Photoelectric conversion element, photoelectric conversion module, electronic device, and power supply module

Abstract

A photoelectric conversion element comprising: a first carrier; a first electrode; an electron transport layer; a photoelectric conversion layer; a hole transport layer; and a second electrode, wherein the hole transport layer comprises: a polymer comprising a repeating unit of the following general formula (1), and a compound of the general formula (2): wherein in the general formula (1), Ar1 represents an aromatic hydrocarbon, which may have a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon, a non-condensed polycyclic aromatic hydrocarbon, or a condensed polycyclic aromatic hydrocarbon, which may have a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may have a substituent; R1 to R4 each independently represent hydrogen, an alkyl group, or an aryl group; and n represents an integer of 2 or greater that allows the polymer of the general formula (1) to have a weight average molecular weight of 2,000 or greater; and in the general formula (2), R5 to R9 may be the same or different and represent hydrogen, a halogen, an alkyl group, an alkoxy group, or an aryl group; and X represents a cation. #imgabs0#

Description

Technical Field

[0001] The present disclosure relates to a photoelectric conversion element, a photoelectric conversion module, an electronic device, and a power supply (power supply, powersupply) module. Background Art

[0002] In recent years, solar cells (solar cells) using photoelectric conversion elements are expected to be widely used, not only from the perspective of fossil fuel conservation and global warming mitigation, but also as self-supporting power sources that require neither cell replacement nor power source wiring. Furthermore, solar cells as self-supporting power sources are attracting significant attention as one of the energy harvesting technologies required for Internet of Things (IoT) devices and artificial satellites.

[0003] The strengths of solar cells include organic solar cells such as dye-sensitized solar cells, organic film solar cells, and perovskite solar cells, as well as inorganic solar cells using silicon, which have been widely used. From the perspective of improving safety and suppressing production costs, perovskite solar cells are advantageous because they can be produced using conventional existing printing cells without using electrolyte-containing solvents such as organic solvents.

[0004] With respect to organic film solar cells and perovskite solar cells, it is known that a plurality of spatially separated photoelectric conversion elements are electrically connected to form a series circuit to increase output voltage (see, for example, PTL 1).

[0005] Citation List

[0006] Patent Literature

[0007] PTL1: Japanese Unexamined Patent Application Publication No. 2016-195175 Summary of the Invention

[0008] Technical issues

[0009] An object of the present disclosure is to provide a photoelectric conversion element that can maintain power generation efficiency even after being exposed to light of high illuminance for a long period of time.

[0010] Solution to the problem

[0011] According to one aspect of the present disclosure, a photoelectric conversion element includes: a first carrier; a first electrode; an electron transport layer; a photoelectric conversion layer; a hole transport layer; and a second electrode.

[0012] The hole transport layer includes a polymer including a repeating unit represented by the following general formula (1), and a compound represented by the following general formula (2).

[0013]

[0014] In the general formula (1), Ar1 represents an aromatic hydrocarbon group, and the aromatic hydrocarbon group may be substituted by a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group, which may be substituted by a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted by a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group, or an aryl group; and n represents an integer of 2 or greater and allowing the polymer represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater.

[0015]

[0016] In the general formula (2), R5 to R9 may be the same as or different from each other and represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group; and X represents a cation.

[0017] Advantageous Effects of the Invention

[0018] According to the present disclosure, it is possible to provide a photoelectric conversion element that can maintain power generation efficiency even after being exposed to light of high illuminance for a long period of time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] [ Figure 1 ] Figure 1 is a schematic view of an example of a solar battery cell as one embodiment of a photoelectric conversion element.

[0020] [ Figure 2 ] Figure 2 is a block diagram of a mouse of a personal computer as an example of the electronic device of the present disclosure.

[0021] [ Figure 3 ] Figure 3 Yes Figure 2 Schematic external view of one example of a mouse presented in .

[0022] [ Figure 4 ] Figure 4 is a block diagram of a keyboard of a personal computer as one example of the electronic device of the present disclosure.

[0023] [ Figure 5 ] Figure 5 Yes Figure 4 Schematic external view of an example of a keyboard presented in .

[0024] [ Figure 6 ] Figure 6 Yes Figure 4 A schematic external view of another example of a keyboard is presented in FIG.

[0025] [ Figure 7 ] Figure 7 is a block diagram of a sensor as one example of an electronic device of the present disclosure.

[0026] [ Figure 8 ] Figure 8 is a block diagram of a turntable as one example of the electronic device of the present disclosure.

[0027] [ Figure 9 ] Figure 9 is a block diagram of one example of an electronic device that presents the present disclosure.

[0028] [ Figure 10 ] Figure 10 is a block diagram of an example in which a power supply integrated circuit (IC) is further incorporated into Figure 9 In the electronic device presented in.

[0029] [ Figure 11 ] Figure 11 A block diagram of an example in which an electricity storage device is further incorporated into Figure 10 In the electronic device presented in.

[0030] [ Figure 12 ] Figure 12 is a block diagram showing one example of a power supply module of the present disclosure.

[0031] [ Figure 13 ] Figure 13 is a block diagram showing an example in which the power storage device is further incorporated into Figure 12 The power module is shown in Figure 2. DETAILED DESCRIPTION

[0032] (Photoelectric conversion element)

[0033] The photoelectric conversion element means an element that can convert light energy into electric energy or convert electric energy into light energy, and is applied to, for example, a solar cell and a photodiode.

[0034] The photoelectric conversion element of the present disclosure includes at least a first support, a first electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, and a second electrode, and further includes other components if necessary.

[0035] <First Electrode>

[0036] The shape and size of the first electrode are not particularly limited and may be appropriately selected depending on the intended purpose.

[0037] The structure of the first electrode is not particularly limited and may be appropriately selected depending on the intended purpose.The structure of the first electrode may be a single layer structure, or a structure in which a plurality of layers are stacked.

[0038] The material of the first electrode is not particularly limited and may be appropriately selected depending on the intended purpose, as long as the material has conductivity. Examples of the material include transparent conductive metal oxides, carbon, and metals.

[0039] Examples of transparent conductive metal oxides include indium tin oxide (hereinafter referred to as "ITO"), fluorine-doped tin oxide (hereinafter referred to as "FTO"), antimony-doped tin oxide (hereinafter referred to as "ATO"), niobium-doped tin oxide (hereinafter referred to as "NTO"), aluminum-doped zinc oxide (hereinafter referred to as "AZO"), zinc oxide-indium, and titanium oxide-niobium.

[0040] Examples of carbon include carbon black, carbon nanotubes, graphene, and fullerene.

[0041] Examples of metals include gold, silver, aluminum, nickel, indium, tantalum, and titanium.

[0042] These may be used alone or in combination. Among them, preferred are transparent conductive metal oxides having high transparency, and more preferred are ITO, FTO, ATO, NTO, and AZO.

[0043] The average thickness of the first electrode is not particularly limited and can be appropriately selected depending on the intended purpose. The average thickness of the first electrode is preferably 5 nm or more but 100 microns or less, more preferably 50 nm or more but 10 microns or less. When the first electrode is carbon or metal, the average thickness of the first electrode is preferably an average thickness sufficient to achieve translucency.

[0044] The first electrode can be formed by a known method such as a sputtering method, an evaporation method, and a spray method.

[0045] Furthermore, the first electrode is preferably formed on a substrate. An integrated commercially available product in which the first electrode is previously formed on a substrate may be used.

[0046] Examples of commercially available products that have been integrated include: FTO-coated glass, ITO-coated glass, zinc oxide / aluminum-coated glass, FTO-coated transparent plastic films, and ITO-coated transparent plastic films. Other examples of commercially available products that have been integrated include: a glass substrate provided with a transparent electrode in which tin oxide or indium oxide is doped with cations or anions having different atomic valences; and a glass substrate provided with a metal electrode having a structure that allows light to pass through in the form of a mesh or stripes.

[0047] These may be used alone, or two or more products may be used in combination as a mixture or laminate. In addition, metal wires may be used in combination in order to reduce resistance values.

[0048] In order to produce a photoelectric conversion module to be described below, the electrodes of the integrated commercially available products may be appropriately processed to produce a substrate on which a plurality of first electrodes are formed.

[0049] Materials of the metal wires are, for example, aluminum, copper, silver, gold, platinum, and nickel.

[0050] The metal wires can be used in combination by forming the metal wires on a substrate by, for example, evaporation, sputtering, or pressure bonding and disposing a layer of ITO or FTO thereon, or by forming the metal wires on ITO or FTO.

[0051] <Electron Transport Layer>

[0052] The electron transport layer is a layer that transports electrons generated in the photoelectric conversion layer to the first electrode. The photoelectric conversion layer will be described below. Therefore, the electron transport layer is preferably arranged adjacent to the first electrode.

[0053] The shape and size of the electron transport layer are not particularly limited and may be appropriately selected depending on the intended purpose.

[0054] The structure of the electron transport layer may be a single layer or may be a multilayer in which a plurality of layers are stacked.

[0055] The electron transport layer includes an electron transport material.

[0056] The electron transport material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the electron transport material include semiconductor materials.

[0057] The semiconductor material is not particularly limited, and known materials can be used.

[0058] Examples of semiconductor materials include simple semiconductors and compounds of compound semiconductors.

[0059] Examples of elemental semiconductors include silicon and germanium.

[0060] Examples of compound semiconductors include metal chalcogenides.

[0061] Examples of metal chalcogenides include metal oxides (oxide semiconductors), metal sulfides, metal selenides, and metal tellurides.

[0062] Examples of the metal oxide (oxide semiconductor) include oxides of titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, and tantalum.

[0063] Examples of the metal sulfides include sulfides of cadmium, zinc, lead, silver, antimony, and bismuth.

[0064] Examples of metal selenides include selenides of cadmium and lead.

[0065] Examples of the metal telluride include cadmium telluride.

[0066] Other examples of compound semiconductors include: zinc, gallium, indium, and cadmium phosphides; gallium arsenide; indium-copper selenide; and indium-copper sulfide.

[0067] Among them, metal oxides (oxide semiconductors) are preferred. In particular, it is preferred to include at least one selected from titanium oxide, zinc oxide, tin oxide, and niobium oxide. It is particularly preferred to include tin oxide.

[0068] These may be used alone or in combination. In addition, the crystal form of the semiconductor material is not particularly limited and may be appropriately selected depending on the intended purpose. Its crystal form may be single crystal, polycrystalline or amorphous.

[0069] The electron transport layer includes at least one compound selected from the following on the electron transport material on the surface of the electron transport layer on one side of the photoelectric conversion layer: a phosphonic acid compound, a boric acid compound, a sulfonic acid compound, a halosilyl compound, and an alkoxysilyl compound. When the electron transport layer includes the aforementioned compounds on the surface of the electron transport material on one side of the photoelectric conversion layer, it is expected that the physical properties of the boundary between the electron transport layer and the photoelectric conversion layer can be controlled. In other words, when the electron transport material is covered with these compounds on the surface of the electron transport layer on one side of the photoelectric conversion layer, it is expected that the boundary resistance between the electron transport layer and the photoelectric conversion layer is reduced to make the electron transfer smooth.

[0070] These compounds may be bonded to the electron transport material. Examples of bonds include covalent bonds and ionic bonds.

[0071] The compound is at least one selected from the group consisting of a phosphonic acid compound, a boric acid compound, a sulfonic acid compound, a halogenated silyl compound, and an alkoxysilyl compound.

[0072] From the viewpoint of compatibility with the perovskite layer, the compound preferably includes a nitrogen atom.

[0073] The phosphonic acid compound is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it includes a phosphonic acid group. Specific examples of the phosphonic acid compound will be described later.

[0074] The boronic acid compound is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it includes a boronic acid group. Specific examples of the boronic acid compound will be described later.

[0075] The sulfonic acid compound is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it includes a sulfonic acid group. Specific examples of the sulfonic acid compound will be described later.

[0076] The halosilyl compound is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it includes a halosilyl group. Specific examples of the halosilyl compound will be described later.

[0077] The alkoxysilyl compound is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it includes an alkoxysilyl group. Specific examples of the alkoxysilyl compound will be described later.

[0078] The molecular weight of the compound is not particularly limited and may be appropriately selected depending on the intended purpose. The molecular weight of the compound is, for example, 100 or more but 500 or less.

[0079] The compound is represented by, for example, the following general formula (3).

[0080]

[0081] In the general formula (3), R1 and R2 may be the same as or different from each other, represent a hydrogen atom, an alkyl group, an aryl group, or a heterocycle, R3 represents a divalent alkylene group, a divalent aryl group, or a divalent heterocycle, R4 represents a phosphonic acid group, a boronic acid group, a sulfonic acid group, a halosilyl group, or an alkoxysilyl group, and R1 or R2, R3, and N may be connected together to form a ring structure.

[0082] Examples of the compound include the following compounds.

[0083]

[0084]

[0085] The thickness of the electron transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. The thickness of the electron transport layer is preferably, for example, 5 nm or more but 1 micrometer or less, more preferably 10 nm or more but 700 nm or less.

[0086] Preferably, the surface of the electron transport layer on one side of the photoelectric conversion layer is as smooth as possible. Preferably, the roughness factor (roughness factor) as an indicator of smoothness is small. However, from the perspective of the relationship with the average thickness of the electron transport layer, the roughness factor of the electron transport layer on one side of the photoelectric conversion layer is preferably 20 or less, more preferably 10 or less. The lower limit of the roughness factor is not particularly limited and can be appropriately selected depending on the intended purpose. Therefore, its lower limit is, for example, 1 or greater.

