Solar cell and manufacturing method therefor

Abstract

To provide a solar cell containing a metal halide perovskite compound in a photoelectric conversion layer, containing a non-fullerene material to an electron transport layer, and having a good conversion efficiency.SOLUTION: A solar cell contains: a photoelectric conversion layer containing a metal halide perovskite compound; a first electron transport layer arranged onto the photoelectric conversion layer; and a second electron transport layer arranged onto the first electron transport layer. The first electron transport layer contains a 3,4,9,10-perylenetetracarboxylic diimide derivative, and the second electron transport layer contains one or more kinds of positive hole block chemical compounds selected from a group consisting of a 1,10-phenanthroline derivative expressed by a specific formula, a phenyl pyridine derivative expressed by a specific formula, an organic metal complex having lithium or aluminum and 8-quinolinol ligand, and a conductive metal oxide material containing tin.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a solar cell and a method for manufacturing the same. [Background technology]

[0002] Solar cells that use metal halide perovskite organic compounds in the photoelectric conversion layer are generally called perovskite solar cells. Many of the layers that make up the perovskite solar cell can be formed by coating a solution containing an organic or inorganic substance. Therefore, perovskite solar cells can be manufactured at low cost. Furthermore, 2 In perovskite solar cells with a small area of ​​less than 100 nm, an energy conversion efficiency of over 25% has been reported, and perovskite solar cells are expected to have high performance. In addition, it is also possible to easily adjust the band gap of perovskite solar cells by changing the composition of the photoelectric conversion layer. Therefore, tandem solar cells in which crystalline silicon solar cells and perovskite solar cells are stacked, and tandem solar cells in which multiple perovskite solar cells with different band gaps are stacked, are also attracting attention.

[0003] As an example of the structure of a solar cell of a perovskite type solar cell, a structure (also called an inverted structure) in which a glass substrate / anode layer / hole transport layer / photoelectric conversion layer containing a metal halide perovskite compound / electron transport layer / cathode layer are laminated in this order from the sunlight incident side is known. The electron transport layer of such a perovskite type solar cell with an inverted structure contains C 60 Fullerene or phenyl C 61 C such as butyric acid methyl ester (also referred to herein as "PCBM"). 60 Fullerene derivatives are widely used. However, C 60 C such as fullerene and PCBM 60 Fullerene derivatives are prone to degradation by air, and as a result of this degradation, the characteristics of perovskite solar cells tend to deteriorate. 60Another issue is that fullerene derivatives are expensive, which can easily increase the cost of perovskite solar cells.

[0004] In recent years, therefore, the use of non-fullerene-based materials in the electron transport layer of perovskite solar cells has been considered. Perylene diimide derivatives, for example, are known as non-fullerene-based materials that can be used in the electron transport layer (for example, Non-Patent Documents 1 and 2). Non-Patent Document 3 also proposes laminating the perylene diimide derivative with a buffer layer made of zinc oxide. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Daizhe Wang et al., "Recent advances of non-fullerene organic electron transport materials in perovskite solar cells", J. Mater. Chem. A, 8, 20819, 2020 [Non-Patent Document 2] Nathalie Zink-Lorre et al., "Perylenediimides as more than just non-fullerene acceptors: versatile components in organic, hybrid and perovskite solar cells", Chem. Commun., 56, 3824, 2020 [Non-Patent Document 3] Jhao-lin Wu et al., "Simple mono-halogenated perylene diimides as non-fullerene electron transporting materials in inverted perovskite solar cells with ZnO nanoparticles cathode buffer layers", J. Mater. Chem. A, 8, 12811, 2017 Summary of the Invention [Problem to be solved by the invention]

[0006] However, perovskite solar cells using perylene diimide derivatives have 60 Compared with perovskite solar cells using fullerene derivatives, there was a problem that the conversion efficiency was likely to be low. For example, Non-Patent Document 3 compares the case where the electron transport layer is made of a perylene diimide derivative with the case where the electron transport layer is made of PCBM. Non-Patent Document 3 shows that the latter is far superior. In other words, the performance of perovskite solar cells using non-fullerene materials as the material for the electron transport layer is still insufficient, and further improvement is required.

[0007] The present invention has been made in view of the above problems. An object of the present invention is to provide a solar cell having a good conversion efficiency, which includes a metal halide perovskite compound in a photoelectric conversion layer, and a non-fullerene-based material in an electron transport layer, and a method for manufacturing the same. [Means for solving the problem]

[0008] The present invention provides a solar cell including a photoelectric conversion layer containing a metal halide perovskite compound, a first electron transport layer disposed on the photoelectric conversion layer, and a second electron transport layer disposed on the first electron transport layer, in which the first electron transport layer contains a 3,4,9,10-perylenetetracarboxylic acid diimide derivative represented by the following general formula (1), and the second electron transport layer contains one or more hole blocking compounds selected from the group consisting of a 1,10-phenanthroline derivative represented by the following general formula (2a) or (2b), a phenylpyridine derivative represented by the following general formula (2c), an organometallic complex having lithium or aluminum and an 8-quinolinol ligand, and a tin-containing conductive metal oxide. [ka] (In general formula (1), R 1 and R 2 each independently represents a linear or branched alkyl group having from 1 to 18 carbon atoms, or an aryl group having from 6 to 14 carbon atoms, which may have a substituent. [ka] (In the general formula (2a) or (2b), R 3 ~R 6 and R 11 ~R 17 each independently represents a hydrogen atom, a linear or branched alkyl group having from 1 to 10 carbon atoms, or an aryl group having from 6 to 20 carbon atoms which may have a substituent, and n represents 2 or 3. [ka] In the general formula (2c), Q represents an optionally substituted m-valent group represented by the following general formula: [ka] m is m 1 , m 2 , m 3 , and m 4(wherein m represents any one selected from the group consisting of 1 is an integer between 1 and 6, m 2 is an integer between 1 and 3, m 3 is an integer between 1 and 5, m 4 is an integer of 1 or more and 4 or less), X represents a phenylene group which may have a substituent, Z represents a pyridyl group which may have a substituent, p represents 1 or 2, and the substituents which Q, X, and Z may have are each independently a group selected from the group consisting of a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched monoalkylamino group having 1 to 6 carbon atoms, and a linear or branched dialkylamino group having 1 to 6 carbon atoms.

