in the same manner as in Synthesis Example 1 to obtain Example Compound 4 shown in Table 1. The PGC analysis results for the obtained Example Compound 4 are shown below. GPC (THF): Mn =150 kDa, Mw =675 kDa, PDI=4.5

[0099] [Polymer Material Synthesis Example 3: Synthesis of Example Compound 9] Except for changing "2,6-dibromo-4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" to "2,6-dibromo-4,8-bis(5-(2-butyloctyl)-thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" in Synthesis Example 1, synthesis was performed in the same manner as in Synthesis Example 1 to obtain Example Compound 9 shown in Table 1. The PGC analysis results for the obtained Example Compound 9 are shown below. GPC (THF): Mn =620 kDa, Mw =2312 kDa, PDI=3.7

[0100] [Polymer Material Synthesis Example 4: Synthesis of Example Compound 20] Except for changing "2,6-dibromo-4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" to "2,6-dibromo-4,8-bis(5-(2-octyldodecyl)-thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene" in Synthesis Example 1, synthesis was performed in the same manner as in Synthesis Example 1 to obtain Example Compound 20 shown in Table 1. The PGC analysis results for the obtained Example Compound 20 are shown below. GPC (THF): Mn =702 kDa, Mw =2835 kDa, PDI=3.9

[0101] Example 1 <Preparation of solution for forming electron transport layer> 1 g of zinc acetate (manufactured by Aldrich Co.), 0.28 g of ethanolamine (manufactured by Aldrich Co.), and 10 ml of methoxyethanol (manufactured by Wako Co., Ltd.) were stirred overnight at room temperature to prepare a solution for forming an electron transport layer.

[0102] <Preparation of solution for forming photoelectric conversion layer> 20 mg of the exemplary compound 9 as a polymer material, 20 mg of PC61BM (manufactured by Frontier Carbon Corp.) as an N-type semiconductor material, and 1 ml of monochlorobenzene were mixed with stirring to prepare a solution for forming a photoelectric conversion layer.

[0103] <Fabrication of photoelectric conversion element> The solution for forming the electron transport layer was applied by spin coating onto an ITO substrate (manufactured by Geomatec Co., Ltd.) serving as a substrate and a first electrode, and then dried at 200°C for 10 minutes to form an electron transport layer with an average thickness of 20 nm. Next, the photoelectric conversion layer forming solution was applied onto the electron transport layer by spin coating, and then a photoelectric conversion layer having an average thickness of 200 nm was formed. Next, molybdenum oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) was deposited on the electron transport layer by vacuum deposition to form a hole transport layer with an average thickness of 10 nm. Next, silver was vacuum deposited on the hole transport layer to form a second electrode having an average thickness of 100 nm, thereby obtaining a photoelectric conversion element 1 (hereinafter sometimes referred to as "solar cell element 1") having the structure shown in Figure 1. The average thicknesses of the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the second electrode were measured by the following method. The measurement results are shown in Table 2 below.

[0104] <Method of measuring average thickness> The average thicknesses of the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the second electrode in the photoelectric conversion element 1 were measured using a stylus profiling system manufactured by Bruker.

[0105] Example 2 In the preparation of the photoelectric conversion layer forming solution of Example 1, except that 20 mg of the exemplary compound 9 was changed to 20 mg of the exemplary compound 20 as the polymer material, a photoelectric conversion element 2 was obtained in the same manner as in Example 1. The average thicknesses of the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below.

[0106] Example 3 In the preparation of the photoelectric conversion layer forming solution of Example 1, except that 20 mg of the exemplary compound 9 was used as the polymer material in place of 20 mg of the exemplary compound 1, a photoelectric conversion element 3 was obtained in the same manner as in Example 1. The average thicknesses of the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below.

[0107] Example 4 In the preparation of the photoelectric conversion layer forming solution of Example 1, except that 20 mg of the exemplary compound 9 was used as the polymer material in place of 20 mg of the exemplary compound 4, a photoelectric conversion element 4 was obtained in the same manner as in Example 1. The average thicknesses of the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below.

[0108] Example 5 In the preparation of the photoelectric conversion layer forming solution of Example 3, 20 mg of PC61BM as an N-type semiconductor material was changed to 20 mg of IT-4F (substance name: 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6,7-difluoro)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-D:2',3'-D']-S-indaceno[1,2-b:5,6-b']dithiophene, manufactured by Ossila, a compound represented by the following structural formula (1)), except that, a photoelectric conversion element 5 was obtained in the same manner as in Example 3. The average thicknesses of the electron transport layer, photoelectric conversion layer, hole transport layer, and second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below. [ka]

[0109] Example 6 In preparing the photoelectric conversion layer forming solution of Example 3, except that 20 mg of PC61BM as the N-type semiconductor material was changed to 20 mg of IO-4Cl (a compound represented by the following structural formula (4), manufactured by Ossila), a photoelectric conversion element 6 was obtained in the same manner as in Example 3. The average thicknesses of the electron transport layer, photoelectric conversion layer, hole transport layer, and second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below. [ka]

[0110] Comparative Example 1 In preparing the photoelectric conversion layer forming solution of Example 1, 20 mg of the exemplary compound 9 as the polymer material was changed to 10 mg of the comparative compound 1 represented by the following structural formula (5), and 20 mg of PC61BM as the N-type semiconductor material was changed to 10 mg of PC71BM, but the same procedure was followed as in Example 1 to obtain a photoelectric conversion element 7. The average thicknesses of the electron transport layer, photoelectric conversion layer, hole transport layer, and second electrode were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below. [ka]

[0111] [Table 2]

[0112] For each of the photoelectric conversion elements obtained in Examples 1 to 6 and Comparative Example 1, the "photoelectric conversion efficiency" was evaluated based on the following evaluation method.