[0087] The roughness factor is the ratio of the actual surface area to the apparent surface area and is also known as the Wenzel roughness factor. The actual surface area can be determined, for example, by measuring the BET specific surface area. This value can be divided by the apparent surface area to obtain the roughness factor.

[0088] The method for producing a film of the electron transport material in the electron transport layer is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include: a method in which a film of the electron transport material is formed in a vacuum (vacuum film forming method); and a wet film forming method.

[0089] Vacuum film forming methods include sputtering, pulsed laser deposition (PLD), ion beam sputtering, ion-assisted deposition, ion plating, vacuum deposition, atomic layer deposition (ALD), and chemical vapor deposition (CVD).

[0090] Examples of wet film-forming methods include sol-gel methods. The sol-gel method is the following method. Specifically, a solution is allowed to undergo a chemical reaction (such as polymerization condensation) to prepare a gel. It is then subjected to heat treatment to promote compactness. When using the sol-gel method, the method for applying the sol solution is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include dipping, spraying, wire bar method, spin coating, roller coating, blade coating, gravure coating, wet printing, such as relief printing, offset printing, gravure printing, intaglio printing, rubber plate printing, and screen printing. The temperature for heat treatment after sol solution coating is preferably 80°C or higher, more preferably 100°C or higher.

[0091] The method for providing the compound on the electron transport material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the method include a method in which a solution containing the compound is applied to a film of the electron transport material, followed by drying.

[0092] The coating method is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the coating method include dipping, spraying, wire bar coating, spin coating, roll coating, blade coating, and gravure coating.

[0093] The temperature of the drying treatment performed after coating the solution is preferably 40° C. or higher, more preferably 50° C. or higher.

[0094] <Photoelectric Conversion Layer>

[0095] The photoelectric conversion layer is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it is a layer that performs photoelectric conversion.

[0096] Examples of the photoelectric conversion layer include a perovskite layer and a bulk heterojunction layer.

[0097] <<Perovskite layer>>

[0098] The perovskite layer means a layer containing a perovskite compound and absorbing light to sensitize the electron transport layer. Therefore, the perovskite layer is preferably arranged adjacent to the electron transport layer.

[0099] The shape and size of the perovskite layer are not particularly limited and may be appropriately selected depending on the intended purpose.

[0100] The perovskite compound is a complex substance of an organic compound and an inorganic compound, and is represented by the following general formula (4).

[0101] X α Y β Z γ ···General formula (4)

[0102] In general formula (4), the ratio of α:β:γ is 3:1:1; β and γ are each an integer greater than 1; X represents a halogen atom; Y represents an organic compound including an amino group; and Z represents a metal ion.

[0103] X in the general formula (4) is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include halogen atoms such as chlorine, bromine, and iodine. These can be used alone or in combination.

[0104] Examples of Y in the above general formula (4) include organic cations such as ions of alkylamine compounds (e.g., methylamine, ethylamine, n-butylamine, and formamidine); and inorganic alkali metal cations (e.g., Sb atom, Cs atom, Rb atom, and K atom). These can be used alone or in combination. The inorganic alkali metal cations and the organic cations can each be used in combination. Among them, organic compounds containing an amino group are preferred.

[0105] In the case of a perovskite compound of lead halide and methylammonium, the peak λmax of the optical absorption spectrum is as follows: when the halogen ion is Cl, it is approximately 350 nm; when the halogen ion is Cr, it is approximately 410 nm; and when the halogen ion is I, it is approximately 540 nm. As described above, the peak λmax shifts toward longer wavelengths, and thus the available spectral width (bandwidth) changes.

[0106] Z in the above general formula (4) is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include ions of metals such as lead, indium, antimony, tin, copper, and bismuth. These can be used alone or in combination.

[0107] Preferably, the perovskite layer has a stacked perovskite structure in which layers formed of metal halide and layers of aligned organic cation molecules are alternately stacked.

[0108] The method for forming the perovskite layer is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include a method in which a solution obtained by dissolving or dispersing, for example, a metal halide and a halogenated alkylamine or a cesium halide is applied and then dried.

[0109] Examples of methods for forming a perovskite layer include a two-step precipitation method as described below. Specifically, a solution obtained by dissolving or dispersing a metal halide is applied and then dried. The resulting solution is then immersed in a solution obtained by dissolving a halogenated alkylamine to form a perovskite compound.

[0110] In addition, an example of a method for forming a perovskite layer includes a method in which a poor solvent (a solvent with low solubility) of a perovskite compound is added thereto while simultaneously applying a solution obtained by dissolving or dispersing, for example, a metal halide and a halogenated alkylamine thereon to precipitate crystals. In addition, an example of a method for forming a perovskite layer includes a method for depositing a metal halide in a gas filled with, for example, methylamine.

[0111] Among them, preferred is a method of adding a poor solvent for the perovskite compound therein while applying a solution obtained by dissolving or dispersing, for example, a metal halide and a halogenated alkylamine thereon to precipitate crystals.

[0112] The method for applying the solution is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include immersion, spin coating, spray coating, dipping, roller coating, and air knife coating. As a method for applying the solution, a method of precipitation using carbon dioxide in a supercritical fluid can be used.

[0113] Furthermore, the perovskite layer may include a sensitizing dye.

[0114] The method for forming a perovskite layer including a sensitizing dye is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include a method in which a perovskite compound and a sensitizing dye are mixed, and a method in which a perovskite layer is formed and then the sensitizing dye is absorbed.

[0115] The sensitizing dye is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it is a compound that is photoexcited by excitation light to be used.

[0116] Examples of the sensitizing dye include metal complex compounds, coumarin compounds, polyene compounds, indoline compounds, thiophene compounds, cyanine dyes, merocyanine dyes, 9-arylxanthene compounds, triarylmethane compounds, phthalocyanine compounds, and porphyrin compounds.

[0117] Examples of the metal complex compound include metal complex compounds described in, for example, Japanese Translation of PCT International Application Publication No. 7-500630, Japanese Unexamined Patent Application Publication No. 10-233238, Japanese Unexamined Patent Application Publication No. 2000-26487, Japanese Unexamined Patent Application Publication No. 2000-323191, and Japanese Unexamined Patent Application Publication No. 2001-59062.

[0118] Examples of the coumarin compound include coumarin compounds described in, for example, Japanese Unexamined Patent Application Publication No. 10-93118, Japanese Unexamined Patent Application Publication No. 2002-164089, Japanese Unexamined Patent Application Publication No. 2004-95450, and J. Phys. Chem. C, 7224, Vol. 111 (2007).

[0119] Examples of the polyene compound include polyene compounds described in, for example, Japanese Unexamined Patent Application Publication No. 2004-95450, and Chem. Commun., 4887 (2007).

[0120] Examples of the indoline compounds include indoline compounds described in, for example, Japanese Unexamined Patent Application Publication No. 2003-264010, Japanese Unexamined Patent Application Publication No. 2004-63274, Japanese Unexamined Patent Application Publication No. 2004-115636, Japanese Unexamined Patent Application Publication No. 2004-200068, Japanese Unexamined Patent Application Publication No. 2004-235052, J. Am. Chem. Soc., 12218, Vol. 126 (2004), Chem. Commun., 3036 (2003), and Angew. Chem. Int. Ed., 1923, Vol. 47 (2008).

[0121] Examples of the thiophene compound include thiophene compounds described in, for example, J. Am. Chem. Soc., 16701, Vol. 128 (2006), and J. Am. Chem. Soc., 14256, Vol. 128 (2006).

[0122] Examples of the anthocyanin dye include anthocyanin dyes described in, for example, Japanese Unexamined Patent Application Publication No. 11-86916, Japanese Unexamined Patent Application Publication No. 11-214730, Japanese Unexamined Patent Application Publication No. 2000-106224, Japanese Unexamined Patent Application Publication No. 2001-76773, and Japanese Unexamined Patent Application Publication No. 2003-7359.

[0123] Examples of the merocyanine dye include those described in, for example, Japanese Unexamined Patent Application Publication No. 11-214731, Japanese Unexamined Patent Application Publication No. 11-238905, Japanese Unexamined Patent Application Publication No. 2001-52766, Japanese Unexamined Patent Application Publication No. 2001-76775, and Japanese Unexamined Patent Application Publication No. 2003-7360.

[0124] Examples of the 9-arylxanthene compound include 9-arylxanthene compounds described in, for example, Japanese Unexamined Patent Application Publication No. 10-92477, Japanese Unexamined Patent Application Publication No. 11-273754, Japanese Unexamined Patent Application Publication No. 11-273755, and Japanese Unexamined Patent Application Publication No. 2003-31273.

[0125] Examples of the triarylmethane compound include triarylmethane compounds described in, for example, Japanese Unexamined Patent Application Publication No. 10-93118 and Japanese Unexamined Patent Application Publication No. 2003-31273.

[0126] Examples of the phthalocyanine compounds and porphyrin compounds include phthalocyanine compounds and porphyrin compounds described in, for example, Japanese Unexamined Patent Application Publication No. 9-199744, Japanese Unexamined Patent Application Publication No. 10-233238, Japanese Unexamined Patent Application Publication No. 11-204821, Japanese Unexamined Patent Application Publication No. 11-265738, J. Phys. Chem., 2342, Vol. 91 (1987), J. Phys. Chem. B, 6272, Vol. 97 (1993), Electroanal. Chem., 31, Vol. 537 (2002), Japanese Unexamined Patent Application Publication No. 2006-032260, J. Porphyrins Phthalocyanines, 230, Vol. 3 (1999), Angew. Chem. Int. Ed., 373, Vol. 46 (2007), and Langmuir, 5436, Vol. 24 (2008).

[0127] Among them, preferred are metal complex compounds, indoline compounds, thiophene compounds, and porphyrin compounds.

[0128] <<Bulk Heterojunction Layer>>

[0129] The bulk heterojunction layer includes an electron-donating organic material and an electron-withdrawing organic material.

[0130] In a bulk heterojunction layer, an electron-donating organic material (P-type organic semiconductor) and an electron-withdrawing organic material (N-type organic semiconductor) are mixed to form a bulk heterojunction, a nanometer-sized PN junction. As a result, photoinduced charge separation at the junction surface can be used to generate current.

[0131] <<<Electron Donating Organic Materials (P-Type Organic Semiconductors)>>>

[0132] Examples of P-type organic semiconductors include conjugated polymers and low molecular weight compounds such as polythiophene or its derivatives, arylamine derivatives, stilbene derivatives, oligothiophene or its derivatives, phthalocyanine derivatives, porphyrin or its derivatives, polyphenylene vinylene or its derivatives, polythienylene vinylene or its derivatives, benzodithiophene derivatives, and diketo-pyrrolo-pyrrole derivatives. These can be used alone or in combination.

[0133] Among them, polythiophene or its derivatives as π-conjugated conductive polymers are preferred. Polythiophene and its derivatives are advantageous because they can ensure excellent stereoregularity and have relatively high solubility in solvents.

[0134] The polythiophene and its derivatives are not particularly limited and may be appropriately selected depending on the intended purpose, as long as they have a thiophene skeleton.

[0135] Examples thereof include polyalkylthiophenes such as poly-3-hexylthiophene; polyalkylisobenzothiophenes such as poly-3-hexylisobenzothiophene, poly-3-octylisobenzothiophene, and poly-3-decylisobenzothiophene; and polyethylenedioxythiophene.

[0136] In recent years, derivatives of copolymers including benzodithiophene, carbazole, benzothiadiazole, and thiophene have been exemplified as compounds that can achieve excellent photoelectric conversion efficiency, such as PTB7 (poly[{4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}]) and PCDTBT (poly[N-9′′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole])).

[0137] In addition to conjugated polymers, compounds that can achieve excellent photoelectric conversion efficiency even among low-molecular-weight compounds obtained by combining an electron-donating unit with an electron-withdrawing unit are already known and can also be used in the present disclosure (see, for example, ACS Appl. Mater. Interfaces 2014, 6, 803-810).

[0138] Among the low-molecular-weight compounds as the electron-donating organic material, preferred are compounds represented by the following general formula (A).

[0139]

[0140] In the general formula (A), n represents an integer of 1 to 3.

[0141] R1 represents an n-butyl group, an n-hexyl group, an n-octyl group, an n-decyl group, or an n-dodecyl group.

[0142] R2 represents an oxygen atom having an alkyl group having 6 to 22 carbon atoms, a sulfur atom having an alkyl group having 6 to 22 carbon atoms, a carbon atom having an alkyl group having 6 to 22 carbon atoms, or a group represented by the following general formula (B). Among them, preferred are an oxygen atom having an alkyl group having 6 to 20 carbon atoms, a sulfur atom having an alkyl group having 6 to 20 carbon atoms, a carbon atom having an alkyl group having 6 to 20 carbon atoms, and a group represented by the following general formula (B).

[0143]

[0144] In the general formula (B), R3 and R4 represent a hydrogen atom or an alkyl group having 6 to 12 carbon atoms.

[0145] R5 represents an alkyl group including 6 to 22 carbon atoms and which may be branched. Among them, an alkyl group including 6 to 12 carbon atoms and which may be branched is preferred.

[0146] As the electron donating organic material, examples of the low molecular weight compound are preferably compounds represented by the following general formula (C).

[0147]

[0148] In the general formula (C), R3 and R4 represent a hydrogen atom or an alkyl group having 6 to 12 carbon atoms, and preferably represent a hydrogen atom or an alkyl group having 6 to 10 carbon atoms.

