TW202348721A - Composition, film, organic photoelectric conversion element, and photodetection element - Google Patents

Abstract

The present invention addresses the problem of providing a composition capable of producing an active layer of a photoelectric conversion element exhibiting a reduced dark current. The present invention pertains to a composition containing a p-type semiconductor, an n-type semiconductor, a surfactant, and a solvent. The present invention pertains to a film containing a p-type semiconductor, an n-type semiconductor, and a surfactant. The present invention pertains to an organic photoelectric conversion element comprising a first electrode, said film, and a second electrode in this order. The present invention pertains to a photodetection element comprising said organic photoelectric conversion element.

Description

Compositions, films, organic photoelectric conversion elements and light detection elements

The invention relates to a composition, film, organic photoelectric conversion element and light detection element.

In recent years, organic photoelectric conversion elements containing organic compounds in the active layer have attracted much attention. Photodetection elements including organic photoelectric conversion elements are extremely useful elements from the viewpoints of energy saving and reduction of carbon dioxide emissions, for example, and are attracting attention. Attempts have also been made to improve the characteristics of a photodetection element including the organic photoelectric conversion element (see Non-Patent Document 1). [Prior Art Document] [Non-patent literature]

[Non-patent document 1] Yazhong Wang, et al., "Mater. Horiz.," 2022, 9, 220-251

[Problem to be solved by the invention] It is preferable that the photoelectric conversion element included in the photodetection element has a small current (dark current) flowing in a dark state. Therefore, a composition is sought that can produce an active layer of a photoelectric conversion element with reduced dark current; a film that can function as an active layer of a photoelectric conversion element with reduced dark current; an organic photoelectric conversion element including the film; A light detection element with reduced dark current includes the organic photoelectric conversion element. [Means to solve the problem]

The present inventors conducted diligent research in order to solve the above-mentioned problems, and as a result completed the present invention. The present invention provides the following.

[1] A composition including p-type semiconductor, n-type semiconductor, surfactant and solvent. [2] The composition according to [1], wherein the p-type semiconductor is a polymer compound having a donor/acceptor structure. [3] The composition according to [1] or [2], wherein the p-type semiconductor contains a structural unit selected from the group consisting of a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II) A polymer compound composed of more than one structural unit in a group. [Chemical 1] (In formula (I), Ar ¹ and Ar ² each independently represent a trivalent aromatic heterocyclic group which may have a substituent, and Z represents any one of the following formulas (Z-1) to formula (Z-7) The basis represented by . [Chemistry 2] (In Formula (Z-1) to Formula (Z-7), R represents: a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, A cycloalkenyl group which may have a substituent, an alkynyl group which may have a substituent, a cycloalkynyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, a cycloalkyl which may have a substituent Oxy group, aryloxy group which may have a substituent, alkylthio group which may have a substituent, cycloalkylthio group which may have a substituent, arylthio group which may have a substituent, monovalent heterocyclic group which may have a substituent , a substituted amino group which may have a substituent, an imine residue which may have a substituent, a amide group which may have a substituent, a amide group which may have a substituent, a substituted oxycarbonyl group which may have a substituent, cyanide A group, a nitro group, a group represented by -C(=O)-R ^c , or a group represented by -SO ₂ -R ^d , R ^c and R ^d each independently represent: a hydrogen atom, an alkane which may have a substituent group, a cycloalkyl group that may have a substituent, an aryl group that may have a substituent, an alkoxy group that may have a substituent, a cycloalkoxy group that may have a substituent, an aryloxy group that may have a substituent, or Monovalent heterocyclic group of substituent. In formula (Z-1) to formula (Z-7), when there are two R, the two R may be the same or different)) [Chemical 3] (In formula (II), Ar ³ represents a divalent aromatic heterocyclic group) [4] The composition according to any one of [1] to [3], wherein the n-type semiconductor is a fullerene-derived things. [5] The composition according to any one of [1] to [3], wherein the n-type semiconductor is a non-fullerene compound. [6] The composition according to any one of [1] to [5], wherein the solvent contains an aromatic hydrocarbon solvent. [7] The composition according to any one of [1] to [6], wherein the surfactant is a nonionic surfactant. [8] The composition according to any one of [1] to [7], wherein the surfactant is a compound having a poly(meth)acrylate structure. [9] The composition according to any one of [1] to [8], wherein the surfactant is a compound having an organopolysiloxane structure. [10] The composition according to any one of [1] to [9], wherein the surfactant is a fluorine-based surfactant. [11] A film including a p-type semiconductor, an n-type semiconductor and a surfactant. [12] An organic photoelectric conversion element, including a first electrode, the film according to [11], and a second electrode in order. [13] A light detection element including the organic photoelectric conversion element described in [12]. [Effects of the invention]