[0009] The present invention also provides a method for producing the above solar cell, the method including the steps of: preparing the photoelectric conversion layer; forming the first electron transport layer on the photoelectric conversion layer by vacuum deposition of a 3,4,9,10-perylene tetracarboxylic diimide derivative represented by the following general formula (1); and forming the second electron transport layer on the first electron transport layer. [ka] (In general formula (1), R 1 and R 2 each independently represents a linear or branched alkyl group having from 1 to 18 carbon atoms, or an aryl group having from 6 to 14 carbon atoms, which may have a substituent. Effect of the Invention

[0010] According to the present invention, there is provided a solar cell having a photoelectric conversion layer containing a metal halide perovskite compound, which has a good conversion efficiency even though the electron transport layer is made of a non-fullerene-based material. Also, according to the present invention, there is provided a manufacturing method for easily manufacturing the solar cell. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view of a solar cell according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view of a solar cell according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] In this specification, a numerical range indicated with "~" means a numerical range including the numerical values ​​written before and after "~".

[0013] The solar cell of the present invention will be described taking the following two embodiments as examples, however, the solar cell of the present invention is not limited to these embodiments.

[0014] 1. First embodiment FIG. 1 shows a schematic cross-sectional view of an example of a solar cell according to the first embodiment. As shown in FIG. 1, the solar cell 100 of this embodiment may have at least a photoelectric conversion layer 40 containing a metal halide perovskite compound, a first electron transport layer 51 arranged on one side of the photoelectric conversion layer 40, and a second electron transport layer 52 arranged on the first electron transport layer 51 (hereinafter, the first electron transport layer 51 and the second electron transport layer 52 are also collectively referred to as "electron transport layer 50"). The solar cell 100 of this embodiment further has a cathode layer 60 arranged on the second electron transport layer 52, a hole transport layer 30 arranged on the other side of the photoelectric conversion layer 40, an anode layer 20, and a substrate 10.

[0015] In the solar cell 100, sunlight is incident from the substrate 10 side, and the incident light generates electron-hole pairs in a metal halide perovskite compound (hereinafter also simply referred to as a "perovskite compound") in the photoelectric conversion layer 40. Then, the electrons generated in the perovskite compound move to the cathode layer 60 side via the electron transport layer 50, and the holes move to the anode layer 20 side via the hole transport layer 30, generating an electromotive force. Note that the solar cell 100 of this embodiment may further include layers and configurations other than those described above, as long as they do not impair the object and effect of this embodiment.

[0016] Here, in the solar cell 100 of this embodiment, the electron transport layer 50 has a first electron transport layer 51 containing a 3,4,9,10-perylenetetracarboxylic acid diimide derivative (hereinafter also simply referred to as a "perylene diimide derivative") having a specific structure, and a second electron transport layer 52 containing one or more specific hole blocking compounds. As described above, it is difficult to obtain sufficient conversion efficiency by only using a perylene diimide derivative as an electron transport material. In contrast, according to the intensive research of the present inventors, it has been found that a perovskite solar cell that is stable for a long period of time and has good conversion efficiency can be obtained by combining the perylene diimide derivative and a specific hole blocking material and laminating them. Hereinafter, each layer constituting the perovskite solar cell will be described.

[0017] (1)Electron transport layer As described above, the electron transport layer 50 of this embodiment includes the first electron transport layer 51 and the second electron transport layer 52. The electron transport layer 50 may include layers other than the first electron transport layer 51 and the second electron transport layer 52 as long as the object and effect of this embodiment are not impaired. However, in consideration of the manufacturing efficiency of the solar cell 100, its conversion efficiency, and the like, it is more preferable that the electron transport layer 50 is composed of the first electron transport layer 51 and the second electron transport layer 52.

[0018] About the first electron transport layer The first electron transport layer 51 is a layer that contains at least a 3,4,9,10-perylenetetracarboxylic acid diimide derivative (perylene diimide derivative) represented by the following general formula (1), and is disposed between the photoelectric conversion layer 40 and the cathode layer 60. In this embodiment, the first electron transport layer 51 is disposed adjacent to the photoelectric conversion layer 40. By disposing the first electron transport layer 51 adjacent to the photoelectric conversion layer 40, electrons generated in the photoelectric conversion layer 40 can be efficiently extracted.

[0019] The first electron transport layer 51 may contain only a perylene diimide derivative, or may further contain a component other than the perylene diimide derivative, as long as the object and effect of the present embodiment are not impaired. However, the total mass of the perylene diimide derivative in the first electron transport layer 51 is preferably 30 mass% or more, and more preferably 50 mass% or more, based on the total mass of the first electron transport layer 51. When the amount of the perylene diimide derivative in the first electron transport layer 51 is within this range, the photoelectric conversion efficiency of the solar cell 100 is likely to be improved. The first electron transport layer 51 may contain only one type of perylene diimide derivative represented by the following general formula (1), or may contain two or more types.

[0020] [ka] In the above general formula (1), R 1 and R 2 each independently represents a linear or branched alkyl group having from 1 to 18 carbon atoms, or an aryl group having from 6 to 14 carbon atoms which may have a substituent.

[0021] R 1 and R 2 The carbon number of the linear or branched alkyl group is preferably from 6 to 12, and more preferably from 8 to 12. Specific examples of the alkyl group include a 2-ethylhexyl group, an n-octyl group, and the like.

[0022] On the other hand, R 1 and R 2The number of carbon atoms of the aryl group which may have a substituent is preferably 6 to 12, more preferably 7 to 10. Examples of the substituent which the aryl group may have include an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms. The number of the substituent is appropriately selected according to the structure of the aryl group. Specific examples of the aryl group include a 4-methoxyphenyl group, a 3,5-dimethylphenyl group, and a 1-naphthyl group.

[0023] Preferred specific examples of the perylene diimide derivative include N,N'-bis(2-ethylhexyl)-3,4,9,10-perylene tetracarboxylic acid diimide represented by the following formula (1-1), N,N'-bis(n-octyl)-3,4,9,10-perylene tetracarboxylic acid diimide (abbreviation: PTCDI-C8) represented by the following formula (1-2), N,N'-bis(4-methoxyphenyl)-3,4,9,10-perylene tetracarboxylic acid diimide represented by the following formula (1-3), N,N'-bis(3,5-dimethylphenyl)-3,4,9,10-perylene tetracarboxylic acid diimide represented by the following formula (1-4), and N,N'-bis(1-naphthyl)-3,4,9,10-perylene tetracarboxylic acid diimide represented by the following formula (1-5). [ka]

[0024] Here, the thickness of the first electron transport layer 51 is preferably 1 nm or more and 100 nm or less, and more preferably 10 nm or more and 50 nm or less. When the thickness of the first electron transport layer is in this range, the photoelectric conversion characteristics of the solar cell 100 tend to be further improved.