[0149] R5 represents an alkyl group having 6 to 22 carbon atoms and which may be branched, and preferably represents an alkyl group having 6 to 12 carbon atoms and which may be branched.

[0150] Specific examples of the compound represented by general formula (C) will be described below. However, the present disclosure is not limited thereto.

[0151] [Table 1]

[0152] Example compounds <![CDATA[R3]]> <![CDATA[R4]]> <![CDATA[R5]]> 1 H H 2-Ethylhexyl 2 H n-Hexyl n-Hexyl 3 H H n-Hexyl 4 n-Hexyl H n-Hexyl 5 H H 2-Butyloctyl 6 H n-octyl n-octyl 7 H H n-octyl 8 n-octyl H n-octyl 9 H H 2-Decyldodecyl 10 H n-Dodecyl n-Dodecyl 11 H H n-Dodecyl 12 n-Dodecyl H n-Dodecyl

[0153] <<<Electron Withdrawing Organic Materials (N-Type Organic Semiconductors)>>>

[0154] Examples of electron-withdrawing organic materials include imide derivatives, fullerenes, and fullerene derivatives. Among them, fullerene derivatives are preferred from the viewpoint of charge separation and charge transport.

[0155] As the fullerene derivative, a properly synthesized product can be used, or a commercially available product can be used. Examples of fullerene derivatives include PC71BM (phenyl C71 butyric acid methyl ester, available from Frontier Carbon Corporation), PC61BM (phenyl C61 butyric acid methyl ester, available from Frontier Carbon Corporation), PC85BM (phenyl C85 butyric acid methyl ester, available from Frontier Carbon Corporation), and ICBA (fullerene indene 2 adduct, available from Frontier Carbon Corporation). In addition to the above, fulleropyrrolidine-based fullerene derivatives represented by general formula (D) can be used.

[0156]

[0157] In the general formula (D), Y1 and Y2 may be the same as or different from each other and represent a hydrogen atom, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, an alkynyl group which may have a substituent, an aryl group which may have a substituent, or an aralkyl group which may have a substituent.

[0158] Note that Y1 and Y2 are not hydrogen atoms at the same time.

[0159] Ar represents an aryl group which may have a substituent.

[0160] Specific examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, and a phenanthrenyl group. Among them, a phenyl group is preferred.

[0161] When Ar represents an aryl group having a substituent, the substituent preferably does not include an oxygen atom. Examples of the substituent include an aryl group, an alkyl group, a cyano group, an alkoxy group, and an alkoxycarbonyl group.

[0162] Among these substituents, examples of the aryl group include a phenyl group.

[0163] The alkyl group and the alkyl group portion of the alkoxy group are, for example, alkyl groups having 1 to 22 carbon atoms similar to the alkyl groups represented by Y1 and Y2 which will be described later.

[0164] The number and substitution sites of these substituents are not particularly limited. For example, 1 to 3 substituents may be present at any position of the aryl group represented by Ar.

[0165] Among the groups represented by Y1 and Y2, the alkyl group is preferably an alkyl group having 1 to 22 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, and particularly preferably an alkyl group having 6 to 12 carbon atoms. These alkyl groups may be linear or branched, but are particularly preferably linear.

[0166] The alkyl group may further include one or two or more hetero elements such as S and O in its carbon chain.

[0167] Among the groups represented by Y1 and Y2, the alkenyl group is preferably an alkenyl group having 2 to 10 carbon atoms. Particularly preferred specific examples thereof include linear or branched alkenyl groups having 2 to 4 carbon atoms, such as a vinyl group, a 1-propenyl group, an aryl group, an isopropenyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 1-methyl-2-propenyl group, and a 1,3-butadienyl group.

[0168] Among the groups represented by Y1 and Y2, the alkynyl group is preferably an alkynyl group having 1 to 10 carbon atoms. Particularly preferred specific examples thereof include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-methyl-2-propynyl group, a 1-butynyl group, a 2-butynyl group, and a 3-butynyl group.

[0169] Among the groups represented by Y1 and Y2, examples of the aryl group include a phenyl group, a naphthyl group, an anthracenyl group, and a phenanthrenyl group.

[0170] Among the groups represented by Y1 and Y2, examples of the aralkyl group include aralkyl groups having 7 to 20 carbon atoms, such as 2-phenylethyl, benzyl, 1-phenylethyl, 3-phenylpropyl, and 4-phenylbutyl.

[0171] As described above, the alkyl group, alkenyl group, alkynyl group, aryl group, and aralkyl group in the groups represented by Y1 and Y2 include the case where a substituent is included or the case where no substituent is included.

[0172] Substituents that may be included in the groups represented by Y1 and Y2 include: alkyl groups, alkoxycarbonyl groups, polyether groups, alkanoyl groups, amino groups, aminocarbonyl groups, alkoxy groups, alkylthio groups, the group: -CONHCOR' (wherein R' is an alkyl group), the group: -C(=NR')-R" (wherein R' and R" are alkyl groups), and the group: -NR'=CR"R"' (wherein R', R", and R"' are alkyl groups).

[0173] Among these substituents, examples of polyether groups include those represented by the formula Y3-(OY4) n Here, Y3 represents a monovalent hydrocarbon group such as an alkyl group, and Y4 represents a divalent aliphatic hydrocarbon group.

[0174] In the polyether group represented by the above formula, -(OY4) n Specific examples of the repeating unit represented by - include alkoxy chains such as -(OCH2) n -、-(OC2H4) n -, and -(OC3H6) n -. The repetition number n of these repeating units is preferably 1 to 20, more preferably 1 to 5. By -(OY4) n The repeating units represented by - may include not only the same repeating units but also two or more different repeating units. Among the aforementioned repeating units, -OC2H4- and -OC3H6- may have a straight chain or a linear chain.

[0175] Among the substituents, the alkyl group, and the alkyl group portion (R', R") in the alkoxycarbonyl group, the alkanoyl group, the alkoxy group, the alkylthio group, the polyether group, the group: -CONHCOR', the group: -C(=NR')-R", and the group: -NR'=CR"R"' is preferably an alkyl group having 1 to 22 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, and particularly preferably an alkyl group having 6 to 12 carbon atoms, similar to the aforementioned alkyl groups.

[0176] The amino group, and the amino group moiety in the aminocarbonyl group are particularly preferably an amino group to which one or more alkyl groups having 1 to 20 carbon atoms are bonded.

[0177] Among the fullerene derivatives represented by the general formula (D), examples of compounds having preferred properties include compounds represented by the general formula (D) wherein Ar represents a phenyl group which is a substituent or which does not have a substituent; and one of Y1 and Y2 is a hydrogen atom, and the other is an alkyl group which includes an alkoxycarbonyl group as a substituent, an alkyl group which includes an alkoxy group as a substituent, an alkyl group which includes a polyether group as a substituent, an alkyl group which includes an amino group as a substituent, or a phenyl group which includes a substituent or does not include a substituent.

[0178] Among these compounds, examples of compounds having particularly preferred properties include compounds represented by the general formula (D), wherein Ar includes a phenyl group, a cyano group, an alkoxy group, an alkoxycarbonyl group, or an alkyl group as a substituent, or represents a phenyl group not including a substituent; one of Y1 and Y2 is a hydrogen atom, and the other represents an alkyl group including an alkoxycarbonyl group as a substituent, an alkyl group including an alkoxy group as a substituent, an alkyl group including a polyether group as a substituent, a phenyl group, a phenyl group including an alkyl group as a substituent, a phenyl group including an alkoxycarbonyl group as a substituent, or a phenyl group including an alkoxy group as a substituent.

[0179] These compounds include groups with appropriate polarity on the pyrrolidine backbone and are excellent in self-assembly properties. Therefore, when forming a photoelectric conversion layer having a bulk heterojunction structure, a photoelectric conversion portion having a bulk heterojunction structure with an appropriate layer separation structure can be formed. As a result, for example, it is believed that electron mobility is improved to exhibit high conversion efficiency.

[0180] Examples of the most preferred compounds include compounds represented by the general formula (D), wherein Ar represents a phenyl group; one of Y1 and Y2 represents a hydrogen atom, and the other represents an unsubstituted alkyl group (an alkyl group having 4 to 6 carbon atoms), an unsubstituted phenyl group, a 1-naphthyl group, or a 2-naphthyl group.

[0181] The method for forming the bulk heterojunction layer is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include spin coating, blade coating, slit die coating, screen printing coating, bar coater coating, mold coating, transfer printing, dip drawing, inkjet, spray plating, and vacuum deposition. The coating method can be appropriately selected from these coating methods depending on the properties of the film of the organic material to be produced (e.g., thickness control and orientation control).

[0182] For example, when spin coating is performed, the P-type organic semiconductor and the N-type organic semiconductor preferably have a concentration of 5 mg / mL or higher but 40 mg / mL or lower. This concentration makes it easy to produce a uniform film of the organic material.

[0183] In order to remove the organic solvent from the film of the produced organic material, annealing treatment may be performed under reduced pressure or in an inert atmosphere (under a nitrogen or argon atmosphere). The temperature of the annealing treatment is preferably 40°C or higher but 300°C or lower, more preferably 50°C or higher but 200°C or lower. Annealing treatment can increase the effective area in which the deposited electrodes can penetrate and contact each other at the boundary. Therefore, the short-circuit current can be increased. Note that annealing treatment can be performed after electrode formation.

[0184] The organic solvent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the solvent include methanol, ethanol, butanol, toluene, xylene, o-chlorophenol, acetone, ethyl acetate, ethylene glycol, tetrahydrofuran, dichloromethane, chloroform, dichloroethane, chlorobenzene, dichlorobenzene, trichlorobenzene, chloronaphthalene, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, and gamma-butyrolactone. These can be used alone or in combination. Among them, preferred are chlorobenzene, chloroform, and o-dichlorobenzene.

[0185] In order to control the phase separation structure of the P-type organic semiconductor and the N-type organic semiconductor, an additive may be added to the organic solvent in an amount of 0.1% by mass or more but 10% by mass or less. Examples of the additive include iodoalkanes (e.g., 1,8-diiodooctane, 1,6-diiodohexane, and 1,10-diiododecane), alkanedithiols (e.g., 1,8-octanedithiol, 1,6-hexandithiol, and 1,10-decanedithiol), 1-chloronaphthalene, and polydimethylsiloxane derivatives.

[0186] The average thickness of the photoelectric conversion layer is preferably 50 nm or more but 400 nm or less, more preferably 60 nm or more but 250 nm or less. When the average thickness is 50 nm or more, insufficient carrier generation due to reduced light absorption in the photoelectric conversion layer does not occur. When the average thickness is 400 nm or less, the transport efficiency of carriers generated by light absorption does not further decrease.

[0187] <Organic Salts and Inorganic Salts>

[0188] The photoelectric conversion element preferably includes at least one salt selected from organic salts and inorganic salts between the photoelectric conversion layer and the hole transport layer.

[0189] When the photoelectric conversion element includes a salt between the photoelectric conversion layer and the hole transport layer, it can be expected that the physical properties of the boundary are controlled.

[0190] When the photoelectric conversion layer is a perovskite layer, the salt is preferably a salt different from a salt constituting the perovskite layer.

[0191] The salt is not particularly limited and may be appropriately selected depending on the intended purpose. In particular, when a perovskite compound is used in the photoelectric conversion layer, the cation preferably includes a halogen atom from the perspective of compatibility. Examples of the halogen atom include chlorine, iodine, and bromine.

[0192] In particular, when a perovskite compound is used in the photoelectric conversion layer, the organic salt is preferably a halogenated hydroacid salt of an amine from the viewpoint of compatibility.

[0193] In particular, when a perovskite compound is used in the photoelectric conversion layer, the inorganic salt is preferably a halide of an alkali metal from the viewpoint of compatibility.

[0194] Examples of alkali metals include lithium, sodium, potassium, rubidium, and cesium.

[0195] Examples of amine hydrohalides include n-butylamine hydrobromide, n-butylamine hydroiodide, n-hexylamine hydrobromide, n-hexylamine hydroiodide, n-decylamine hydrobromide, n-octadecylamine hydroiodide, pyridine hydrobromide, aniline hydroiodide, hydrazine dihydrobromide, ethylenediamine dihydroiodide, 2-phenylethylamine hydroiodide, phenylenediamine dihydrochloride, diphenylamine hydrobromide, diphenylamine hydroiodide, benzylamine hydroiodide, and 4-diphenylaminophenethylamine hydroiodide.

[0196] Examples of the alkali metal halide include cesium iodide, cesium bromide, rubidium iodide, and potassium iodide.

[0197] The method for providing at least one salt selected from organic salts and inorganic salts between the photoelectric conversion layer and the hole transport layer is not particularly limited and can be appropriately selected depending on the intended purpose. One example of such a method is a method in which a solution containing the salt is applied to the photoelectric conversion layer, then dried, and then a hole transport layer is formed thereon. Examples of the solution include aqueous solutions and alcoholic solutions.

[0198] The coating method is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the coating method include dipping, spraying, wire bar coating, spin coating, roll coating, blade coating, and gravure coating.

[0199] The temperature at the time of the drying treatment after coating the solution is not particularly limited and may be appropriately selected depending on the intended purpose.

[0200] It is not necessary to uniformly distribute the organic salt and the inorganic salt at the boundary between the perovskite layer and the hole transport layer. For example, the organic salt and the inorganic salt may be present in a localized manner (e.g., in the form of islands) at multiple regions. The perovskite compound of the perovskite layer may react with the hole transport material of the hole transport layer to distribute the organic salt and the inorganic salt in the perovskite layer or the hole transport layer. That is, such regions may include the organic salt and the inorganic salt present between the perovskite layer where neither the organic salt nor the inorganic salt is present and the hole transport layer where neither the organic salt nor the inorganic salt is present.