According to the present invention, it is possible to provide: a composition capable of producing an active layer of a photoelectric conversion element with reduced dark current; a film capable of functioning as an active layer of a photoelectric conversion element with reduced dark current; and an organic photoelectric conversion element including the above The film; a light detection element with reduced dark current, including the organic photoelectric conversion element.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the drawings only schematically show the shapes, sizes, and arrangements of the constituent elements to an extent that allows the invention to be understood. The present invention is not limited to the following description, and each constituent element can be appropriately changed within the scope of the spirit of the present invention. In the drawings used for the following description, the same components are denoted by the same symbols, and repeated descriptions may be omitted. In addition, the structure of the embodiment of the present invention is not necessarily limited to the configuration illustrated in the drawings. The constituent elements of the embodiments shown below can be combined as appropriate.

[1. Explanation of common terms] In this specification, a "polymer compound" refers to a polymer having a molecular weight distribution and a number average molecular weight in terms of polystyrene of 1×10 ³ or more and 1×10 ⁸ or less. The total number of structural units contained in the polymer compound is 100 mol%.

In this specification, the so-called "structural unit" refers to the presence of one or more units in the polymer compound. The "monomer unit" refers to a unit having a structure obtainable by polymerizing the monomer (monomer). The "single volume unit" is not limited by the manufacturing method.

In this specification, "hydrogen atom" can be a light hydrogen atom or a heavy hydrogen atom.

In this specification, examples of "halogen atoms" include fluorine atoms, chlorine atoms, bromine atoms and iodine atoms.

The form of "may have a substituent" includes two forms: a case in which all the hydrogen atoms constituting the compound or group are unsubstituted, and a case in which one or more hydrogen atoms are partially or entirely substituted with a substituent.

Examples of the substituent include: halogen atom, alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, alkoxy group, cycloalkoxy group, alkylthio group, cycloalkylthio group , aryl group, aryloxy group, arylthio group, monovalent heterocyclic group, hydroxyl group, carboxyl group, substituted amine group, acyl group, imine residue, amide group, amide imine group, substituted oxycarbonyl group, cyano group , alkylsulfonyl group, and nitro group.

In this specification, "alkyl" may have a substituent. Unless otherwise specified, the "alkyl group" may be either linear or branched. The number of carbon atoms of the linear alkyl group does not include the number of carbon atoms of the substituent, and is usually 1 to 50, preferably 1 to 30, and more preferably 1 to 20. The number of carbon atoms of the branched or cyclic alkyl group does not include the number of carbon atoms of the substituent, and is usually 3 to 50, preferably 3 to 30, and more preferably 4 to 20.

Specific examples of the alkyl group include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, and 2-ethylbutyl base, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, 3-n-propylheptyl, n-decyl, 3,7-dimethyloctyl, 2-ethyloctyl, 2- n-hexyl-decyl, n-dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl and other unsubstituted alkyl groups; trifluoromethyl, pentafluoroethyl, all Fluorobutyl, perfluorohexyl, perfluorooctyl, 3-phenylpropyl, 3-(4-methylphenyl)propyl, 3-(3,5-di-n-hexylphenyl)propyl, Substituted alkyl groups such as 6-ethoxyhexyl, cyclohexylmethyl, cyclohexylethyl, etc.

"Cycloalkyl" may be a monocyclic group or a polycyclic group. The cycloalkyl group may have a substituent. The number of carbon atoms of the cycloalkyl group does not include the number of carbon atoms of the substituent, and is usually 3 to 30, preferably 3 to 20.

Examples of the cycloalkyl group include unsubstituted alkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and adamantyl, and hydrogen atoms in these groups are substituted by alkyl, alkoxy, aryl, etc. A group substituted by a substituent such as a base or a fluorine atom.

Specific examples of the cycloalkyl group having a substituent include methylcyclohexyl and ethylcyclohexyl.