[0025] - Second electron transport layer The second electron transport layer 52 is a layer disposed between the first electron transport layer 51 and the cathode layer 60, and is a layer mainly for moving electrons generated in the photoelectric conversion layer 40 to the cathode layer 60 and blocking holes from moving to the cathode layer 60. The second electron transport layer 52 only needs to contain a hole blocking compound described later, and may further contain components other than the hole blocking compound within a range that does not impair the object and effect of the present embodiment. However, the total mass of the hole blocking compound in the second electron transport layer 52 is preferably 30 mass% or more, more preferably 50 mass% or more, based on the total mass of the second electron transport layer 52. When the amount of the hole blocking compound in the second electron transport layer 52 is within this range, the photoelectric conversion efficiency of the solar cell 100 is likely to be improved. The second electron transport layer 52 may contain only one type of the hole blocking compound described below, or may contain two or more types.

[0026] Here, the hole-blocking compound is a compound selected from the group consisting of 1,10-phenanthroline derivatives represented by the following general formula (2a) or (2b), phenylpyridine derivatives represented by the following general formula (2c), organometallic complexes having lithium or aluminum and an 8-quinolinol ligand, and conductive metal oxides containing tin. These hole-blocking compounds exhibit excellent hole-blocking properties when combined with the perylene diimide derivative.

[0027] The following shows 1,10-phenanthroline derivatives represented by general formula (2a) or (2b), which can be hole-blocking compounds. As shown below, the phenanthroline derivative may have only one phenanthroline-derived structure in the molecule, or may have two or more phenanthroline-derived structures. [ka] In the above general formula (2a) or (2b), R 3 ~R 6 and R 11 ~R 17Each of R independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms which may have a substituent. 3 ~R 6 and R 11 ~R 17 The number of carbon atoms of the linear or branched alkyl group that may be R is preferably 1 to 12, more preferably 1 to 8. Examples of the alkyl group include a methyl group, an ethyl group, and a butyl group. 3 ~R 6 and R 11 ~R 17 The number of carbon atoms in the aryl group is preferably 6 or more and 14 or less, more preferably 6 or more and 10 or less. Examples of the substituent that the aryl group may have include an alkyl group having 1 or more and 10 or less carbon atoms, an alkoxy group having 1 or more and 10 or less carbon atoms, an amino group, a nitro group, and the like. Specific examples of the aryl group include a phenyl group, a 4-methylphenyl group, a 1-naphthyl group, a 2-naphthyl group, and the like. In addition, n in the above general formula (2b) represents 2 or 3, and is preferably 2.

[0028] Specific examples of 1,10-phenanthroline derivatives containing only one phenanthroline-derived structure include 2,9-bis(naphthalen-1-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: α-NBPhen) represented by the following formula (2a-1), 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: β-NBPhen) represented by the following formula (2a-2), and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (abbreviation: baxoproine BCP) represented by the following formula (2a-3). [ka]

[0029] Specific examples of 1,10-phenanthroline derivatives containing two or more phenanthroline-derived structures include compounds represented by the following chemical formula: [ka]

[0030] Furthermore, specific examples of the 1,10-phenanthroline derivatives include the compounds described in JP-A-2008-222624.

[0031] Among the above 1,10-phenanthroline derivatives, β-NBPhen and α-NBPhen are preferred from the viewpoint of easily achieving particularly good conversion efficiency.

[0032] The phenylpyridine derivatives represented by the general formula (2c) which may be the hole-blocking compounds are shown below. [ka]

[0033] In the above general formula (2c), Q represents a group having a valence of m, which may have a substituent, and which is represented by the following general formula: Here, m is appropriately selected depending on the structure of the group represented by Q, and m 1 , m 2 , m 3 , and m 4 It is any one selected from the group consisting of: [ka] m 1 is an integer of 1 to 6, preferably 1 to 3. 2 is an integer of 1 or more and 3 or less, and preferably 1 or more and 3 or less. 3 is an integer of 1 to 5, preferably 1 to 3. 4 is an integer of 1 or more and 4 or less, and preferably 1 or more and 2 or less.

[0034] The substituent that the group represented by Q may have is a group selected from the group consisting of a linear or branched alkyl group having from 1 to 6 carbon atoms, a linear or branched alkoxy group having from 1 to 6 carbon atoms, and a linear or branched monoalkylamino group or dialkylamino group having from 1 to 6 carbon atoms. The upper limit of the number of the substituents is appropriately selected according to the structure of the group represented by Q.

[0035] On the other hand, X in the general formula (2c) represents a phenylene group which may have a substituent. The substituent which the group represented by X may have is a group selected from the group consisting of a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, and a linear or branched monoalkylamino group or dialkylamino group having 1 to 6 carbon atoms. The upper limit of the number of the substituents is appropriately selected according to the structure of the group represented by Q. The upper limit of the number of the substituents is 4, and more preferably 2 or less.

[0036] Z in the above general formula (2c) represents a pyridyl group which may have a substituent. The substituent which the group represented by Z may have is a group selected from the group consisting of a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, and a linear or branched monoalkylamino group or dialkylamino group having 1 to 6 carbon atoms. The upper limit of the number of the substituents is appropriately selected according to the structure of the group represented by Q. The upper limit of the number of the substituents is 5, and more preferably 3 or less. In addition, p in the above general formula (2c) is 1 or 2.

[0037] Specific examples of the phenylpyridine derivative represented by the above general formula (2c) include 4,6-bis(3,5-di(pyridin-3-yl)phenyl)-2-methylpyrimidine (abbreviation: B3PyMPM) represented by the following formula (2c-1), 4,6-bis(3,5-di(pyridin-4-yl)phenyl)-2-methylpyrimidine (abbreviation: B4PyMPM) represented by the following formula (2c-2), and 1,3,5-tris(p-pyridyl-3-yl-phenyl)benzene (abbreviation: TpPyPB) represented by the following formula (2c-3). [ka]

[0038] Further, specific examples of the phenylpyridine derivatives include the compounds described in JP-A-2008-127326 and JP-A-2009-35524.