[0201] <Hole Transport Layer>

[0202] The hole transport layer is a layer that transports holes generated in the photoelectric conversion layer to a second electrode, which will be described below. Therefore, the hole transport layer is preferably disposed adjacent to the photoelectric conversion layer directly or via a salt.

[0203] The hole transport layer includes, for example, a solid hole transport material, and includes other materials if necessary.

[0204] The solid hole transport material (hereinafter may be simply referred to as "hole transport material") is not particularly limited and may be appropriately selected depending on the intended purpose as long as it is a material having properties such that holes can be transported. The hole transport layer is preferably an organic compound.

[0205] For example, when an organic compound is used as the hole transport material, the hole transport layer includes two or more compounds.

[0206] Examples of the organic compound include polymer materials.

[0207] The polymer material used in the hole transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polythiophene compounds, polystyrene vinylene compounds, polyfluorene compounds, polyphenylene compounds, polyarylamine compounds, and polythiadiazole compounds.

[0208] Examples of the polythiophene compound include poly(3-n-hexylthiophene), poly(3-n-octyloxythiophene), poly(9,9'-dioctyl-fluorene-co-bithiophene), poly(3,3"'-didodecanyl-quaterthiophene), poly(3,6-dioctylthieno[3,2-b]thiophene), poly(2,5-bis(3-decylthiophen-2-yl)thieno[3,2-b]thiophene), poly(3-decylthiophene-2-yl)thieno[3,2-b]thiophene, poly(3-decylthiophene-2-yl)thieno[3,2-b]thiophene), ... ), poly(3,4-didecylthieno[3,2-b]thiophene), poly(3,6-dioctylthieno[3,2-b]thiophene-co-thieno[3,2-b]thiophene), poly(3,6-dioctylthieno[3,2-b]thiophene-co-thiophene), and poly(3,6-dioctylthieno[3,2-b]thiophene-co-bithiophene)

[0209] Examples of the polystyrene vinylene compounds include poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylene vinylene], and poly[(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene)-co-(4,4′-biphenylene-vinylene)].

[0210] Examples of the polyfluorene compound include poly(9,9′-didodecylfluorenyl-2,7-diyl), poly[(9,9-dioctyl-2,7-divinylenefluorene)-alt-co-(9,10-anthracene)], poly[(9,9-dioctyl-2,7-divinylenefluorene)-alt-co-(4,4′-biphenylene)], poly[(9,9-dioctyl-2,7-divinylenefluorene)-alt-co-(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene)], and poly[(9,9-dioctyl-2,7-diyl)-co-(1,4-(2,5-dihexyloxy)benzene)].

[0211] Examples of the polyphenylene compound include poly[2,5-dioctyloxy-1,4-phenylene] and poly[2,5-di(2-ethylhexyloxy-1,4-phenylene].

[0212] Examples of the polyarylamine compound include poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(N,N'-diphenyl)-N,N'-di(p-hexylphenyl)-1,4-diaminobenzene], poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(N,N'-bis(4-octyloxyphenyl)benzidine-N,N'-(1,4-diphenylene)], poly[(N,N'-bis(4-octyloxyphenyl)benzidine-N,N'-(1,4-diphenylene)], poly [(N,N'-bis(4-(2-ethylhexyloxy)phenyl)benzidine-N,N'-(1,4-diphenylene)], poly[phenylimino-1,4-phenylenevinylene-2,5-dioctyloxy-1,4-phenylenevinylene-1,4-phenylene], poly[p-benzylimino-1,4-phenylenevinylene-2,5-di(2-ethylhexyloxy)-1,4-phenylenevinylene-1,4-phenylene], and poly[4-(2-ethylhexyloxy)phenylimino-1,4-biphenylene].

[0213] Examples of the polythiadiazole compound include poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(1,4-benzo(2,1′,3)thiadiazole], and poly(3,4-didecylthiophene-co-(1,4-benzo(2,1′,3)thiadiazole).

[0214] Among them, preferred are polythiophene compounds and polyarylamine compounds, and further preferred are polymers including a repeating unit represented by the following general formula (1), from the viewpoint of carrier mobility and ionization potential.

[0215] In the present disclosure, the hole transport layer includes a polymer including a repeating unit represented by the following general formula (1), and a compound represented by the following general formula (2). This makes it possible to reduce the resistance of the hole transport layer.

[0216]

[0217] In the general formula (1), Ar1 represents an aromatic hydrocarbon group, and the aromatic hydrocarbon group may be substituted by a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group, which may be substituted by a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted by a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group, or an aryl group; and n represents an integer of 2 or greater and allowing the polymer represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater.

[0218]

[0219] In the general formula (2), R5 to R9 may be the same as or different from each other and represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group; and X represents a cation.

[0220] Ar1 in the general formula (1) is an aromatic hydrocarbon group, and an example of the aromatic hydrocarbon group is, for example, an aryl group. Examples of aryl groups include: a phenyl group, a 1-naphthyl group, and a 9-anthryl group. The aryl group may have a substituent. Examples of substituents include: an alkyl group, an alkoxy group, and an aryl group.

[0221] Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group. Examples thereof include arylene groups and divalent heterocyclic groups. Examples of arylene groups include 1,4-phenylene, 1,1′-biphenylene, and 9,9′-di-n-hexylfluorene. Examples of divalent heterocyclic groups include 2,5-thiophene. The aryl group may have a substituent. Examples of substituents include: an alkyl group, an alkoxy group, and an aryl group.

[0222] Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, and an aryl group.

[0223] R1 to R4 each independently represent, for example, a hydrogen atom, an alkyl group, or an aryl group. Examples of alkyl groups include methyl groups and ethyl groups. Examples of aryl groups include phenyl groups and 2-naphthyl groups. The alkyl groups and aryl groups may have substituents.

[0224] The weight average molecular weight of the polymer including the repeating unit represented by the general formula (1) is preferably 2,000 or more but 100,000 or less.

[0225] The weight average molecular weight can be measured by gel permeation chromatography (GPC).

[0226] Specific examples of the polymer including the repeating unit represented by the general formula (1) include, but are not limited to, the following (A-01) to (A-20). In the formulae, n represents an integer of 2 or greater that allows the polymer including the repeating unit represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater.

[0227] Examples of the substituent at both terminals of each polymer include a hydrogen atom, an alkyl group, and an aryl group.

[0228]

[0229]

[0230] In general formula (2), R5 to R9 may be the same as or different from each other and represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group; X represents a cation; and R1 and R2 or R2 and R3 may be linked together to form a ring structure.

[0231] Examples of the halogen atom include a chlorine atom, a bromine atom, and an iodine atom.

[0232] Examples of the alkyl group include alkyl groups having 1 to 6 carbon atoms. The alkyl group may be substituted with a halogen atom.

[0233] Examples of the alkoxy group include alkoxy groups having 1 to 6 carbon atoms.

[0234] Examples of aryl groups include phenyl groups.

[0235] The cation is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of cations include alkali metal cations, phosphonium cations, iodonium cations, nitrogen-containing cations, and sulfonium cations. Nitrogen-containing cations refer to ions containing a positive charge on a nitrogen atom. Examples of nitrogen-containing cations include ammonium cations, pyridinium cations, and imidazolium cations.

[0236] Specific examples of the compound represented by the general formula (2) include, but are not limited to, the following (B-01) to (B-28).

[0237]

[0238]

[0239]

[0240]

[0241]

[0242] In the hole transport layer, the mass ratio (A:B) between the polymer A including the repeating unit represented by the general formula (1) and the compound B represented by the general formula (2) is not particularly limited and may be appropriately selected depending on the intended purpose. The mass ratio (A:B) is preferably 20:1 to 1:1, more preferably 10:1 to 1:1.

[0243] The hole transport layer may include a low molecular weight compound alone, or may include a mixture of a low molecular weight compound and a high molecular weight compound, in addition to the aforementioned polymer.

[0244] The chemical structure of the low-molecular hole transport material is not particularly limited. Examples thereof include oxadiazole compounds, triphenylmethane compounds, pyrazoline compounds, hydrazone compounds, tetraarylbenzidine compounds, stilbene compounds, spirobifluorene compounds, and thiophene oligomers.

[0245] Examples of the oxadiazole compound include oxadiazole compounds described in, for example, Japanese Examined Patent Publication No. 34-5466 and Japanese Unexamined Patent Application Publication No. 56-123544.

[0246] Examples of the triphenylmethane compound include triphenylmethane compounds described in, for example, Japanese Examined Patent Publication No. 45-555.

[0247] Examples of the pyrazoline compound include pyrazoline compounds described in, for example, Japanese Examined Patent Publication No. 52-4188.

[0248] Examples of the hydrazone compound include hydrazone compounds described in, for example, Japanese Examined Patent Publication No. 55-42380.

[0249] Examples of the tetraarylbenzidine compound include tetraarylbenzidine compounds described in, for example, Japanese Unexamined Patent Application Publication No. 54-58445.

[0250] Examples of the stilbene compounds include stilbene compounds described in, for example, Japanese Unexamined Patent Application Publication No. 58-65440 and Japanese Unexamined Patent Application Publication No. 60-98437.

[0251] Examples of the spirobifluorene compound include spirobifluorene compounds described in, for example, Japanese Unexamined Patent Application Publication No. 2007-115665, Japanese Unexamined Patent Application Publication No. 2014-72327, Japanese Unexamined Patent Application Publication No. 2001-257012, WO2004 / 063283, WO2011 / 030450, WO2011 / 45321, WO2013 / 042699, and WO2013 / 121835.

[0252] Examples of the thiophene oligomer include thiophene oligomers described in, for example, Japanese Unexamined Patent Application Publication No. 2-250881 and Japanese Unexamined Patent Application Publication No. 2013-033868.

[0253] When polymer and low molecular weight compound are mixed, the difference between each ionization potential is preferably 0.2eV or less. Ionization potential is the energy required to extract an electron from a molecule and is expressed in units of electron volts (eV). The method for measuring ionization potential is not particularly limited. However, ionization potential is preferably measured by photoelectron spectroscopy.

[0254] Other materials included in the hole transport layer are not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the other materials include additives and oxidizing agents.

[0255] The additive is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the additive include: iodine; metal iodides such as lithium iodide, sodium iodide, potassium iodide, cesium iodide, calcium iodide, copper iodide, iron iodide, and silver iodide; quaternary ammonium salts such as tetraalkylammonium iodides and pyridinium iodides; metal bromides such as lithium bromide, sodium bromide, potassium bromide, cesium bromide, and calcium bromide; bromide salts of quaternary ammonium compounds such as tetraalkylammonium bromides and pyridinium bromides; metal chlorides such as copper chloride and silver chloride; metal acetates such as Such as copper acetate, silver acetate, and palladium acetate; metal sulfates, such as copper sulfate and zinc sulfate; metal complexes, such as ferrocyanide-ferrocyanate and ferrocene-ferricinium; sulfur compounds, such as sodium polysulfide and alkylthiol-alkyl disulfide; viologen dyes; hydroquinone; and basic compounds, such as pyridine, 4-tert-butylpyridine, and benzimidazole.

[0256] An oxidizing agent may be further added. The type of oxidizing agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of oxidizing agents include tris (4-bromophenyl) aminium hexachloroantimonate, silver hexafluoroantimonate, nitrosium tetrafluoroborate, silver nitrate, cobalt complexes, and 4-isopropyl-4'-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate. Note that it is not necessary to use an oxidizing agent to oxidize the entire hole transport material, and it is effective as long as the hole transport material is partially oxidized. After the reaction, the oxidizing agent may or may not be removed from the system.

[0257] Including an oxidant in the hole transport layer can partially or completely form the hole transport material into radical cations, which makes it possible to improve conductivity and increase safety and durability of output characteristics.

[0258] The average thickness of the hole transport layer is not particularly limited and can be appropriately selected depending on the intended purpose. However, the average thickness thereof is preferably 0.01 μm or more but 20 μm or less, more preferably 0.1 μm or more but 10 μm or less, and still more preferably 0.2 μm or more but 2 μm or less on the photoelectric conversion layer.

[0259] The hole transport layer may be formed directly on the photoelectric conversion layer. The method for producing the hole transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the method include: a method in which a film is formed by vacuum deposition in a vacuum; and a wet film forming method. In particular, among them, from the perspective of production cost, the wet film forming method is preferred, and the method in which the hole transport layer is coated on the photoelectric conversion layer is more preferred.

[0260] The wet film forming method is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the wet film forming method include dipping, spraying, wire coating, spin coating, roller coating, blade coating, and gravure coating. As the wet printing method, methods such as letterpress printing, offset printing, gravure printing, gravure printing, rubber plate printing, and screen printing can be used.

[0261] In addition, the hole transport layer may be produced by forming a film in a supercritical fluid, or a subcritical fluid having a temperature and a pressure lower than a critical point.

[0262] A supercritical fluid is a fluid that exists as a non-condensable, high-density fluid in a temperature and pressure region exceeding a limit (critical point) at which gas and solid can coexist, does not condense even when compressed, and is a fluid in a state equal to or higher than a critical temperature and a critical pressure. The supercritical fluid is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably a supercritical fluid having a low critical temperature.

[0263] The subcritical fluid is not particularly limited and may be appropriately selected depending on the intended purpose as long as it is a fluid that exists as a high-pressure fluid in a temperature and pressure region near the critical point. The fluid exemplified as the supercritical fluid may be suitably used as the subcritical fluid.