"Alkenyl" may be linear or branched. The alkenyl group may have a substituent. The number of carbon atoms of the alkenyl group does not include the number of carbon atoms of the substituent, and is usually 2 to 30, preferably 2 to 20.

Examples of the alkenyl group include vinyl, 1-propenyl, 2-propenyl, 2-butenyl, 3-butenyl, 3-pentenyl, 4-pentenyl, and 1-hexenyl. groups, alkenyl groups without substituents such as 5-hexenyl and 7-octenyl groups, and groups in which hydrogen atoms in these groups are substituted by substituents such as alkoxy groups, aryl groups and fluorine atoms.

"Cycloalkenyl" may be a monocyclic group or a polycyclic group. The cycloalkenyl group may have a substituent. The number of carbon atoms of the cycloalkenyl group does not include the number of carbon atoms of the substituent, and is usually 3 to 30, preferably 3 to 20.

Examples of cycloalkenyl groups include unsubstituted cycloalkenyl groups such as cyclohexenyl groups, and cycloalkenyl groups in which hydrogen atoms are substituted with substituents such as alkyl groups, alkoxy groups, aryl groups, and fluorine atoms. The basis of success.

Examples of the cycloalkenyl group having a substituent include methylcyclohexenyl and ethylcyclohexenyl.

"Alkynyl" may be linear or branched. The alkynyl group may have a substituent. The number of carbon atoms of the alkynyl group does not include the number of carbon atoms of the substituent, and is usually 2 to 30, preferably 2 to 20.

Examples of the alkynyl group include: ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, 3-butynyl, 3-pentynyl, 4-pentynyl, 1- Alkynyl groups without substituents such as hexynyl and 5-hexynyl groups, and groups in which hydrogen atoms in these groups are substituted with substituents such as alkoxy groups, aryl groups, and fluorine atoms.

"Cycloalkynyl" may be a monocyclic group or a polycyclic group. The cycloalkynyl group may have a substituent. The number of carbon atoms of the cycloalkynyl group does not include the number of carbon atoms of the substituent, and is usually 4 to 30, preferably 4 to 20.

Examples of cycloalkynyl groups include unsubstituted cycloalkynyl groups such as cyclohexynyl groups, and hydrogen atoms in these groups substituted by substituents such as alkyl groups, alkoxy groups, aryl groups, and fluorine atoms. The base.

Examples of the cycloalkynyl group having a substituent include methylcyclohexynyl and ethylcyclohexynyl.

The "alkoxy group" may be linear or branched. The alkoxy group may have a substituent. The number of carbon atoms of the alkoxy group does not include the number of carbon atoms of the substituent, and is usually 1 to 30, preferably 1 to 20.

Examples of the alkoxy group include: methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, n-pentoxy, n-hexyl Oxygen, n-heptyloxy, n-octyloxy, 2-ethylhexyloxy, n-nonyloxy, n-decyloxy, 3,7-dimethyloctyloxy, 3-heptyldodecyloxy alkoxy groups without substituents, such as alkoxy groups, lauryloxy groups, etc., and groups in which hydrogen atoms in these groups are substituted with substituents such as alkoxy groups, aryl groups, and fluorine atoms.

The cycloalkyl group contained in the "cycloalkoxy group" may be a monocyclic group or a polycyclic group. The cycloalkoxy group may have a substituent. The number of carbon atoms of the cycloalkoxy group does not include the number of carbon atoms of the substituent, and is usually 3 to 30, preferably 3 to 20.

Examples of the cycloalkoxy group include unsubstituted cycloalkoxy groups such as cyclopentyloxy, cyclohexyloxy, and cycloheptyloxy, and hydrogen atoms in these groups are replaced by fluorine atoms, alkyl groups, etc. A base substituted by a substituent.

The "alkylthio group" may be linear or branched. The alkylthio group may have a substituent. The number of carbon atoms of the alkylthio group does not include the number of carbon atoms of the substituent, and is usually 1 to 30, preferably 1 to 20.

Examples of the alkylthio group which may have a substituent include methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, tert-butylthio, n- Pentylthio, n-hexylthio, n-heptylthio, n-octylthio, 2-ethylhexylthio, n-nonylthio, n-decylthio, 3,7-dimethyloctylthio, 3-heptyl Dodecylthio, laurylthio and trifluoromethylthio.