[0039] Among the above phenylpyridine derivatives, B3PyMPM and TpPyPB are preferable from the viewpoint of easily obtaining particularly good conversion efficiency.

[0040] Examples of organometallic complexes having lithium or aluminum and an 8-quinolinol ligand, which may be the hole-blocking compound, include 8-quinolinolatolithium (Liq) represented by the following formula (2d-1) and tris(8-quinolinolato)aluminum (Alq) represented by the following formula (2d-2). These compounds may have a substituent. Examples of the substituent include an alkyl group having 1 to 4 carbon atoms; an aryl group such as a phenyl group or a naphthyl group; and combinations thereof. [ka]

[0041] Examples of conductive metal oxides containing tin that may be the hole-blocking compound include tin oxide (SnO 2 ), fluorine-doped tin oxide (abbreviated as FTO), tungsten-doped tin oxide, etc.

[0042] The second electron transport layer 52 may further contain a compound described in JP-A-2007-15993 or a compound described in JP-A-2008-214339.

[0043] Here, the thickness of the second electron transport layer 52 containing the hole blocking compound is preferably 1 nm to 100 nm, more preferably 1 nm to 50 nm. When the thickness of the second electron transport layer is within this range, the hole blocking property of the second electron transport layer 52 becomes even better, and the photoelectric conversion characteristics of the solar cell 100 tend to become even better.

[0044] (2) Photoelectric conversion layer The photoelectric conversion layer 40 is a layer containing a metal halide perovskite organic compound (perovskite compound), which generates electrons and holes when irradiated with light. The perovskite compound is represented by the general formula AB m X n In the general formula, A is an organic group MA (methylammonium (CH 3 NH 3 + )), organic group FA (formamidinium (HC(NH 2 ) 2 + )), Cesium cation (Cs + ), potassium cation (K + ), rubidium cation (Rb + ) In addition, B in the general formula represents the metal ion Pb 2+ Or Sn 2+ Furthermore, X in the general formula represents a halogen ion F - , Cl - , I - , or Br -In addition, m is 0.8 to 1.2, and n is 2.8 to 3.2. The photoelectric conversion layer 40 may contain only one type of the perovskite compound, or may contain two or more types. In addition, the photoelectric conversion layer 40 may contain components other than the perovskite compound within a range that does not impair the object and effect of this embodiment, but the total mass of the perovskite compound in the photoelectric conversion layer is preferably 60 mass % or more, more preferably 90 mass % or more, based on the total mass of the photoelectric conversion layer. When the amount of the hole blocking compound in the photoelectric conversion layer 40 is within this range, the photoelectric conversion efficiency of the solar cell 100 is likely to be improved.

[0045] The thickness of the photoelectric conversion layer 40 is appropriately selected depending on the light absorption of the photoelectric conversion layer, but is preferably 100 nm to 1 μm, and more preferably 300 nm to 800 nm. When the thickness of the photoelectric conversion layer 40 is in this range, it can efficiently absorb sunlight and generate a higher electromotive force.

[0046] In the photoelectric conversion layer 40, the surface on the first electron transport layer 51 side may be passivated, or both surfaces of the photoelectric conversion layer 40 may be passivated. The method for passivating the photoelectric conversion layer 40 is not particularly limited, but includes treatment with glycine hydrochloride, treatment with ethylenediamine diiodide hydroxide, and treatment with 2-phenylethylamine hydrochloride.

[0047] (3) Cathode layer There is no particular limitation on the structure or type of the cathode layer 60 as long as it is possible to extract a current to the outside. The cathode layer 60 of this embodiment has a conductive film 61 made of a metal conductive film or a light-transmitting film arranged on the entire surface of the above-mentioned electron transport layer 50 so as to cover the layer, and an auxiliary electrode 62 arranged in a pattern on the conductive film 61.

[0048] When the cathode layer 60 (conductive film 61) has optical transparency, light can be incident on the photoelectric conversion layer 40 from the cathode layer 60 side in the solar cell 100. However, if the cathode layer 60 is only the transparent conductive film 61, the series resistance may increase when the solar cell 100 is enlarged. Therefore, when using the transparent conductive film 61 having optical transparency, it is preferable to use the conductive film 61 in combination with the auxiliary electrode 62 having high electrical conductivity as in this embodiment. In this specification, having optical transparency means that the transmittance of light of any wavelength between 200 nm and 1500 nm is 10% or more. On the other hand, when the conductive film 61 has a sufficiently high electrical conductivity, such as when the conductive film 61 is a metal film, the auxiliary electrode 62 is not necessarily required.

[0049] Examples of materials constituting the auxiliary electrode 62 include platinum, gold, silver, copper, aluminum, magnesium, rhodium, indium, titanium, iron, nickel, tin, zinc, palladium, and alloys thereof. The pattern and thickness of the auxiliary electrode 62 are appropriately selected depending on the application of the solar cell 100, the light receiving area, etc.

[0050] On the other hand, examples of materials constituting the conductive film 61 include the same metals as those of the auxiliary electrode 62, or metal oxides having electrical conductivity and optical transparency. Examples of metal oxides include oxides of indium, zinc, or alloys thereof. Specifically, indium oxide (In 2 O 3 Or In 2 O 3 Indium oxides such as indium tin oxide (ITO), indium tin oxide containing silicon or silicon oxide (ITSO), indium zinc oxide (IZO), indium oxide containing tungsten oxide and zinc oxide (IWZO); zinc oxides such as zinc oxide (ZnO), zinc oxide doped with gallium (GZO), and zinc oxide containing aluminum (AZO); tin oxide containing fluorine (SnO 2 ) (abbreviation: FTO), and tin oxide such as tungsten-containing tin oxide. The transparent conductive film may be composed of one layer of these, or may be a laminate of two or more layers.

[0051] The thickness of the conductive film 61 is not particularly limited as long as it can exhibit sufficient conductivity, and is preferably 10 nm to 1 μm, and more preferably 50 nm to 600 nm. On the other hand, the thickness of the auxiliary electrode 62 is not particularly limited as long as it can exhibit sufficient conductivity, and is preferably 1 μm to 500 μm, and more preferably 5 μm to 30 μm.