[0264] Examples of the supercritical fluid include carbon monoxide, carbon dioxide, ammonia, nitrogen, water, alcohol solvents, hydrocarbon solvents, halogen solvents, and ether solvents.

[0265] Examples of the alcohol solvent include methanol, ethanol, and n-butanol.

[0266] Examples of hydrocarbon solvents include ethane, propane, 2,3-dimethylbutane, benzene, and toluene. Examples of halogen solvents include methylene chloride and chlorotrifluoromethane.

[0267] Examples of the ether solvent include dimethyl ether.

[0268] These may be used alone or in combination.

[0269] Among them, carbon dioxide (which has a critical pressure of 7.3 MPa and an adjacent temperature of 31° C.) is preferred because carbon dioxide easily produces a supercritical state, and it is non-flammable and easy to handle.

[0270] The critical temperature and critical pressure of the supercritical fluid are not particularly limited and may be appropriately selected depending on the intended purpose.The critical temperature of the supercritical fluid is preferably -273°C or higher but 300°C or lower, more preferably 0°C or higher but 200°C or lower.

[0271] In addition to the supercritical fluid and the subcritical fluid, an organic solvent or an entrainer may be used in combination. The solubility of the supercritical fluid can be easily adjusted by adding an organic solvent or an entrainer.

[0272] The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose.Examples of the organic solvent include ketone solvents, ester solvents, ether solvents, amide solvents, halogenated hydrocarbon solvents, and hydrocarbon solvents.

[0273] Examples of the ketone solvent include acetone, methyl ethyl ketone, and methyl isobutyl ketone.

[0274] Examples of ester solvents include ethyl formate, ethyl acetate, and n-butyl acetate.

[0275] Examples of the ether solvent include diisopropyl ether, dimethoxyethane, tetrahydrofuran, dioxolane, and dioxane.

[0276] Examples of the amide solvent include N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone.

[0277] Examples of the halogenated hydrocarbon solvent include dichloromethane, chloroform, bromoform, methyl iodide, dichloroethane, trichloroethane, trichloroethylene, chlorobenzene, o-dichlorobenzene, fluorobenzene, bromobenzene, iodobenzene, and 1-chloronaphthalene.

[0278] Examples of the hydrocarbon solvent include n-pentane, n-hexane, n-octane, 1,5-hexadiene, cyclohexane, methylcyclohexane, cyclohexadiene, benzene, toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and cumene.

[0279] These may be used alone or in combination.

[0280] After the hole transport material is deposited on the photoelectric conversion layer, a press process may be performed. By performing the press process, the hole transport material adheres more tightly to the photoelectric conversion layer, which may improve power generation efficiency in some cases.

[0281] The method of compression processing is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include: a press molding method using a plate, which can be represented by an infrared (IR) tablet molding device; and a roll press method using a roller.

[0282] The pressure of the pressing process is preferably 10 kgf / cm 2 or greater, more preferably 30 kgf / cm 2 or larger.

[0283] The pressing time is not particularly limited and can be appropriately selected depending on the intended purpose. The time is preferably 1 hour or less. In addition, heat can be applied during pressing.

[0284] During pressing, a release agent may be arranged between the pressing machine and the electrodes.

[0285] The release agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of release agents include fluorine-containing resins such as polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymers, perfluoroalkoxy fluoride resins, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymers, ethylene-chlorotrifluoroethylene copolymers, and polyvinyl fluoride. These can be used alone or in combination.

[0286] <Film Comprising Metal Oxide>

[0287] After pressing but before disposing the second electrode, a film including a metal oxide may be disposed between the hole transport layer and the second electrode.

[0288] The metal oxide is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of metal oxides include molybdenum oxide, tungsten oxide, vanadium oxide, and nickel oxide. These can be used alone or in combination. Among them, molybdenum oxide is preferred.

[0289] The method for disposing a film including a metal oxide on the hole transport layer is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include methods in which a film is formed in a vacuum, such as sputtering and vacuum evaporation; and wet film formation methods.

[0290] In the case where a film including a metal oxide is formed, a wet film-forming method is preferably a method in which a paste obtained by dispersing a powder or sol of the metal oxide is prepared and then coated on the hole transport layer.

[0291] The wet film forming method is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the wet film forming method include: dipping, spraying, wire coating, spin coating, roller coating, blade coating, and gravure coating. As the wet printing method, methods such as letterpress printing, offset printing, gravure printing, gravure printing, rubber plate printing, and screen printing can be used.

[0292] The average thickness of the film including the metal oxide is not particularly limited and may be appropriately selected depending on the intended purpose. However, the average thickness thereof is preferably 0.1 nm or more but 50 nm or less, more preferably 1 nm or more but 10 nm or less.

[0293] <Second Electrode>

[0294] The second electrode is preferably formed on the hole transport layer or the film including the metal oxide. The same as the first electrode can be used for the second electrode.

[0295] The shape, structure, and size of the second electrode are not particularly limited and may be appropriately selected depending on the intended purpose.

[0296] Examples of the material of the second electrode include metals, carbon compounds, conductive metal oxides, and conductive polymers.

[0297] Examples of metals include platinum, gold, silver, copper, and aluminum.

[0298] Examples of carbon compounds include graphite, fullerene, carbon nanotube, and graphene.

[0299] Examples of the conductive metal oxide include ITO, FTO, and ATO.

[0300] Examples of conductive polymers include polythiophene and polyaniline.

[0301] These may be used alone or in combination.

[0302] The second click may be appropriately formed on the hole transport layer by a method such as a coating method, a lamination method, a vacuum deposition method, a CVD method, or an adhesion method, depending on the kind of material to be used or the kind of the hole transport layer.

[0303] In a photoelectric conversion element, at least one of the first electrode and the second electrode is preferably substantially transparent. For example, the first electrode is preferably transparent to allow incident light to pass through one side of the first electrode. In this case, a light-reflecting material is preferably used for the second electrode, and glass, plastic, and metal films on which a metal or conductive oxide is deposited are preferably used. Furthermore, providing an antireflection layer on the side that receives incident light is an effective measure.

[0304] An example of the photoelectric conversion element will be described with reference to the drawings.

[0305] Figure 1 is a schematic view of an example of a solar cell as one embodiment of a photoelectric conversion element.

[0306] Figure 1 The solar cell unit cell 50 includes a first electrode 2 , a dense electron transport layer 3 , a perovskite layer 5 as a photoelectric conversion layer, a hole transport layer 6 , and a second electrode 7 .

[0307] The first electrode 2 is in contact with the dense electron transport layer 3 .

[0308] The dense electron transport layer 3 is in contact with the perovskite layer 5 .

[0309] The perovskite layer 5 is in contact with the hole transport layer 6 .

[0310] The hole transport layer 6 is in contact with the second electrode 7 .

[0311] (Photoelectric conversion module)

[0312] The photoelectric conversion module of the present disclosure includes a plurality of photoelectric conversion elements of the present disclosure electrically coupled in series or in parallel.

[0313] The photoelectric conversion module includes a plurality of photoelectric conversion elements of the present disclosure on a substrate, and preferably further includes a second substrate different from the substrate and a sealing component. If necessary, the photoelectric conversion module includes other components.

[0314] Examples of the photoelectric conversion module include a plurality of photoelectric conversion modules.

[0315] The photoelectric conversion module is a photoelectric conversion module in which a plurality of photoelectric conversion elements of the present disclosure are arranged on a substrate. In at least two photoelectric conversion elements adjacent to each other, the hole transport layer is continuous, and, in at least two photoelectric conversion elements adjacent to each other, the first electrode, the electron transport layer, and the photoelectric conversion layer are separated by the hole transport layer. Because the electron transport layer and the photoelectric conversion layer are separated, in such a photoelectric conversion module, the electron recombination caused by diffusion is reduced. Therefore, even after being exposed to a long period of time of high illumination light, the power generation efficiency can be maintained.

[0316] <Base Material>

[0317] The shape, structure, and size of the substrate are not particularly limited and may be appropriately selected depending on the intended purpose. Note that the above substrate may be referred to as a first substrate hereinafter.

[0318] The material of the first substrate preferably has translucency and insulating properties. Examples of such materials include glass, plastic films, and ceramics. Among these, in the case where a firing step for forming an electron transport layer is performed, a material having thermal resistance to the firing temperature is preferred. In addition, preferred examples of the first substrate include a flexible first substrate.

[0319] <Second Base Material>

[0320] The second substrate is arranged to face the first substrate so that the first substrate and the second substrate sandwich a plurality of photoelectric conversion elements of the present disclosure.

[0321] The shape, structure, and size of the substrate are not particularly limited and may be appropriately selected depending on the intended purpose.

[0322] The material of the second substrate is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the material include glass, plastic films, metal foils, and ceramics.

[0323] A convex-concave part may be formed at a connection portion between the second base material and the sealing member to increase adhesion, and the convex-concave part will be described below.

[0324] The formation method of the concavoconvex portion is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the formation method include a sandblasting method, a water jet method, a chemical etching method, a laser processing method, and a method using sandpaper.

[0325] The method for increasing the adhesion between the second substrate and the sealing component may be, for example, a method for removing organic matter on the surface of the second substrate, or a method for improving the hydrophilicity of the second substrate. The method for removing organic matter on the surface of the second substrate is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of such methods include UV ozone cleaning and oxygen plasma treatment.

[0326] <Sealing ingredients>

[0327] The sealing composition is disposed between the first base material and the second base material, and seals the photoelectric conversion element.

[0328] The material of the sealing component is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the material include cured products of acrylic resins and cured products of epoxy resins.

[0329] As the cured product of acrylic resin, any material known in the art may be used as long as the cured product of acrylic resin is a product obtained by curing a monomer or oligomer including an acryl group in its molecule.

[0330] As the cured product of the epoxy resin, any material known in the art may be used as long as the cured product of the epoxy resin is a product obtained by curing a monomer or oligomer including an epoxy group in its molecule.

[0331] Examples of epoxy resins include water-dispersible epoxy resins, non-solvent epoxy resins, solid epoxy resins, thermosetting epoxy resins, epoxy resins mixed with a curing agent, and ultraviolet-curable epoxy resins. Among these, thermosetting epoxy resins and ultraviolet-curable epoxy resins are preferred, and ultraviolet-curable epoxy resins are most preferred. Note that heating may be performed even when using an ultraviolet-curable epoxy resin, and preferably, heating is performed even after irradiation with ultraviolet radiation.

[0332] Examples of epoxy resins include bisphenol A-based epoxy resins, bisphenol F-based epoxy resins, novolac-based epoxy resins, alicyclic epoxy resins, long-chain aliphatic epoxy resins, glycidylamine-based epoxy resins, glycidylether-based epoxy resins, and glycidylester-based epoxy resins. These can be used alone or in combination.

[0333] If necessary, a curing agent or various additives are preferably mixed with the epoxy resin.

[0334] The curing agent is not particularly limited and may be appropriately selected depending on the intended purpose.The curing agent is classified into, for example, amine-based curing agents, acid anhydride-based curing agents, polyamide-based curing agents, and other curing agents.

[0335] Examples of the amine-based curing agent include aliphatic polyamines such as diethylenetriamine and triethylenetetramine; and aromatic polyamines such as methylphenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone.

[0336] Examples of the acid anhydride-based curing agent include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, pyromellitic anhydride, HET anhydride, and dodecenylsuccinic anhydride.

[0337] Examples of other curing agents include imidazoles and polythiols. These may be used alone or in combination.

[0338] The additive is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the additive include fillers, gap agents, polymerization initiators, desiccants (moisture absorbers), curing accelerators, coupling agents, softeners, colorants, flame retardant aids, antioxidants, and organic solvents. Among them, fillers, gap agents, curing accelerators, polymerization initiators, and desiccants (moisture absorbers) are preferred, and fillers and polymerization initiators are more preferred.

[0339] Including fillers as additives prevents the ingress of moisture and oxygen, and further achieves the following effects: reduced volume shrinkage during curing, reduced outgassing during curing or heating, improved mechanical strength, and control of thermal conductivity and fluidity. Therefore, including fillers as additives is quite effective in maintaining stable output under various environments.

[0340] Furthermore, from the perspective of the output properties and durability of photoelectric conversion elements, the effects of not only the passage of moisture and oxygen but also outgassing during curing or heating are not negligible. In particular, outgassing during heating significantly affects the output properties of photoelectric conversion elements stored in high-temperature environments.

[0341] The ingress of moisture or oxygen can be prevented by adding fillers, spacers, or desiccants to the sealing composition. Furthermore, when the amount of sealing composition used can be reduced, outgassing can be reduced. Including fillers, spacers, or desiccants in the sealing composition is effective not only during curing but also when the photoelectric conversion element is stored in a high-temperature environment.

[0342] The filler is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the filler include inorganic fillers such as crystalline or amorphous silica, talc, aluminum oxide, aluminum nitride, silicon nitride, calcium silicate, and calcium carbonate. These can be used alone or in combination.

[0343] The average primary particle size of the filler is preferably 0.1 μm or more but 10 μm or less, more preferably 1 μm or more but 5 μm or less. When the average primary particle size of the filler falls within the above preferred range, the effect of preventing the ingress of moisture or oxygen is fully achieved, the viscosity becomes appropriate, and the adhesion to the substrate or the defoaming property is improved. In addition, this is also effective in controlling the width of the seal portion or the workability.