The cycloalkyl group contained in the "cycloalkylthio group" may be a monocyclic group or a polycyclic group. The cycloalkylthio group may have a substituent. The number of carbon atoms of the cycloalkylthio group does not include the number of carbon atoms of the substituent, and is usually 3 to 30, preferably 3 to 20.

Examples of the cycloalkylthio group which may have a substituent include a cyclohexylthio group.

A "p-valent aromatic carbocyclic group" refers to an atomic group remaining after removing p hydrogen atoms directly bonded to carbon atoms constituting the ring from an aromatic hydrocarbon which may have a substituent. Aromatic hydrocarbons also include compounds having condensed rings, and compounds in which two or more selected from the group consisting of independent benzene rings and condensed rings are bonded directly or via a divalent group such as a vinyl vinyl group. The p-valent aromatic carbocyclic group may further have a substituent.

"Aryl" refers to a monovalent aromatic carbocyclic group. The aryl group may have a substituent. The number of carbon atoms of the aryl group does not include the number of carbon atoms of the substituent, and is usually 6 to 60, preferably 6 to 48.

Examples of the aryl group include: phenyl, 1-naphthyl, 2-naphthyl, 1-anthracenyl, 2-anthracenyl, 9-anthracenyl, 1-pyrenyl, 2-pyrenyl, 4-pyrene base, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, 2-phenylphenyl, 3-phenylphenyl, 4-phenylphenyl and other unsubstituted aryl groups, and these groups A group in which hydrogen atoms are substituted by substituents such as alkyl groups, alkoxy groups, aryl groups, and fluorine atoms.

The "aryloxy group" may have a substituent. The number of carbon atoms of the aryloxy group does not include the number of carbon atoms of the substituent, and is usually 6 to 60, preferably 6 to 48.

Examples of the aryloxy group include: phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 1-anthracenyloxy group, 9-anthracenyloxy group, 1-pyrenyloxy group and the like. Aryloxy groups having substituents, and groups in which hydrogen atoms in these groups are substituted by substituents such as alkyl groups, alkoxy groups, and fluorine atoms.

The "arylthio group" may have a substituent. The number of carbon atoms of the arylthio group does not include the number of carbon atoms of the substituent, and is usually 6 to 60, preferably 6 to 48.

Examples of the arylthio group which may have a substituent include: phenylthio group, C1 to C12 alkoxyphenylthio group, C1 to C12 alkylphenylthio group, 1-naphthylthio group, 2-naphthylthio group and Pentafluorophenylthio. "C1-C12" means that the number of carbon atoms of the group described next is 1-12. Furthermore, "Cm～Cn" means that the number of carbon atoms of the group described immediately after it is m～n. Same below.

"p-valent heterocyclic group" (p represents an integer of 1 or more) refers to a heterocyclic compound that may have a substituent except p hydrogen atoms directly bonded to carbon atoms or heteroatoms constituting the ring. remaining atoms. "p-valent aromatic heterocyclic group" includes "p-valent aromatic heterocyclic group". A "p-valent aromatic heterocyclic group" refers to an atomic group remaining after removing p hydrogen atoms directly bonded to carbon atoms or heteroatoms constituting the ring from an aromatic heterocyclic compound which may have a substituent.

Aromatic heterocyclic compounds include, in addition to compounds in which the heterocycle itself exhibits aromaticity, compounds in which the heterocycle itself does not exhibit aromaticity but has an aromatic ring condensed into the heterocycle.

Among aromatic heterocyclic compounds, specific examples of compounds in which the heterocycle itself exhibits aromaticity include: oxadiazole, thiadiazole, thiazole, oxazole, thiophene, pyrrole, phosphocyclopentadiene, and furan , pyridine, pyrazine, pyrimidine, triazine, pyridazine, quinoline, isoquinoline, carbazole and dibenzophospholane.

Among the aromatic heterocyclic compounds, specific examples of compounds in which the heterocyclic ring itself does not exhibit aromaticity but has an aromatic ring condensed on the heterocyclic ring include: phenoxazine, phenthiazine, and dibenzoborane heterocyclic ring Pentadiene, dibenzosilole and benzopyran.

The p-valent heterocyclic group may have a substituent. The number of carbon atoms of the p-valent heterocyclic group does not include the number of carbon atoms of the substituent, and is usually 2 to 60, preferably 2 to 20.