[0052] (4) Hole transport layer The hole transport layer 30 is a layer for transferring holes generated in the photoelectric conversion layer 40 to the anode layer 20 side and suppressing the movement of electrons generated in the photoelectric conversion layer 40 to the anode layer 20 side. The hole transport layer 13 may be any layer containing a hole transport material.

[0053] Examples of hole transport materials include [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (abbreviation: MeO-2PACz), [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid (abbreviation: MeO-4PACz), [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (abbreviation: 2PACz), [2-(3,6-dibromo-9H-carbazol-9-yl)ethyl]phosphonic acid (abbreviation: Self-assembled monolayer materials having phosphonic acids such as [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphonic acid (abbreviation: Me-2PACz), [4-(9H-carbazol-9-yl)butyl]phosphonic acid (abbreviation: 4PACz) and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (abbreviation: Me-4PACz); nickel oxide (NiO x ), tungsten oxide (WO x), metal oxides such as aluminum oxide (AlO); and organic semiconductors such as poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (abbreviation: PTAA), poly[(9,9-dictylfluorenyl-2,7-diyl)-co-(4,4'(N-(4-sec-butylphenyl)diphenylamine)) (abbreviation: TFB), and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (abbreviation: PEDOT:PSS). The hole transport layer 30 may contain only one of these, or may contain two or more of them. In addition, the hole transport layer 30 may be composed of a single layer, or may be composed of multiple layers of the same or different types.

[0054] The thickness of the hole transport layer 30 is not particularly limited as long as it can exhibit the above-mentioned hole transport performance, and is preferably 1 μm or less, more preferably 100 nm or less.

[0055] (5)Anode layer The anode layer 20 is not particularly limited in structure or type as long as it can extract a current to the outside. The anode layer 20 of this embodiment has a transparent conductive film 21 having light transmission, which is disposed between the substrate 10 and the hole transport layer 30, and an auxiliary electrode 22 arranged in a pattern on the transparent conductive film 21. In this embodiment, the auxiliary electrode 22 is disposed at a position that does not overlap with the photoelectric conversion layer 40, so that the auxiliary electrode 22 does not need to have light transmission. The auxiliary electrode 22 can be made of a metal material or a carbon material. Examples of metals include platinum, gold, silver, copper, aluminum, rhodium, indium, titanium, iron, nickel, tin, zinc, and alloys thereof. The pattern and thickness of the auxiliary electrode 22 are appropriately selected according to the application, structure, etc. of the solar cell 100.

[0056] On the other hand, the transparent conductive film 21 may be a film having optical transparency and electrical conductivity. Examples of materials for the transparent conductive film 21 include metal oxides. Examples of metal oxides include metal oxides including indium, zinc, or alloys thereof. Specifically, indium oxide (In 2 O 3 Or In2 O 3 Indium oxides such as indium tin oxide (ITO), indium oxide containing fluorine (FTO), indium tin oxide containing silicon or silicon oxide (ITSO), indium oxide containing tungsten oxide and zinc oxide (IWZO); zinc oxides such as zinc oxide (ZnO), zinc oxide containing gallium (GZO), and zinc oxide containing aluminum (AZO); tin oxide (SnO 2 ); and the like. The transparent conductive film may be composed of one of these layers, or may be a laminate of two or more layers. The transparent conductive film 21 may contain only one of these layers, or may contain two or more types.

[0057] The thickness of the transparent conductive film 21 is not particularly limited as long as it can exhibit sufficient conductivity, but it is preferable to adjust the sheet resistance value to be 5 Ω / □ or more and 15 Ω / □ or less.

[0058] (6) Substrate The substrate 10 may be transparent to sunlight and strong enough to support the above-mentioned components. Examples of materials for the substrate 10 include inorganic materials such as soda glass, and light-transmitting resin materials such as fluororesins and polyimides.

[0059] (7) Manufacturing method of solar cell The solar cell 100 of the first embodiment described above can be manufactured, for example, by the following method, however, the manufacturing method of the solar cell 100 is not limited to this method.

[0060] In the method for manufacturing the solar cell 100, the anode layer 20 (transparent conductive film 21 and auxiliary electrode 22) is formed on the substrate 10 by a known method. The method for forming the anode layer 21 is not particularly limited. For example, an ink in which the above-mentioned metal or metal oxide is dissolved or dispersed in a liquid is prepared, and the ink is applied by various application methods or the like, and the liquid is removed to form the anode layer 21. Alternatively, the anode layer 21 may be formed by forming a film of the above-mentioned metal oxide by a sputtering method, a vacuum deposition method, or the like.

[0061] Subsequently, a hole transport layer 30 containing the above-mentioned hole transport material is formed on the anode layer 21. There is no particular limitation on the method for forming the hole transport layer 30. For example, the hole transport layer 30 can be formed by dissolving or dispersing the hole transport material in a liquid, applying the liquid by a known application method (e.g., spin coating), and then removing the liquid.

[0062] A photoelectric conversion layer 40 containing the above-mentioned perovskite compound is further formed on the hole transport layer 13. The method of forming the photoelectric conversion layer 40 is not particularly limited, but it is preferable to form it by solution coating, vacuum deposition, or both methods. In the solution coating method, a composition in which the perovskite compound is dissolved or dispersed in a liquid is applied by a spin coating method, a slit coating method, a die coating method, a spray coating method, a roll coating method, or the like, and then a precursor layer is formed by a poor solvent method, a vacuum quenching method, a gas quenching method, or the like. Furthermore, this precursor layer is subjected to a heat treatment at 50°C or more and 200°C or less. According to this method, the perovskite compound in the precursor layer is crystallized, and the photoelectric conversion layer 40 is formed.

[0063] On the photoelectric conversion layer 40, the above-mentioned perylene diimide derivative is formed into a film by various methods to form the first electron transport layer 51. The first electron transport layer 51 is preferably formed by a vacuum deposition method such as a vacuum thermal deposition method. When the first electron transport layer 51 is formed by these methods, impurities are unlikely to be included in the first electron transport layer 51, and the film thickness is easy to control. In other words, a layer with excellent electron transport properties is easily obtained.

[0064] Subsequently, the above-mentioned hole blocking compound is formed on the first electron transport layer 51 to form the second electron transport layer 52. The method for forming the second electron transport layer 52 is appropriately selected depending on the type of the hole blocking compound, and examples thereof include a vacuum deposition method, a solution coating method, an atomic layer deposition (ALD) method, a sputtering method, and the like.