[0344] The amount of the filler is preferably 10 parts by weight or more but 90 parts by weight or less, more preferably 20 parts by weight or more but 70 parts by weight or less, relative to the total amount of the sealing component (100 parts by weight). When the amount of the filler falls within the above preferred range, the effect of preventing the ingress of moisture or oxygen can be sufficiently obtained, the viscosity becomes appropriate, and the adhesion and workability are good.

[0345] A gap agent is also called a gap control agent or spacer. Including a gap agent as an additive allows the gap in the sealed portion to be controlled. For example, when a sealing composition is provided on a first substrate or a first electrode for sealing, and a second substrate is provided on the sealing composition, the gap in the sealed portion matches the size of the gap agent because the sealing composition includes the gap agent. As a result, the gap in the sealed portion can be easily controlled.

[0346] The spacer is not particularly limited and can be appropriately selected depending on the intended purpose, as long as it is particulate, has a uniform diameter, and has high solvent resistance and heat resistance. The spacer is preferably a material having a high affinity for epoxy resin and in the form of spherical particles. Preferred examples of the spacer include glass beads, silica fine particles, and organic resin fine particles. These can be used alone or in combination.

[0347] The length of the gap agent can be selected depending on the gap of the sealing portion to be set. The particle diameter thereof is preferably 1 micrometer or more but 100 micrometers or less, more preferably 5 micrometers or more but 50 micrometers or less.

[0348] The polymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose, as long as polymerization is initiated by heat or light. Examples of the polymerization initiator include thermal polymerization initiators and photopolymerization initiators.

[0349] Thermal polymerization initiators are compounds that generate active species such as free radicals and cations when heated. Examples of thermal polymerization initiators include azo compounds such as 2,2′-azobisbutyronitrile (AIBN) and peroxides such as benzoyl peroxide (BPO). Examples of thermal cationic polymerization initiators include benzenesulfonates and alkylsulfonium salts.

[0350] Meanwhile, photocationic polymerization initiators are preferably used in the case of epoxy resins as photopolymerization initiators. When the photocationic polymerization initiator is mixed with the epoxy resin and emits light, the photocationic polymerization initiator decomposes to produce acid, and this acid induces polymerization of the epoxy resin. Subsequently, the curing reaction proceeds. Photocationic polymerization initiators have the effects of reducing volume shrinkage caused during curing, preventing oxygen inhibition, and providing high storage stability.

[0351] Examples of the photocationic polymerization initiator include aromatic oxadiazolium salts, aromatic iodonium salts, aromatic sulfonium salts, metallocene compounds, and silanol-aluminum complexes.

[0352] In addition, a photoacid generator can also be used as a polymerization initiator. The photoacid generator has the function of generating acid when irradiated with light. The photoacid generator acts as an acid for initiating cationic polymerization. Examples of photoacid generators include onium salts, such as ionic onium salts based on sulfonium salts and ionic onium salts based on iodonium salts, which include a cationic portion and an ionic portion. These can be used alone or in combination.

[0353] The amount of the polymerization initiator added may vary depending on the material to be used. The amount of the polymerization initiator is preferably 0.5 parts by weight or more but 10 parts by weight or less, more preferably 1 part by weight or more but 5 parts by weight or less, relative to the total amount of the sealing component (100 parts by weight). When the amount of the polymerization initiator added falls within the aforementioned preferred range, curing proceeds appropriately, the remaining uncured product can be reduced, and excessive outgassing can be prevented.

[0354] Desiccant is also called moisture absorbent and is a material having the function of adsorbing or absorbing moisture physically or chemically. When the sealing component includes a desiccant, moisture resistance can be further improved and the effect of outgassing can be reduced.

[0355] The desiccant is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably a granular material. Examples of the desiccant include inorganic water-absorbing materials such as calcium oxide, barium oxide, magnesium oxide, magnesium sulfate, sodium sulfate, calcium sulfate, silica gel, molecular sieves, and zeolite. Among them, zeolite is preferred because it absorbs a large amount of water.

[0356] Curing accelerators are also called curing catalysts and are materials that speed up the curing process. Curing accelerators are mainly used for thermosetting epoxy resins.

[0357] The curing accelerator is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of curing accelerators include: tertiary amines or tertiary amine salts, such as DBU (1,8-diazabicyclo (5,4,0)-undecene-7) and DBN (1,5-diazabicyclo (4,3,0)-nonene-5); imidazole-based compounds, such as 1-cyanoethyl-2-ethyl-4-methylimidazole and 2-ethyl-4-methylimidazole; and phosphine or phosphonium salts, such as triphenylphosphine and tetraphenylphosphonium tetraphenylborate. These can be used alone or in combination.

[0358] The coupling agent is not particularly limited and may be appropriately selected depending on the intended purpose, as long as it is a material having an effect of increasing molecular bonding force. Examples of the coupling agent include silane coupling agents. Specific examples thereof include silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-(2-aminoethyl)3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)3-aminopropylmethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, N-(2-(vinylbenzylamino)ethyl)3-aminopropyltrimethoxysilane hydrochloride, and 3-methacryloxypropyltrimethoxysilane. These may be used alone or in combination.

[0359] As a sealing component, epoxy resin compositions commercially available as sealing materials, sealing materials, or adhesives are known, and such commercially available products can be effectively used in the present embodiment. Among them, there are also epoxy resin compositions developed and commercially available for use in solar cell batteries or organic EL elements, and such commercially available products can be particularly effectively used in the present embodiment. Examples of commercially available epoxy resin compositions include TB3118, TB3114, TB3124, and TB3125F (available from ThreeBond); World Rock 5910, World Rock 5920, and World Rock 8723 (available from Kyoritsu Chemical Co., Ltd.); and WB90US(P) (available from MORESCO Corporation).

[0360] As the sealing material, a sheet-type sealing material can be used.

[0361] Sheet-type sealing materials are materials in which an epoxy resin layer has been pre-formed on the sheet. Glass or film with high gas barrier properties is used in the sheet. The sheet-type sealing material can be bonded to a second substrate and then cured to form a sealing component and a second substrate at once. Depending on the formation pattern of the epoxy resin layer formed on the sheet, a structure with a hollow portion can be formed.

[0362] The method for forming the sealing composition is not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the method include: dispensing method, wire spindle method, spin coating method, roller coating method, blade coating method, and gravure coating method. In addition, as a method for forming the sealing composition, methods such as the following can be used: relief printing, offset printing, gravure printing, gravure printing, rubber plate printing, and screen printing.

[0363] In addition, a passivation layer may be disposed between the sealing component and the second electrode. The passivation layer is not particularly limited and may be appropriately selected depending on the intended purpose, as long as the passivation layer is disposed so that the sealing component does not contact the second electrode. Examples of the passivation layer include aluminum oxide, silicon nitride, and silicon oxide.

[0364] <Other ingredients>

[0365] Other ingredients are not particularly limited and may be appropriately selected depending on the intended purpose.

[0366] The photoelectric conversion module of the present disclosure can be applied to a power source device by being used in combination with, for example, a circuit board configured to control the generated current. Examples of devices using such a power source device include electronic calculators and watches. In addition, a power source device including the photoelectric conversion module of the present disclosure can be applied to, for example, mobile phones, electronic notepads, and electronic paper. A power source device including the photoelectric conversion module of the present disclosure can be used as an auxiliary power source configured to extend the continuous operating time of a rechargeable electrical appliance or a battery-type electrical appliance, or as a power source that can be used at night by being used in combination with a secondary battery. In addition, the photoelectric conversion module of the present disclosure can be used in IoT devices or artificial satellites as a self-supporting power source that does not require replacement of unit cells or power source wiring.

[0367] (Electronic equipment)

[0368] The electronic device of the present disclosure includes: the photoelectric conversion module of the present disclosure; and a device configured to be driven by power generated by photoelectric conversion of the photoelectric conversion module. If necessary, the electronic device of the present disclosure further includes other devices.

[0369] (Power Module)

[0370] The power module of the present disclosure includes: the photoelectric conversion module of the present disclosure; and a power integrated circuit (IC). If necessary, the power module of the present disclosure further includes other devices.

[0371] Specific embodiments of an electronic device including the photoelectric conversion module of the present disclosure and a device configured to be driven by electric power obtained by power generation of the photoelectric conversion module will be described.

[0372] Figure 2 is a block diagram of a mouse of a personal computer as an example of the electronic device of the present disclosure.

[0373] like Figure 2 As shown in [1], a photoelectric conversion module, a power supply IC, and a power storage device are combined, and the supplied power is allowed to flow to the power supply of the mouse control circuit. As a result, when the mouse is not in use, the power storage device is charged, allowing the mouse to be driven by electricity. This results in a mouse that requires neither wiring nor replacement of battery cells. This eliminates the need for battery cells, effectively reducing the weight of the mouse.

[0374] Figure 3 It is presented Figure 2 A schematic external view of one example of a mouse is shown in FIG.

[0375] like Figure 3 As shown in the figure, the photoelectric conversion module, power supply IC, and power storage device are installed inside the mouse, but the upper portion of the photoelectric conversion element is covered with a transparent housing, allowing the photoelectric conversion element of the photoelectric conversion module to receive light. Furthermore, the entire mouse housing can be formed from a transparent resin. The placement of the photoelectric conversion element is not limited to the above. For example, the photoelectric conversion element can be positioned so that it emits light even when the mouse is covered by a hand, and such a placement may be preferred.

[0376] Another embodiment of an electronic device including the photoelectric conversion module of the present disclosure and a device configured to be driven by electric power obtained by power generation of the photoelectric conversion module will be described.

[0377] Figure 4 is a block diagram of a keyboard of a personal computer as one example of the electronic device of the present disclosure.

[0378] like Figure 4 As shown in [1], a photoelectric conversion module, a power supply IC, and a power storage device are combined, and the supplied power is allowed to flow to the keyboard's control circuitry. As a result, when the keyboard is not in use, the power storage device is charged, allowing the keyboard to be powered by electricity. This results in a keyboard that requires neither wiring nor battery replacement. This configuration is effective because the mouse can be reduced in weight due to the lack of battery cells.

[0379] Figure 5 It is presented Figure 4 A schematic external view of one example of a keyboard is shown in FIG.

[0380] like Figure 5 As shown in , the photoelectric conversion element, power IC, and power storage device of the photoelectric conversion module are installed inside the keyboard, but the upper part of the photoelectric conversion element is covered with a transparent shell so that the photoelectric conversion element receives light. In addition, the shell of the entire keyboard can be formed of a transparent resin. The arrangement of the photoelectric conversion element is not limited to the above. In the case of a small keyboard (where the space for incorporating the photoelectric conversion element is small), the small photoelectric conversion element can be embedded in some keyboards, such as Figure 6 As shown in , such a setting is valid.

[0381] Next, another embodiment of an electronic device including the photoelectric conversion module of the present disclosure and a device configured to be driven by electric power obtained by power generation of the photoelectric conversion module will be described.

[0382] Figure 7 is a block diagram of a sensor as an example of an electronic device of the present disclosure.

[0383] like Figure 7 As shown in , the photoelectric conversion element, power IC, and power storage device in the photoelectric conversion module are combined, and the supplied power is allowed to go to the power supply of the sensor circuit. As a result, the sensor module can be constructed without the need to connect to an external power supply and without the need to replace the unit battery. The sensing target is, for example, temperature and humidity, illumination, human body detection, CO2, acceleration, UV, noise, geomagnetism, and atmospheric pressure, and such electronic equipment can be applied to various sensors, which is effective. Figure 7 As shown in , the sensor module is configured to periodically sense a target to be detected and transmit the read data to a personal computer (PC) or a smart phone via wireless communication.

[0384] It is expected that with the advent of the Internet of Things (IoT) society, the use of sensors will increase significantly. Replacing the batteries of numerous sensors one by one is time-consuming and impractical. In addition, the sensors are installed in locations where batteries cannot be easily replaced, such as ceilings and walls, and this arrangement makes workability poor. The implementation in which electricity can be supplied by photoelectric conversion elements is also significantly advantageous. In addition, the photoelectric conversion module of the present disclosure has the advantage of making it possible to obtain high output even with light of low illumination, and can achieve high installation freedom because the angle of incidence is less dependent on the angle of incidence of light.

[0385] Next, another embodiment of an electronic device including the photoelectric conversion module of the present disclosure and a device configured to be driven by electric power obtained by power generation of the photoelectric conversion module will be described.

[0386] Figure 8 is a block diagram of a turntable as one example of the electronic device of the present disclosure.

[0387] like Figure 8 As shown in , the electric conversion element, power IC, and power storage device are combined, and the supplied power is allowed to go to the power supply of the turntable control circuit. As a result, the turntable can be constructed without connecting to an external power supply and without replacing unit batteries.

[0388] The turntable can be used, for example, in a display case where products are displayed. Power wiring spoils the appearance of the display, and in addition, it is time-consuming to remove the displayed products when replacing the battery. Using the photoelectric conversion module of the present disclosure is effective because it can solve the aforementioned problems.

[0389] As described above, electronic devices and power supply modules have been described, including the photoelectric conversion module of the present disclosure and a device configured to be driven by the power generated by the photoelectric conversion module. However, the described embodiments are only a portion of applicable embodiments, and the uses of the photoelectric conversion module of the present disclosure are not limited to the above-described uses.