Examples of the monovalent heterocyclic group include: monovalent aromatic heterocyclic groups (such as thienyl, pyrrolyl, furyl, pyridyl, quinolyl, isoquinolyl, pyrimidinyl, triazinyl), Monovalent non-aromatic heterocyclic groups (such as piperidinyl, piperazinyl), and groups in which hydrogen atoms in these groups are substituted by substituents such as alkyl groups, alkoxy groups, and fluorine atoms.

"Substituted amine group" means an amine group having a substituent. As the substituent of the amino group, an alkyl group, a cycloalkyl group, an aryl group, and a monovalent heterocyclic group are preferred. The number of carbon atoms of the substituted amine group does not include the number of carbon atoms of the substituent, and is usually 2 to 30.

Examples of the substituted amino group include dialkylamino groups (such as dimethylamino group, diethylamino group), diarylamine groups (such as diphenylamine group, bis(4-methylbenzene) base) amino group, bis(4-tert-butylphenyl)amino group, bis(3,5-di-tert-butylphenyl)amino group).

The "acyl group" may have a substituent. The number of carbon atoms of the acyl group does not include the number of carbon atoms of the substituent, and is usually 2 to 20, preferably 2 to 18. Specific examples of the acyl group include an acetyl group, a propyl group, a butyl group, an isobutyl group, a trimethylacetyl group, a benzoyl group, a trifluoroacetyl group, and a pentafluorobenzoyl group.

"Imine residue" refers to an atomic group remaining from an imine compound after removing a hydrogen atom directly bonded to a carbon atom or a nitrogen atom constituting a carbon atom-nitrogen atom double bond. "Imine compound" refers to an organic compound having a carbon atom-nitrogen atom double bond in the molecule. Examples of imine compounds include aldimines, ketimines, and aldimines in which a hydrogen atom bonded to a nitrogen atom constituting a carbon atom-nitrogen atom double bond is substituted by an alkyl group, a cycloalkyl group, or the like. Substituted compounds.

The number of carbon atoms of the imine residue is usually 2 to 20, preferably 2 to 18. Examples of the imine residue include groups represented by the following structural formulas.

[Chemical 4]

"Camide group" refers to the atomic group remaining after removing a hydrogen atom bonded to a nitrogen atom from amide. The number of carbon atoms of the amide group is usually about 1 to 20, preferably 1 to 18. Specific examples of the amide group include a formamide group, an acetamide group, a propionamide group, a butylamide group, a benzamide group, a trifluoroacetamide group, and a pentafluorobenzamide group. base, dimethylamide group, diethylamide group, dipropylamide group, dibutylamide group, diphenylamide group, di-trifluoroacetamide group, and di-pentafluorobenzamide group Amino group.

"Cardimide group" refers to the atomic group remaining after removing a hydrogen atom bonded to a nitrogen atom from acylimine. The number of carbon atoms of the amide group is usually 4 to 20. Specific examples of the acyl imine group include the groups shown below.

[Chemistry 5]

"Substituted oxycarbonyl group" means a group represented by R'-O-(C=O)-. Here, R' represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or a monovalent heterocyclic group, and these groups may have a substituent. The number of carbon atoms of the substituted oxycarbonyl group is usually 2 to 60, preferably 2 to 48 carbon atoms.

Specific examples of the substituted oxycarbonyl group include: methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, isopropoxycarbonyl group, butoxycarbonyl group, isobutoxycarbonyl group, and tert-butoxycarbonyl group , pentyloxycarbonyl, hexyloxycarbonyl, cyclohexyloxycarbonyl, heptyloxycarbonyl, octyloxycarbonyl, 2-ethylhexyloxycarbonyl, nonyloxycarbonyl, decyloxycarbonyl, 3,7- Dimethyloctyloxycarbonyl, dodecyloxycarbonyl, trifluoromethoxycarbonyl, pentafluoroethoxycarbonyl, perfluorobutoxycarbonyl, perfluorohexyloxycarbonyl, perfluorooctyloxycarbonyl , phenoxycarbonyl, naphthyloxycarbonyl, and pyridyloxycarbonyl.

"Alkylsulfonyl group" may be linear or branched. The alkylsulfonyl group may have a substituent. The number of carbon atoms of the alkylsulfonyl group does not include the number of carbon atoms of the substituent, and is usually 1 to 30. Specific examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group and a dodecylsulfonyl group.