[0065] The method of forming the cathode layer 60 on the second electron transport layer 52 is not particularly limited, and may be, for example, a metal constituting the conductive film 61 formed by a vapor deposition method, a metal oxide or the like formed by a sputtering method, or a solution containing nanoparticles applied. The method of forming the auxiliary electrode 62 is also not particularly limited. The auxiliary electrode 62 may be formed by a known method. After the cathode layer 60 is formed, it may be heat-treated in the air or in argon or nitrogen at a temperature in the range of 50°C to 200°C, if necessary.

[0066] (8) Variations In the above, a solar cell in which sunlight is incident from the anode layer 20 (substrate 10) side has been described. However, the solar cell of the present invention may be configured so that sunlight is incident from the cathode layer 60 side, or may be configured so that sunlight is incident from both the anode layer 20 (substrate 10) side and the cathode layer 60 side. In this case, it is preferable that the conductive film 61 of the above-mentioned cathode layer 60 is a transparent conductive film having optical transparency.

[0067] In the above, the substrate 10 is disposed on the anode layer 20 side, but the substrate 10 may be disposed on the cathode layer 60 side.

[0068] 2. Second embodiment The solar cell of the second embodiment further includes a second photoelectric conversion layer containing crystalline silicon in addition to the configuration of the solar cell 100 of the first embodiment described above. That is, the solar cell has a tandem structure in which a perovskite solar cell and a crystalline silicon solar cell are stacked. By including the second photoelectric conversion layer containing crystalline silicon in the solar cell, it is possible to perform photoelectric conversion more efficiently by utilizing light of a wavelength that is not absorbed by the photoelectric conversion layer containing the perovskite compound described above. The crystalline silicon solar cell may be connected in series or in parallel with the perovskite solar cell (the solar cell 100 of the first embodiment).

[0069] FIG. 2 shows a schematic cross-sectional view of an example of the solar cell of this embodiment. However, the structure of the solar cell of this embodiment is not limited to this structure. In the solar cell 200, a back electrode 90 / second semiconductor layer 72 / semiconductor substrate (second photoelectric conversion layer) 80 / first semiconductor layer 71 / anode layer 20 (transparent conductive film 21) / hole transport layer 30 / photoelectric conversion layer 40 / first electron transport layer 51 / second electron transport layer 52 / cathode layer 60 (conductive film 61 and auxiliary electrode 62) are laminated in this order, and sunlight is incident from the cathode layer 60 side. In the solar cell 200 of this embodiment, the same members as those of the solar cell 100 of the first embodiment described above are given the same reference numerals, and the description here is omitted.

[0070] The semiconductor substrate (second photoelectric conversion layer) 80 of the solar cell 200 may contain crystalline silicon, and may be, for example, a p-type single crystal silicon substrate doped with boron, gallium, or the like, or an n-type single crystal silicon substrate doped with phosphorus. The semiconductor substrate 80 is similar to the semiconductor substrate of a known single crystal silicon solar cell.

[0071] In addition, the first semiconductor layer 71 and the second semiconductor layer 72 in this embodiment are an n-type semiconductor layer and a p-type semiconductor layer, respectively. When the first semiconductor layer 71 is an n-type amorphous silicon layer, the second semiconductor layer 72 is a p-type amorphous silicon layer. Note that an undoped amorphous silicon layer (not shown) may be disposed between the first semiconductor layer 71 and / or the second semiconductor layer 72 and the semiconductor substrate 80. The first semiconductor layer 71 and the second semiconductor layer 72, and the undoped amorphous silicon layer are similar to the p-type, n-type, or i-type amorphous silicon layers of known single crystal silicon solar cells.

[0072] Furthermore, when the first semiconductor layer 71 is an n-type crystalline silicon layer, the second semiconductor layer 72 is a p-type crystalline silicon layer. An oxide film (silicon oxide film or aluminum oxide film) or an insulating film (nitride film) may be formed between the first semiconductor layer 71 and / or the second semiconductor layer 72 and the semiconductor substrate 80. The first semiconductor layer 71 and the second semiconductor layer 72 are similar to the p-type and n-type layers of known crystalline silicon solar cells.

[0073] In addition, the back electrode 90 of the present embodiment is not particularly limited in structure or type as long as it is capable of extracting a current to the outside. Examples of materials constituting the back electrode 90 include silver, aluminum, rhodium, indium, titanium, iron, nickel, tin, zinc, and alloys thereof.

[0074] -Solar cell manufacturing method The solar cell 200 of the second embodiment described above can be manufactured, for example, by the following method, but is not limited to this method.

[0075] A desired semiconductor substrate (n-type or p-type single crystal silicon substrate) 80 is prepared, and non-doped amorphous silicon layers are formed on both sides of the semiconductor substrate 80 by plasma enhanced chemical vapor deposition (PECVD) or chemical vapor deposition (CVD) using a catalyst. Then, an n-type amorphous silicon layer doped with phosphorus is deposited on one side, and a p-type amorphous silicon layer doped with boron is deposited on the other side, thereby forming the first semiconductor layer 71 and the second semiconductor layer 72. There are no particular limitations on the method of doping with phosphorus or boron, and the doping can be performed during the formation of the amorphous silicon film, or by ion implantation.

[0076] Subsequently, the above-mentioned back electrode 90 is formed on the second semiconductor layer 72 by vacuum thermal evaporation, sputtering, screen printing, or the like.

[0077] Furthermore, the anode layer 20 / hole transport layer 30 / photoelectric conversion layer 40 / first electron transport layer 51 / second electron transport layer 52 / cathode layer 60 (transparent conductive film 61 and auxiliary electrode 62) are formed in this order on the first semiconductor layer 71 by the method described in the above-mentioned first embodiment. Note that an oxide film (silicon oxide film or aluminum oxide film) or an insulating film (nitride film) may be formed between the first semiconductor layer 71 and the anode layer 20. In this way, the solar cell 200 of this embodiment is obtained.

[0078] 3.Other The above-mentioned solar cell 100 can be modularized by sealing with a sealing material or the like. The structure and material of the sealing material for the solar cell are not particularly limited as long as it can protect the solar cell from oxygen, water, etc. Examples of the sealing material include a glass cap, a plastic film with gas barrier properties, an organic thin film or an inorganic thin film with gas barrier properties, or a laminate of these. EXAMPLES

[0079] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited thereto.