[0390] <Purpose>

[0391] The photoelectric conversion module of the present disclosure can act as a self-sustaining power source, and the electricity generated by photoelectric conversion can be used to drive the device. Because the photoelectric conversion module of the present disclosure can generate electricity by irradiation with light, it is not necessary to couple the electronic device to a power source or replace the unit battery. Therefore, the electronic device can be driven in a place where there is no power supply device, the electronic device can be worn or carried, and even in a place where the unit battery cannot be easily replaced, the electronic device can be driven without replacing the unit battery. In addition, when using dry unit batteries, the electronic device becomes heavier due to the weight of the dry unit batteries, or the electronic device becomes larger due to the size of the dry unit batteries. Therefore, there may be problems in installing the electronic device on a wall or ceiling, or transmitting the electronic device. However, because the photoelectric conversion module of the present disclosure is light and thin, it can be installed at will and can be worn and carried, which is advantageous.

[0392] As described above, the photoelectric conversion module of the present disclosure can be used as a self-sustaining power source and can be combined with various electronic devices. For example, the photoelectric conversion module of the present disclosure can be used in combination with the following: display devices (display devices) (e.g., electronic desktop calculators, watches, mobile phones, electronic organizers, and electronic paper), accessories of personal computers (e.g., mice and keyboards), various sensor devices (e.g., temperature and humidity sensors and human detection sensors), transmitters (e.g., beacons and global positioning systems (GPS)), and numerous electronic devices (e.g., auxiliary lights and remote controls).

[0393] The photoelectric conversion module of the present disclosure is widely used because it can generate electricity particularly by light of low illumination, and can generate electricity indoors and in further darker shades. In addition, the photoelectric conversion module is highly safe because liquid leakage, which is present in the case of dry cell batteries, does not occur, and accidental ingestion, which is present in the case of button cell batteries, does not occur. In addition, the photoelectric conversion module can be used as an auxiliary power source for the purpose of extending the continuous operation time of rechargeable or dry cell battery type electrical facilities. As described above, when the photoelectric conversion module of the present disclosure is combined with a device configured to be driven by electricity generated by photoelectric conversion of the photoelectric conversion module, an electronic device can be obtained that is light and easy to use, has a high degree of installation freedom, does not require replacement of cell batteries, excels in safety, and effectively reduces the environmental burden.

[0394] Figure 9 This diagram shows the basic configuration of an electronic device obtained by combining the photoelectric conversion module of the present disclosure with a device configured to be driven by power generated by photoelectric conversion by the photoelectric conversion module. When the photoelectric conversion element is illuminated by light, the electronic device can generate power and extract the power. The generated power can drive the device's circuitry.

[0395] Since the output of the photoelectric conversion element of the photoelectric conversion module varies depending on the circumferential illuminance, it may not be possible to stably drive the Figure 9 In this case, if Figure 10 As shown, a power supply IC for the photoelectric conversion element can be incorporated between the photoelectric conversion element and the device circuit in order to supply a stable voltage to the circuit side, and such an arrangement is effective.

[0396] The photoelectric conversion element of the photoelectric conversion module can generate electricity as long as it emits light with sufficient illumination. However, when the illumination is insufficient to generate electricity, the required power cannot be obtained, which is a disadvantage of the photoelectric conversion element. In this case, if Figure 11As shown in FIG, by installing a power storage device (such as a capacitor) between the power supply IC and the device circuit, excess power from the photoelectric conversion element can be stored in the power storage device. Furthermore, the power stored in the power storage device can be supplied to the device circuit, thereby enabling stable operation when the illumination is too low, or even when no light is applied to the photoelectric conversion element.

[0397] As described above, the electronic device obtained by combining the photoelectric conversion module of the present disclosure with a device circuit can be operated even in an environment without a power source, eliminating the need for battery replacement, and can be stably operated when combined with a power supply IC or power storage device. Therefore, the advantages of the photoelectric conversion element can be fully utilized.

[0398] At the same time, the photoelectric conversion module of the present disclosure can also be used as a power supply module, and such use is effective. Figure 12 As shown, for example, when the photoelectric conversion module of the present disclosure is coupled to a power supply IC of a photoelectric conversion element, a DC power supply module can be constructed, which can supply power generated by photoelectric conversion of the photoelectric conversion element of the photoelectric conversion module to the power supply IC at a predetermined voltage level.

[0399] In addition, if Figure 13 As shown in [1], by adding a power storage device to a power supply IC, the power generated by the photoelectric conversion elements of the photoelectric conversion module can be stored in the power storage device. This makes it possible to construct a power supply module that can supply power even when the illumination is too low, or even when no light is applied to the photoelectric conversion elements.

[0400] Figure 12 and Figure 13 The power module of the present disclosure shown in FIG. 1 can be used as a power module without replacing unit batteries as in the case of conventional primary unit batteries.

[0401] Example

[0402] Hereinafter, the present disclosure will be described by way of Examples and Comparative Examples. However, the present disclosure should not be construed as being limited to the Examples illustrated herein.

[0403] <Production Example 1: Synthesis of Polymer>

[0404] The polymer (A-05) represented by the following formula was synthesized by the following reaction.

[0405]

[0406] Note that "Et" represents an ethyl group. "n" represents an integer that allows the polymer (A-05) to have a weight average molecular weight of 20,000.

[0407] A 100-ml four-necked flask was charged with the above dialdehyde compound (0.66 g) (2.0 mmol) and diphosphonate (1.02 g) (2.0 mmol), and the resultant was purged with nitrogen, followed by addition of tetrahydrofuran (75 ml). 1.0 mol·dm -3 To the mixture was added a tetrahydrofuran solution of potassium tert-butoxide (6.75 ml) (6.75 mmol), followed by stirring at room temperature for 2 hours. Subsequently, diethylbenzylphosphonate and benzaldehyde were added thereto in sequence, followed by stirring for another 2 hours.

[0408] Acetic acid (about 1 ml) is added to complete the reaction, and the solution is washed with water. After removing the solvent under reduced pressure, tetrahydrofuran and methanol are used to reprecipitate the resulting product for purification, to obtain polymer (A-05) (0.95 g). The number average molecular weight of the polymer (A-05) measured by gel permeation chromatography (GPC) relative to polystyrene is 8,500, and the weight average molecular weight of the polymer (A-05) measured by gel permeation chromatography (GPC) relative to polystyrene is 20,000. The ionization potential measured using photoemission yield spectrometer AC-2 (obtained by RIKEN KEIKI Co., Ltd.) is 5.20 eV. All ionization potentials described below are the numerical values measured by AC-2.

[0409] (Example 1)

[0410] <Production of solar cell batteries>

[0411] An indium tin oxide (ITO) glass substrate was used as the substrate and the first electrode.

[0412] Tin oxide colloidal solution (obtained from Alfa Aesar) was applied to an ITO glass substrate, and heated and dried at 100° C. for 1 hour. Subsequently, 0.1 mM (wherein M means mol / dm) of tin oxide colloidal solution obtained by dissolving (1-aminoethyl)phosphonic acid (obtained from Aldrich) in ethanol was added. 3 ) solution was applied on the aforementioned film using a spin coating method and dried at 70° C. for 10 minutes to obtain an electron transport layer.

[0413] Subsequently, lead (II) iodide (0.5306 g), lead (II) bromide (0.0736 g), methylamine bromide (0.0224 g) and formamidine hydroiodide (0.1876 g) were added to N, N-dimethylformamide (0.8 ml) and dimethyl sulfoxide (0.2 ml), and heated at 60 ° C with stirring to obtain a solution. Subsequently, the solution was applied to the electron transport layer by spin coating, and chlorobenzene (0.3 ml) was added thereto to form a perovskite film. The perovskite film was dried at 150 ° C for 30 minutes to form a perovskite layer (photoelectric conversion layer). The average thickness of the perovskite layer was adjusted to 200 nm to 350 nm. Further, a 20 mM solution obtained by dissolving iodide-n-hexylamine in ethanol was applied to the formed perovskite layer by spin coating.

[0414] Subsequently, the polymer (A-05) produced in Production Example 1 (73.6 mg) and the additive represented by (B-14) (7.4 mg) were weighed and dissolved in chlorobenzene (3.0 ml). The resulting solution was applied to the deposited product obtained in the previous step by spin coating to form a hole transport layer. Note that the average thickness of the hole transport layer (the portion on the perovskite layer) was adjusted to 50 nm to 120 nm.

[0415] Furthermore, gold (100 nm) was evaporated on the deposited product under vacuum.

[0416] As a result, the solar battery unit cell 1 is obtained.

[0417] <<Evaluating the characteristics of solar cell units>>

[0418] A solar cell evaluation system (obtained from NF CORPORATION, product name: As-510-PV03) was used while a solar simulator emitting light (AM 1.5, 100 mW / cm 2 ), and the solar cell characteristics (initial characteristics) of the obtained solar cell 1 were evaluated. The results are shown in Table 2.

[0419] <Conversion efficiency maintenance rate>

[0420] The conversion efficiency maintenance rate (%) of the obtained solar cell unit cell 1 was determined. The conversion efficiency maintenance rate was obtained after continuous irradiation for 500 hours (AM 1.5, 100 mW / cm 2 The results are shown in Table 2.

[0421] (Examples 2 to 25)

[0422] Solar cell units of Examples 2 to 25 were produced and evaluated in the same manner as in Example 1, except that the polymer A and additive B used to form the hole transport layer, and the mass ratio (A:B) were changed to the polymer A, additive B, and mass ratio (A:B) of Examples 2 to 25 described in Table 2. The results are presented in Table 2.

[0423] (Comparative Example 1)

[0424] Solar cell units were produced and evaluated in the same manner as in Example 1, except that the additives were changed to lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) (10 mg) and 4-tert-butylpyridine (tBP) (13 mg). The results are shown in Table 2.

[0425] (Comparative Example 2)

[0426] Solar cell units were produced and evaluated in the same manner as in Example 1, except that the polymer used to form the hole transport layer was changed to the polymer described in Table 2. The results are presented in

[0427] Table 2.

[0428]

[0429]

[0430] In Table 2, the meanings of the symbols are as follows.

[0431] "Voc" means open circuit voltage

[0432] "Jsc" means short circuit current density.

[0433] "FF" means form factor.

[0434] "η" means photoelectric conversion efficiency.

[0435] "P3HT" in Comparative Example 2 is a polymer represented by the following structural formula (obtained from Aldrich).

[0436]

[0437] Here, n represents an integer of 1 or greater.

[0438] From the results in Table 2, it is found that the results of Examples 1 to 25 have good durability, as their initial characteristics are quite excellent, and the conversion efficiency maintenance rate obtained after 500 hours of continuous irradiation is 80% or more. At the same time, it is clear that the results of Comparative Examples 1 and 2 not only show low initial characteristics but also low conversion efficiency maintenance rate obtained after 500 hours of continuous irradiation.

[0439] As described above, when the hole transport layer includes a polymer containing a repeating unit represented by general formula (1) and a compound represented by general formula (2), the photoelectric conversion element of the present disclosure can maintain not only the initial characteristics but also the power generation efficiency even after being exposed to light of high illuminance for a long period of time.

[0440] (Reference Example 101)

[0441] <Production of solar cell batteries>

[0442] An indium tin oxide (ITO) glass substrate was used as the substrate and the first electrode.

[0443] Tin oxide colloidal solution (obtained from Alfa Aesar) was applied to an ITO glass substrate, and heated and dried at 100° C. for 1 hour. Subsequently, 0.1 mM (wherein M means mol / dm) of tin oxide colloidal solution obtained by dissolving (1-aminoethyl)phosphonic acid (obtained from Aldrich) in ethanol was applied to the substrate using a spin coating method. 3 ) solution was applied on the aforementioned film and dried at 70° C. for 10 minutes to obtain an electron transport layer.

[0444] Subsequently, lead (II) iodide (0.5306 g), lead (II) bromide (0.0736 g), methylamine bromide (0.0224 g) and formamidine hydroiodide (0.1876 g) were added to N, N-dimethylformamide (0.8 ml) and dimethyl sulfoxide (0.2 ml), and heated at 60 ° C with stirring to obtain a solution. The obtained solution was applied to the electron transport layer by spin coating, and chlorobenzene (0.3 ml) was added thereto to form a perovskite film. The perovskite film was dried at 150 ° C for 30 minutes to form a perovskite layer (photoelectric conversion layer). The average thickness of the perovskite layer was adjusted to 200 nm to 350 nm. Further, a 20 mM solution obtained by dissolving iodide-n-hexyltrimethylamine in ethanol was applied to the formed perovskite layer by spin coating.

[0445] Subsequently, the polymer (A-05) produced in Production Example 1 (73.6 mg) and 4-isopropyl-4′-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (7.4 mg) were weighed and dissolved in chlorobenzene (3.0 ml). The resulting solution was applied to the deposited product obtained in the previous step by spin coating to form a hole transport layer. Note that the average thickness of the hole transport layer (the portion on the perovskite layer) was adjusted to 50 nm to 120 nm.

[0446] Furthermore, gold (100 nm) was evaporated on the deposited product under vacuum.

[0447] As a result, solar battery unit cells 101 are obtained.

[0448] <<Evaluating the characteristics of solar cell units>>

[0449] A solar cell evaluation system (obtained from NF CORPORATION, product name: As-510-PV03) was used while a solar simulator emitting light (AM 1.5, 100 mW / cm 2 ), and the solar cell characteristics (initial characteristics) of the obtained solar cell 101 were evaluated. The results are shown in Table 3.

[0450] (Reference Examples 102 to 115)

[0451] Solar cell units were produced and evaluated in the same manner as in Reference Example 101, except that (1-aminoethyl)phosphonic acid and n-hexyltrimethylamine iodide were changed to the compounds described in Table 3. The results are shown in Table 3.

[0452] [Table 3]

[0453]

[0454] In Table 3, iodide-n-hexyltrimethylamine is n-hexylamine hydroiodide.