The "*" marked in the chemical formula indicates the bond.

The so-called "π conjugated system" refers to a system in which π electrons exist non-locally on multiple bonds.

"(Meth)acrylic group" includes an acrylic group, a methacrylic group, and a combination thereof.

"(Meth)acrylate" includes acrylate, methacrylate, and combinations thereof.

In the chemical formula, "Me" represents methyl, "Et" represents ethyl, and "Bu" represents butyl.

"Solvent" can be a dispersion medium.

[2.Composition] A composition according to an embodiment of the present invention includes a p-type semiconductor, an n-type semiconductor, a surfactant and a solvent. In addition to p-type semiconductors, n-type semiconductors, surfactants and solvents, the composition may also contain any components as needed.

The composition may be a solution or a dispersion such as a dispersion, emulsion (emulsion), suspension (suspension), etc.

The dark current of the photoelectric conversion element including the film obtained from the composition of this embodiment is reduced.

[2.1. Surfactant] Surfactant refers to a substance that changes the properties of the interface by adding it. Surfactants usually have both a hydrophilic group and a hydrophobic group in one molecule.

When the composition of this embodiment contains a surfactant, dark current of a photoelectric conversion element including a film obtained from the composition can be effectively reduced.

The reason why the dark current of the photoelectric conversion element can be effectively reduced by including the surfactant in the composition of the present embodiment does not limit the present invention, but is presumed as follows.

Usually, a composition is applied to a coating object such as an electrode or an intermediate layer to form a coating film, and then the coating film is dried to form a film (active layer). It is thought that the surfactant exists in the form of a film on the surface of the coating film, and that after the coating film dries, the surfactant preferentially present on the surface of the coating film directly segregates and solidifies. As a result, it is considered that a thin film of surfactant exists on the surface of the obtained film (active layer), functions as an insulating layer, and reduces dark current of the photoelectric conversion element.

Alternatively, it is thought that the phase separation structure that can be formed from a p-type semiconductor and an n-type semiconductor changes due to the action of a surfactant, and that this change reduces the dark current of the photoelectric conversion element.

As a surfactant that can effectively reduce the dark current of a photoelectric conversion element including a film obtained from the composition of this embodiment, a suitable interface activity can be selected by appropriately selecting the types of hydrophilic groups and hydrophobic groups in the molecules. agent.

Among the surfactants contained in the composition of this embodiment, when selecting a type of hydrophilic group, it is preferable to use a surfactant classified as non-ionic. As the solvent contained in the composition of this embodiment, a non-aqueous solvent such as an aromatic hydrocarbon solvent can be used. In terms of excellent solubility in a solvent, nonionic surfactants are also preferred. Examples of the hydrophilic group include groups having an epoxy group such as ethylene oxide or propylene oxide, an amine group, a ketone group, a carboxyl group, a sulfonic acid group, and the like. The surfactant may have one or two or more groups selected from these as a hydrophilic group.

Among the surfactants contained in the composition of this embodiment, when selecting from the type of hydrophobic group, examples of the hydrophobic group include: acrylic surfactants having a poly(meth)acrylate structure, organic polysilicon Silicone-based surfactants with an oxyalkane structure, and fluorine-based surfactants in which some or all of the hydrogen atoms contained in these groups are substituted with fluorine atoms.

In one embodiment, the surfactant preferably has a poly(meth)acrylate structure. Here, the poly(meth)acrylate structure is a structure represented by the following formula (SF-1). Because the composition has a poly(meth)acrylate structure, the dark current of the photoelectric conversion element can be effectively reduced. In addition to the poly(meth)acrylate structure, the surfactant may also contain any structural units. The surfactant with a poly(meth)acrylate structure can be an oligomer or a polymer.