[0080] <Material preparation> The following materials and compositions were prepared to form a solar cell. All materials were stored in a dry nitrogen environment until immediately before use.

[0081] Hole transport layer forming solution: 1 mM solution of [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz) (Tokyo Chemical Industry Co., Ltd.) in ethanol (Fujifilm Wako Co., Ltd.) Photoelectric conversion layer forming solution: Perovskite compound solution prepared by the method described below C 60 Fullerene (Sigma-Aldrich) Antisolvent: Anisole (manufactured by Fujifilm Wako Co., Ltd.) Perylene diimide derivatives: N,N'-bis(2-ethylhexyl)-3,4,9,10-perylenetetracarboxylic diimide (manufactured by Chemipro Chemicals) Hole-blocking compounds: BCP (TCI) α-NBPhen (manufactured by Chemipro Chemicals) β-NBPhen (manufactured by Chemipro Chemicals) B3PyMPM (manufactured by Chemipro Chemicals) TpPyPB (manufactured by Chemipro Chemicals) 8-Quinolinolatoaluminum (Alq3) (manufactured by Chemipro Chemicals) Passivation materials: Glycine hydrochloride (Tokyo Chemical Industry Co., Ltd.) and ethylenediamine dihydroiodide (EDAI2) (Tokyo Chemical Industry Co., Ltd.)

[0082] (Method for preparing a perovskite compound solution) Formamidine hydroiodide (FAI), lead(II) iodide (PbI) were dissolved in a mixture of N,N-dimethylformamide (DMF) (Fujifilm Wako Co., Ltd.) and dimethyl sulfoxide (DMSO) (Fujifilm Wako Co., Ltd.) in a volume ratio of 4:1. 2 ), methylammonium bromide (MABr), lead bromide (PbBr 2 ) (both manufactured by Tokyo Chemical Industry Co., Ltd.) and cesium iodide (CsI) (manufactured by Sigma-Aldrich) were dissolved in the solution. Then, a perovskite compound (Cs 0.05 (FA 0.76 MA 0.24 ) 0.95 Pb(I 0.76 / Br 0.24 ) 3 ) solution was prepared.

[0083] <Fabrication of solar cells> [Comparative Example 1] Preparation of a substrate with an anode (transparent conductive film) A glass substrate having a transparent conductive film made of an indium tin oxide (ITO) film was prepared. The glass substrate with the transparent conductive film was immersed in a surfactant aqueous solution, water, acetone, and 2-propanol in that order, and ultrasonically cleaned for 30 minutes each. After cleaning, it was dried at 60°C for 16 hours, and the surface was further modified in an ultraviolet-ozone surface modification device for 30 minutes. Then, it was immediately transported to a dry nitrogen environment.

[0084] Formation of hole transport layer A solution for forming a hole transport layer, which forms a self-assembled monolayer, was applied onto the transparent conductive film of the glass substrate with the transparent conductive film by a spin coater. Then, the solution was heat-treated at 100° C. for 10 minutes to obtain a hole transport layer.

[0085] Formation of photoelectric conversion layer The above-mentioned perovskite compound solution was dropped onto the hole transport layer, and anisole was dropped as a poor solvent at an appropriate timing. This caused the perovskite compound in the perovskite compound solution to start crystallizing. After that, a photoelectric conversion layer (perovskite layer) was obtained by heat treatment at 100°C for 10 minutes.

[0086] Formation of electron transport layer (single layer) On the photoelectric conversion layer, N,N'-bis(2-ethylhexyl)-3,4,9,10-perylenetetracarboxylic diimide was vacuum-deposited to a thickness of 30 nm to obtain an electron transport layer (single layer).

[0087] Cathode layer formation Silver was vacuum-deposited on the electron transport layer to form a cathode layer, thereby obtaining a solar cell.

[0088] [Example 1] A solar cell was produced in the same manner as in Comparative Example 1, except that the electron transport layer was produced by the following method.

[0089] Formation of electron transport layer (2 layers) On the photoelectric conversion layer, N,N'-bis(2-ethylhexyl)-3,4,9,10-perylenetetracarboxylic diimide was vacuum-deposited to a thickness of 30 nm to form a first electron transport layer, and then BCP was vacuum-deposited to a thickness of 8 nm on the first electron transport layer to form a second electron transport layer.

[0090] [Example 2] A solar cell was produced in the same manner as in Example 1, except that the material for the second electron transport layer was β-NBPhen.

[0091] [Example 3] A solar cell was produced in the same manner as in Example 1, except that the material for the second electron transport layer was α-NBPhen.

[0092] [Example 4] A solar cell was produced in the same manner as in Example 1, except that the material of the second electron transport layer was B3PyMPM.

[0093] [Example 5] A solar cell was fabricated in the same manner as in Example 1, except that the material of the second electron transport layer was TpPyPB.

[0094] [Example 6] A solar cell was fabricated in the same manner as in Example 1, except that the material of the second electron transport layer was changed to Alq3.

[0095] [Reference example 1] As the first electron transport layer, C was used instead of the 3,4,9,10-perylenetetracarboxylic diimide derivative. 60 A solar cell was produced in the same manner as in Example 1, except that fullerene was vapor-deposited.

[0096] [Reference example 2] As the first electron transport layer, C was used instead of the 3,4,9,10-perylenetetracarboxylic diimide derivative. 60 A solar cell was produced in the same manner as in Example 2, except that fullerene was vapor-deposited.

[0097] [Reference example 3] As the first electron transport layer, C was used instead of the 3,4,9,10-perylenetetracarboxylic diimide derivative. 60 A solar cell was produced in the same manner as in Example 3, except that fullerene was vapor-deposited.

[0098] [evaluation] Characteristics measurement A current probe and a voltage probe for measurement were placed in contact with the solar cell produced in each of the examples and comparative examples, and artificial sunlight was irradiated from the glass substrate side to measure the current-voltage characteristics during power generation using the four-terminal method. The results are shown in Table 1 below. In this specification, the positive voltage sweep direction is referred to as the forward sweep, and the negative voltage sweep direction is referred to as the reverse sweep.