[0455] Bromide-n-hexyltrimethylammonium is n-hexylamine hydrobromide.

[0456] Phenethylamine iodide is 2-phenethylamine hydroiodide.

[0457] In Tables 3 and 4, the meanings of the symbols are as follows.

[0458] "Voc" means open circuit voltage.

[0459] "Jsc" means short circuit current density.

[0460] "FF" means form factor.

[0461] "η" means photoelectric conversion efficiency.

[0462] (Refer to Comparative Examples 101 to 104)

[0463] Solar cell units were produced and evaluated in the same manner as in Reference Example 101, except that (1-aminoethyl)phosphonic acid and n-hexyltrimethylamine iodide were changed to the compounds described in Table 4. The results are shown in Table 4.

[0464] [Table 4]

[0465]

[0466] As is clear from Reference Examples 101 to 115 and Reference Comparative Examples 101 and 102, when a phosphonic acid, sulfonic acid, halosilyl compound, or alkoxysilyl compound (hereinafter referred to as an "acid compound") is used and an organic or inorganic salt is inserted between the photoelectric conversion layer and the hole transport layer, the conversion efficiency is significantly higher than when the acid compound alone is used or when the organic or inorganic salt alone is used. Furthermore, as is clear from Reference Comparative Examples 103 and 104, the conversion efficiency does not increase even when a carboxylic acid is used as the acid compound.

[0467] Furthermore, as is clear from Reference Examples 101 to 104 and Reference Example 106, it is apparent that the use of a compound having an amino group as the acid compound increases the conversion efficiency.

[0468] Aspects of the present disclosure are, for example, as follows.

[0469] <1> A photoelectric conversion element comprising:

[0470] a first electrode;

[0471] electron transport layer;

[0472] Photoelectric conversion layer;

[0473] a hole transport layer; and

[0474] the second electrode,

[0475] wherein the electron transport layer comprises an electron transport material,

[0476] wherein the electron transport layer comprises at least one compound selected from the group consisting of a phosphonic acid compound, a boric acid compound, a sulfonic acid compound, a halosilyl compound, and an alkoxysilyl compound on the electron transport material on the surface of the electron transport layer on the side of the photoelectric conversion layer, and

[0477] The photoelectric conversion element contains at least one salt selected from organic salts and inorganic salts between the photoelectric conversion layer and the hole transport layer.

[0478] <2> according to <1> The photoelectric conversion element of claim 1, wherein the compound includes a nitrogen atom.

[0479] <3> according to <1> or <2> A photoelectric conversion element, wherein the compound is represented by the following general formula (3):

[0480]

[0481] Wherein R1 and R2 may be the same as or different from each other and represent a hydrogen atom, an alkyl group, an aryl group, or a heterocycle, R3 represents a divalent alkylene group, a divalent aryl group, or a divalent heterocycle, R4 represents a phosphonic acid group, a boronic acid group, a sulfonic acid group, a halosilyl group, or an alkoxysilyl group, and R1 or R2, R3, and N may be linked together to form a ring structure.

[0482] <4> according to <1> to <3> The photoelectric conversion element of any one of the items, wherein the salt includes a halogen atom as a cation.

[0483] <5> according to <1> to <3> The photoelectric conversion element according to any one of the preceding claims, wherein the organic salt is a hydrohalide salt of an amine, and the inorganic salt is a halide of an alkali metal.

[0484] <6> according to <1> to <5> The photoelectric conversion element according to any one of the preceding claims, wherein the photoelectric conversion layer is a perovskite layer including a perovskite compound.

[0485] <7> according to <6> A photoelectric conversion element, wherein the perovskite compound is represented by the following general formula (4):

[0486] X α Y β Z γ ···General formula (4)

[0487] wherein the ratio of α:β:γ is 3:1:1; β and γ are each an integer greater than 1; X represents a halogen atom; Y represents an organic compound including an amino group; and Z represents a metal ion.

[0488] <8> according to <1> to <7> The photoelectric conversion element of any one of the items, wherein the hole transport layer includes a polymer including a repeating unit represented by the following general formula (1):

[0489]

[0490] wherein Ar1 represents an aromatic hydrocarbon group, which may be substituted by a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group, which may be substituted by a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted by a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group, or an aryl group; and n represents an integer of 2 or greater that allows the polymer represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater.

[0491] <9> according to <1> to <8> Any photoelectric conversion element, wherein the electron transport material is a metal oxide.

[0492] <10> according to <9> The photoelectric conversion element of claim 1, wherein the metal oxide comprises tin oxide.

[0493] <11> according to <1> to <10> The photoelectric conversion element of any one of the items, wherein the roughness factor of the surface of the electron transport layer located on the photoelectric conversion layer side is 10 or less.

[0494] <12> A photoelectric conversion module comprising

[0495] Photoelectric conversion elements electrically coupled in series or in parallel, each photoelectric conversion element is based on <1> to <11> Any photoelectric conversion element

[0496] <13> Electronic equipment comprising:

[0497] according to <12> A photoelectric conversion module; and

[0498] A device configured to be driven by electric power generated by photoelectric conversion by a photoelectric conversion module.

[0499] <14> Electronic equipment comprising:

[0500] according to <12> Photoelectric conversion module;

[0501] a power storage device configured to store power generated by photoelectric conversion of the photoelectric conversion module; and

[0502] A device configured to be driven by at least one of electric power generated by photoelectric conversion in a photoelectric conversion module and electric power stored in an electric power storage device.

[0503] <15> A power module comprising:

[0504] according to <12> A photoelectric conversion module; and

[0505] Power supply integrated circuit.

[0506] according to <1> to <11> Any photoelectric conversion element, according to <12> Photoelectric conversion module, according to <13> or <14> electronic equipment, and <15> The power supply module can solve conventional problems and achieve the goals of the present disclosure.

[0507] <101> A photoelectric conversion element comprising:

[0508] First carrier;

[0509] a first electrode;

[0510] electron transport layer;

[0511] Photoelectric conversion layer;

[0512] a hole transport layer; and

[0513] the second electrode,

[0514] wherein the hole transport layer comprises a polymer comprising a repeating unit represented by the following general formula (1) and a compound represented by the following general formula (2):

[0515]

[0516] wherein, in the general formula (1), Ar1 represents an aromatic hydrocarbon group, and the aromatic hydrocarbon group may be substituted with a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group, which may be substituted with a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted with a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group, or an aryl group; and n represents an integer of 2 or greater that allows the polymer represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater; and

[0517]

[0518] Wherein in the general formula (2), R5 to R9 may be the same as or different from each other and represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group; and X represents a cation.

[0519] <102> according to <101> The photoelectric conversion element,

[0520] The mass ratio (A:B) between the polymer A including the repeating unit represented by the general formula (1) and the compound B represented by the general formula (2) is 20:1 to 1:1.

[0521] <103> according to <101> or <102> The photoelectric conversion element,

[0522] The photoelectric conversion layer includes a compound represented by the following general formula (4):

[0523] X α Y β Z γ ···General formula (4)

[0524] wherein the ratio of α:β:γ is 3:1:1; β and γ are each an integer greater than 1; X represents a halogen atom; Y represents an organic compound including an amino group; and Z represents a metal ion.

[0525] <104> according to <101> to <103> Any photoelectric conversion element,

[0526] The photoelectric conversion layer is a perovskite layer including a perovskite compound.

[0527] <105> according to <104> The photoelectric conversion element,

[0528] The perovskite layer includes Sb atoms, Cs atoms, Rb atoms, or K atoms.

[0529] <106> according to <101> to <105> The photoelectric conversion element of any one of the items, further comprising an amine compound between the photoelectric conversion layer and the hole transport layer, and the amine compound is different from the amine compound in the photoelectric conversion layer.

[0530] <107> according to <101> to <106> The photoelectric conversion element of any one of the items, wherein the electron transport layer includes tin oxide.

[0531] <108> A photoelectric conversion module comprising

[0532] Photoelectric conversion elements electrically coupled in series or in parallel, each photoelectric conversion element is based on <101> to <107> Any photoelectric conversion element.

[0533] <109> Electronic equipment comprising:

[0534] according to <108> A photoelectric conversion module; and

[0535] A device configured to be driven by electric power generated by photoelectric conversion by a photoelectric conversion module.

[0536] <110> Electronic equipment comprising:

[0537] according to <108> Photoelectric conversion module;

[0538] an electricity storage device configured to store electricity generated by photoelectric conversion of the photoelectric conversion module; and

[0539] A device configured to be driven by at least one of electric power generated by photoelectric conversion in a photoelectric conversion module and electric power stored in an electric power storage device.

[0540] <111> A power module comprising:

[0541] according to <108> A photoelectric conversion module; and

[0542] Power supply integrated circuit.

[0543] according to <101> to <107> Any photoelectric conversion element, according to <108> Photoelectric conversion module, according to <109> or <110> electronic equipment, and according to <111> The power supply module can solve conventional problems and achieve the goals of the present disclosure.

[0544] [Reference Symbol List]

[0545] 2 First electrode

[0546] 3 Dense electron transport layer (dense layer)

[0547] 5 Perovskite layer

[0548] 6 Hole Transport Layer

[0549] 7 Second electrode

[0550] 50 solar cell batteries

Claims

1. A photoelectric conversion element comprising: First carrier; a first electrode; electron transport layer; Photoelectric conversion layer; hole transport layer; and the second electrode, The hole transport layer comprises: a polymer comprising a repeating unit represented by the following general formula (1), and a compound represented by the following general formula (2): General formula (1) wherein, in the general formula (1), Ar1 represents an aromatic hydrocarbon group, and the aromatic hydrocarbon group may be substituted with a substituent; Ar2 and Ar3 each independently represent a divalent group of a monocyclic aromatic hydrocarbon group, a non-condensed polycyclic aromatic hydrocarbon group, or a condensed polycyclic aromatic hydrocarbon group, which may be substituted with a substituent; Ar4 represents a divalent group of benzene, thiophene, biphenyl, anthracene, or naphthalene, which may be substituted with a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group, or an aryl group; and n represents an integer of 2 or greater that allows the polymer represented by the general formula (1) to have a weight average molecular weight of 2,000 or greater; and General formula (2) Wherein, in the general formula (2), R5 to R9 may be the same as or different from each other and represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group; and X represents a cation, wherein the mass ratio A:B between the polymer A comprising a repeating unit represented by the general formula (1) and the compound B represented by the general formula (2) is 50:1 to 0.5:1, wherein the electron transport layer comprises, on the electron transport material on its surface on the side of the photoelectric conversion layer, at least one first compound selected from the group consisting of phosphonic acid compounds, boric acid compounds, sulfonic acid compounds, halosilyl compounds, and alkoxysilyl compounds, and The photoelectric conversion element comprises at least one salt selected from organic salts and inorganic salts between the photoelectric conversion layer and the hole transport layer, the organic salt and the inorganic salt contain a halogen atom as an anion, the organic salt is an amine hydrohalide, and the inorganic salt is an alkali metal halide.

2. The photoelectric conversion element according to claim 1, The mass ratio A:B between the polymer A containing the repeating unit represented by the general formula (1) and the compound B represented by the general formula (2) is 20:1 to 1:

1. The photoelectric conversion element according to claim 1 , wherein the first compound contains a nitrogen atom.

4. The photoelectric conversion element according to claim 3, wherein the first compound is represented by the following general formula (3): General formula (3) Wherein R1 and R2 may be the same as or different from each other and represent a hydrogen atom, an alkyl group, an aryl group, or a heterocycle, R3 represents a divalent alkylene group, a divalent aryl group, or a divalent heterocycle, R4 represents a phosphonic acid group, a boronic acid group, a sulfonic acid group, a halosilyl group, or an alkoxysilyl group, and R1 or R2, R3 and N may be connected together to form a ring structure.

5. The photoelectric conversion element according to claim 1 or 2, wherein the photoelectric conversion layer contains a compound represented by the following general formula (4): ・・・General formula (4) in The ratio is ; β and γ are each an integer greater than 1; X represents a halogen atom; Y represents an organic compound containing an amino group; and Z represents a metal ion. 6 . The photoelectric conversion element according to claim 1 , wherein the photoelectric conversion layer is a perovskite layer containing a perovskite compound.

7. The photoelectric conversion element according to claim 6, The perovskite layer contains Sb atoms, Cs atoms, Rb atoms, or K atoms.

8. The photoelectric conversion element according to claim 1 or 2, further comprising An amine compound between the photoelectric conversion layer and the hole transport layer, and the amine compound is different from the amine compound in the photoelectric conversion layer. 9 . The photoelectric conversion element according to claim 1 , wherein the electron transport layer comprises a metal oxide. 10 . The photoelectric conversion element according to claim 9 , wherein the metal oxide is tin oxide.

11. Photoelectric conversion module, comprising Photoelectric conversion elements electrically coupled in series or in parallel, each of the photoelectric conversion elements being the photoelectric conversion element according to any one of claims 1 to 10.

12. Electronic equipment comprising: The photoelectric conversion module according to claim 11; and A device configured to be driven by electric power generated by photoelectric conversion by a photoelectric conversion module.

13. Electronic equipment comprising: The photoelectric conversion module according to claim 11; an electricity storage device configured to store electricity generated by photoelectric conversion of the photoelectric conversion module; and A device configured to be driven by at least one of electric power generated by photoelectric conversion in a photoelectric conversion module and electric power stored in an electric power storage device.

14. A power module comprising: The photoelectric conversion module according to claim 11; and Power supply integrated circuit.

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