[Chemical 6]

In formula (SF-1), multiple R ^sf1 each independently represent a hydrogen atom or a methyl group. The presence of multiple R ^sf2 each independently represents an organic group. Two or more of the plurality of R ^sf2 may together form a cross-linking group. R ^sf2 preferably independently represents an alkyl group, a cycloalkyl group, an alkoxyalkyl group, a group having a polyoxyalkylene group, an aryl group, an arylalkyl group, or an aryloxyalkyl group. These groups may also be Has a substituent (such as a fluorine atom). Preferable specific examples of the alkyl group represented by R ^sf2 include a fluorine atom-substituted alkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom (for example, difluoromethyl, 2,2-difluoromethyl Ethyl, 2,2,2-trifluoroethyl, 2,2,3,3-tetrafluoropropyl, 3,3,3-trifluoropropyl, 2,2,3,3,4,4- Hexafluorobutyl, 1,1-dimethyl-2,2,3,3-tetrafluoropropyl, 1,1-dimethyl-2,2,3,3-pentafluoropropyl, 2-( Perfluoropropyl)ethyl, 2,2,3,3,4,4,5,5-octafluoropentyl, 1,1-dimethyl-2,2,3,3,4,4-hexyl Fluorobutyl, 1,1-dimethyl-2,2,3,3,4,4,4-heptafluorobutyl, 2-(perfluorobutyl)ethyl, 2,2,3,3, 4,4,5,5,6,6-decafluorohexyl, perfluoropentylmethyl, 1,1-dimethyl-2,2,3,3,4,4,5,5-octafluoropentyl base, 1,1-dimethyl-2,2,3,3,4,4,5,5,5-nonafluoropentyl, 2-(perfluoropentyl)ethyl, 2,2,3, 3,4,4,5,5,6,6,7,7-dodecafluoropentyl, perfluorohexylmethyl, 2-(perfluorohexyl)ethyl, 2,2,3,3,4, 4,5,5,6,6,7,7,8,8-Tetradecafluorooctyl, perfluoroheptylmethyl, 2-(perfluoroheptyl)ethyl, 2,2,3,3, 4,4,5,5,6,6,7,7,8,8,9,9-Hexafluorononyl, perfluorooctylmethyl, 2-(perfluorooctyl)ethyl, 2, 2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10-octadecylfluorodecyl, perfluorononylmethyl, 2,2 ,3,4,4,4-hexafluorobutyl, 2,2,3,3,4,4,4-heptafluorobutyl, 3,3,4,4,5,5,6,6,6 - nonafluorohexyl, 3,3,4,4,5,5,6,6,7,7,8,8,8-dodecafluorooctyl), all hydrogen atoms in the alkyl group are replaced with fluorine atoms fluorine atom substituted alkyl (perfluoroalkyl) (such as trifluoromethyl, pentafluoroethyl, heptafluoro-n-propyl, heptafluoroisopropyl, nonafluoro-n-butyl, nonafluoroisobutyl, Nonafluoro-second butyl, nonafluoro-tertiary butyl, perfluoropentyl, perfluorohexyl, perfluoroheptyl, perfluorooctyl, perfluorononyl, perfluorodecyl).

In formula (SF-1), n (number of repeating units) is, for example, 2 or more, 3 or more, 4 or more, 5 or more, 10 or more, and is, for example, 3000 or less.