[0099] [result] [Table 1]

[0100] As shown in Table 1 above, in Examples 1 to 6 in which the first electron transport layer contains a perylene diimide derivative and the second electron transport layer contains a specific hole blocking compound, the conversion efficiency was higher than that of Comparative Example 1, which does not have a second electron transport layer, and the conversion efficiency exceeded 15%. 60 When compared with the reference example using fullerene, no significant difference in performance was observed. For example, Example 3 in which the first electron transport layer contains perylene diimide and the second electron transport layer contains α-NBPhen and Example 4 in which the first electron transport layer contains C 60 In comparison with Reference Example 3, in which the second electron transport layer contains α-NBPhen and the fullerene is contained therein, the fill factor of Example 3 was somewhat inferior, but the short circuit current and open circuit voltage showed almost the same values. In other words, by using a solar cell having the configuration of the present invention, it is possible to reduce the cost and the air resistance of C 60 It can be said that solar cells with good characteristics can be obtained even without using fullerene as a material for the electron transport layer. Furthermore, by optimizing the manufacturing process of solar cells, further improvement in conversion efficiency can be expected.

[0101] [Example 7] A solar cell was produced in the same manner as in Example 2, except that after the formation of the photoelectric conversion layer and before the formation of the first electron transport layer, the photoelectric conversion layer was passivated using glycine hydrochloride and EDAI2.

[0102] [Example 8] A solar cell was produced in the same manner as in Example 3, except that after the formation of the photoelectric conversion layer and before the formation of the first electron transport layer, the photoelectric conversion layer was passivated using glycine hydrochloride and EDAI2.

[0103] [Reference example 4] A solar cell was produced in the same manner as in Reference Example 1, except that after the formation of the photoelectric conversion layer and before the formation of the first electron transport layer, the photoelectric conversion layer was passivated using glycine hydrochloride and EDAI2.

[0104] [evaluation] Characteristics measurement The solar cells produced in each of the Examples and Comparative Examples were contacted with the measurement current probe and voltage probe in the same manner as described above, and the solar cell was irradiated with simulated sunlight from the glass substrate side to measure the current-voltage characteristics during power generation using the four-terminal method. The results are shown in Table 2 below. Table 2 also shows the results when no passivation was performed (the results of Examples 2 and 3, and Reference Example 1).

[0105] [Table 2]

[0106] As shown in Table 2 above, it was revealed that the performance of the solar cell was further improved by passivating the surface of the photoelectric conversion layer on the side of the first electron transport layer (comparison of Examples 7 and 8 with Examples 2 and 3). In addition, the results of Examples 7 and 8 were better than those of Reference Example 1 (wherein the first electron transport layer is C), which had the best performance among the above-mentioned Reference Examples 1 to 3. 60The results were better than those of a solar cell including a fullerene and a second electron transport layer including BCP, and those of Reference Example 4 in which the photoelectric conversion layer of Reference Example 1 was passivated. Therefore, it was demonstrated that the solar cell of the present invention is also effective in increasing the efficiency of a solar cell module. [Industrial Applicability]

[0107] According to the present invention, a solar cell containing a metal halide perovskite compound in a photoelectric conversion layer is provided that is stable over time and has good conversion efficiency, even though the electron transport layer is made of a non-fullerene-based material. The solar cell can be easily manufactured and can be used for various purposes. [Explanation of symbols]

[0108] 10 Substrate 20 Anode layer 21 Transparent conductive film 22 Auxiliary electrode 30 Hole transport layer 40 Photoelectric conversion layer 50 Electron transport layer 51 First electron transport layer 52 Second electron transport layer 60 Cathode Layer 61 Conductive Film 62 Auxiliary electrode 71 First semiconductor layer 72 Second semiconductor layer 80 Semiconductor Substrate 90 Back electrode 100, 200 solar cells

Claims

1. A photoelectric conversion layer including a metal halide perovskite compound; a first electron transport layer disposed on the photoelectric conversion layer; a second electron transport layer disposed on the first electron transport layer; A solar cell comprising: The first electron transport layer contains a 3,4,9,10-perylenetetracarboxylic acid diimide derivative represented by the following general formula (1): the second electron transport layer contains one or more hole blocking compounds selected from the group consisting of 1,10-phenanthroline derivatives represented by the following general formula (2a) or (2b), phenylpyridine derivatives represented by the following general formula (2c), organometallic complexes having lithium or aluminum and an 8-quinolinol ligand, and conductive metal oxides containing tin: Solar cell. 【Chemistry 1】 (In general formula (1), R １ and R ２ each independently represents a linear or branched alkyl group having from 1 to 18 carbon atoms, or an aryl group having from 6 to 14 carbon atoms which may have a substituent. 【Chemistry 2】 (In the general formula (2a) or (2b), R ３ ~R ６ and R １１ ~R １７ each independently represents a hydrogen atom, a linear or branched alkyl group having from 1 to 10 carbon atoms, or an aryl group having from 6 to 20 carbon atoms which may have a substituent, n represents 2 or 3. 【Chemistry 3】 (In general formula (2c), Q represents an m-valent group represented by the following general formula, which may have a substituent: 【Chemistry 4】 m is m １ , m ２ , m ３ , and m ４ (wherein m represents any one selected from the group consisting of １ is an integer of 1 to 6, m ２ is an integer of 1 to 3, m ３ is an integer of 1 to 5, m ４ is an integer between 1 and 4, X represents a phenylene group which may have a substituent; Z represents a pyridyl group which may have a substituent; p represents 1 or 2; The substituents that Q, X, and Z may have are each independently a group selected from the group consisting of a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched monoalkylamino group having 1 to 6 carbon atoms, and a linear or branched dialkylamino group having 1 to 6 carbon atoms.

2. The surface of the photoelectric conversion layer on the first electron transport layer side is passivated. The solar cell according to claim 1 .

3. Further comprising a second photoelectric conversion layer comprising crystalline silicon; The solar cell according to claim 1 .

4. A method for producing the solar cell according to claim 1, preparing the photoelectric conversion layer; forming a film of a 3,4,9,10-perylenetetracarboxylic diimide derivative represented by the following general formula (1) on the photoelectric conversion layer by vacuum deposition to form the first electron transport layer; forming the second electron transport layer on the first electron transport layer; Including, A method for manufacturing solar cells. 【Chemistry 5】 (In general formula (1), R １ and R ２ each independently represents a linear or branched alkyl group having from 1 to 18 carbon atoms, or an aryl group having from 6 to 14 carbon atoms which may have a substituent.

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