[0113] <Photoelectric conversion efficiency> For each of the photoelectric conversion elements obtained in Examples 1 to 6 and Comparative Example 1, a white LED light source (LDA11N-G, manufactured by Toshiba Corporation) was used to measure the luminance of 68 μW / cm 2 The photoelectric conversion efficiency of each element was measured using an IV measurement system manufactured by System House Sunrise. The output of the white LED light source was measured using a spectrophotometer C-7000 manufactured by Sekonic Corp. The evaluation results are shown in Tables 3 and 4 below.

[0114] [Table 3]

[0115] [Table 4]

[0116] As shown in Tables 3 and 4, the photoelectric conversion elements of Examples 1 to 6 had a low illuminance (68 μW / cm ) compared to the photoelectric conversion element of Comparative Example 1. 2 ) has excellent photoelectric conversion efficiency.

[0117] For example, aspects of the present invention are as follows. <1> A photoelectric conversion element having a photoelectric conversion layer, The photoelectric conversion element is characterized in that the photoelectric conversion layer contains a polymer material having a structure represented by the following general formula (1) and an N-type semiconductor material. [ka] (In the above general formula (1), R 1 , R 2 , R 3 , and R 4 represents an alkyl group, a thioalkyl group, or an alkoxy group having 2 to 20 carbon atoms; R 1 and R 3 and are different from each other or R 2 and R 4 are different from each other, n is an integer of 50 or more and 1,000 or less, and X and Y are halogen or hydrogen. <2> R in the above general formula (1) 1 and R 2 is an alkyl group having 2 to 8 carbon atoms. <1> The photoelectric conversion element according to the present invention is <3> In the general formula (1), R3 and R 4 is an alkyl group having 16 to 20 carbon atoms. <1> from <2> The photoelectric conversion element according to any one of the above items. <4> In the general formula (1), R 1 and R 3 And R 2 and R 4 The difference in the number of carbon atoms in at least one of the above is 8 or more and 14 or less. <1> from <3> The photoelectric conversion element according to any one of the above items. <5> In the general formula (1), X and Y are hydrogen. <1> from <4> The photoelectric conversion element according to any one of the above items. <6> In the general formula (1), X is halogen and Y is hydrogen. <1> from <5> The photoelectric conversion element according to any one of the above items. <7> The N-type semiconductor material is a fullerene-based N-type semiconductor material. <1> from <6> The photoelectric conversion element according to any one of the above items. <8> The N-type semiconductor material is a non-fullerene-based N-type semiconductor material. <1> from <6> The photoelectric conversion element according to any one of the above items. <9> The above <1> from <8> and a device electrically connected to the photoelectric conversion element. <10> The above <1> from <8> and a power supply IC electrically connected to the photoelectric conversion element.

[0118] The above <1> from <8> The photoelectric conversion element according to <9> The electronic device according to the <10> The power supply module described in the above is capable of solving the above-mentioned problems in the prior art and achieving the object of the present invention. [Explanation of symbols]

[0119] 1 Board 2 First electrode 3 Electron transport layer 4 Photoelectric conversion layer 5. Hole transport layer 6 Second electrode [Prior art documents] [Patent documents]

[0120] [Patent Document 1] Korea Registration No. 10-1687018

Claims

1. A photoelectric conversion element having a photoelectric conversion layer, The photoelectric conversion element, wherein the photoelectric conversion layer contains a polymer material having a structure represented by the following general formula (1) and an N-type semiconductor material: 【Chemistry 1】 (In the above general formula (1), R １ , R ２ , R ３ , and R ４ represents an alkyl group, a thioalkyl group, or an alkoxy group having 2 to 20 carbon atoms; R １ and R ３ and are different from each other or R ２ and R ４ are different from each other, n is an integer of 50 to 1,000, and X and Y are halogen or hydrogen.

2. R in the above general formula (1) １ and R ２ The photoelectric conversion element according to claim 1 , wherein is an alkyl group having 2 to 8 carbon atoms.

3. In the general formula (1), R ３ and R ４ The photoelectric conversion element according to claim 1 , wherein is an alkyl group having 16 to 20 carbon atoms.

4. In the general formula (1), R １ and R ３ And R ２ and R ４ 3. The photoelectric conversion element according to claim 1, wherein the difference in the number of carbon atoms in at least one of the above is 8 or more and 14 or less.

5. 3. The photoelectric conversion element according to claim 1, wherein in the general formula (1), X and Y are hydrogen.

6. 3. The photoelectric conversion element according to claim 1, wherein in the general formula (1), X is a halogen and Y is hydrogen.

7. 3. The photoelectric conversion element according to claim 1, wherein the N-type semiconductor material is a fullerene-based N-type semiconductor material.

8. 3. The photoelectric conversion element according to claim 1, wherein the N-type semiconductor material is a non-fullerene-based N-type semiconductor material.

9. 3. An electronic device comprising: the photoelectric conversion element according to claim 1; and a device electrically connected to the photoelectric conversion element.

10. 3. A power supply module comprising: the photoelectric conversion element according to claim 1; and a power supply IC electrically connected to the photoelectric conversion element.

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