As the surfactant having a poly(meth)acrylate structure, commercially available products can be used. Examples of commercially available nonionic surfactants having a poly(meth)acrylate structure include: "F-556", "R-40", "MEGAFACE F-110" ”, “MEGAFACE F-113 (MEGAFACE F-113)”, “MEGAFACE F-120 (MEGAFACE F-120)”, “MEGAFACE F-812 (MEGAFACE F-812)”, “MEGAFACE F-142D (MEGAFACE F-142D)", "MEGAFACE F-144D (MEGAFACE F-144D)", "MEGAFACE F-150 (MEGAFACE F-150)", "MEGAFACE F-171 (MEGAFACE F-171)", "MEGAFACE F-173", "MEGAFACE F-177", "MEGAFACE F-183", "MEGAFACE F-195" F-195)", "MEGAFACE F-824 (MEGAFACE F-824)", "MEGAFACE F-833 (MEGAFACE F-833)", "MEGAFACE F-114 (MEGAFACE F-114)", "MEGAFACE F-824 "MEGAFACE F-410", "MEGAFACE F-493", "MEGAFACE F-494", "MEGAFACE F-443" 443)", "MEGAFACE F-444 (MEGAFACE F-444)", "MEGAFACE F-445 (MEGAFACE F-445)", "MEGAFACE F-446 (MEGAFACE F-446)", "MEGAFACE F-446" -470 (MEGAFACE F-470)", "MEGAFACE F-471 (MEGAFACE F-471)", "MEGAFACE F-474 (MEGAFACE F-474)", "MEGAFACE F-475 (MEGAFACE F-475)" ”, “MEGAFACE F-477 (MEGAFACE F-477)”, “MEGAFACE F-478 (MEGAFACE F-478)”, “MEGAFACE F-479 (MEGAFACE F-479)”, “MEGAFACE F-480SF (MEGAFACE F-480SF)", "MEGAFACE F-482 (MEGAFACE F-482)", "MEGAFACE F-483 (MEGAFACE F-483)", "MEGAFACE F-484 (MEGAFACE F-484)", "MEGAFACE F-486", "MEGAFACE F-487", "MEGAFACE F-489", "MEGAFACE F-172D" F-172D)", "MEGAFACE F-178K (MEGAFACE F-178K)", "MEGAFACE F-178RM (MEGAFACE F-178RM)", "MEGAFACE R-08 (MEGAFACE R-08)", "MEGAFACE R-08 "MEGAFACE R-30", "MEGAFACE F-472SF", "MEGAFACE BL-20", "MEGAFACE R-61" 61)", "MEGAFACE R-90 (MEGAFACE R-90)", "MEGAFACE ESM-1 (MEGAFACE ESM-1)", "MEGAFACE MCF-350SF (MEGAFACE MCF-350SF)" (the above is Dickson (manufactured by DIC company), "Ftergent 100", "Ftergent 100C", "Ftergent 110", "Ftergent 150", "Ftergent 150CH", "Ftergent A", "Ftergent 100A-K", "Ftergent 501", "Ftergent 300", "Ftergent 310" ”, “Ftergent 320”, “Ftergent 400SW”, “FTX-400P”, “Ftergent 251”, “Ftergent 215M”, “FTX-400P” "Ftergent 212MH", "Ftergent 250", "Ftergent 222F", "Ftergent 212D", "FTX-218", "FTX-209F", "FTX-213F", "FTX-233F", "Ftergent 245F", "FTX-208G", "FTX-240G", "FTX-206D", "FTX-220D", "FTX-230D" ", "FTX-240D", "FTX-207S", "FTX-211S", "FTX-220S", "FTX-230S", "FTX-750FM", "FTX-730FM", "FTX-730FL", "FTX-710FS", "FTX-710FM", "FTX-710FL", "FTX-750LL", "FTX-730LS", "FTX-730LM", "FTX-730LL", "FTX-710LL" (the above are Manufactured by NEOS Corporation), "BYK-300", "BYK-302", "BYK-306", "BYK-307", "BYK-310", "BYK-315", "BYK-320", "BYK-322", "BYK-323", "BYK-325", "BYK-330", "BYK-331", "BYK-333", "BYK-337", "BYK-340", "BYK (BYK)-344", "BYK (BYK)-370", "BYK (BYK)-375", "BYK (BYK)-377", "BYK (BYK)-350", "BYK-352", "BYK-354", "BYK-355", "BYK-356", "BYK-358N", "BYK-361N", "BYK-357", "BYK-390", "BYK-392", "BYK-UV3500", "BYK-UV3510", "BYK-UV3570", "BYK-Silclean 3700" (the above are manufactured by BYK-Chemie Japan), "TEGO Rad 2100", "TEGO Rad 2200 N", "TEGO Rad 2250", "TEGO Rad 2300", " "TEGO Rad 2500", "TEGO Rad 2600", "TEGO Rad 2700" (the above are manufactured by Evonik Industries).

In one embodiment, the surfactant preferably has an organopolysiloxane structure. Here, the organopolysiloxane structure is a structure represented by the following formula (SF-2). Because the composition has an organic polysiloxane structure, the dark current of the photoelectric conversion element can be effectively reduced. In addition to the organopolysiloxane structure, the surfactant may also contain any structural units. The surfactant with an organopolysiloxane structure can be an oligomer or a polymer.

[Chemical 7]

In the formula (SF-2), the plurality of R ^sf3 each independently represents an organic group. R ^sf3 preferably each independently represents an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, a group having a polyoxyalkylene group, or a group having a structure represented by -(C=O)-O- ( For example, groups having one or more, two or more, or three or more structures represented by -(C=O)-O-), and these groups may have substituents.

The surfactant having an organopolysiloxane structure may have any terminal group. Examples of terminal groups that the surfactant having an organopolysiloxane structure may have include an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, a group having a polyoxyalkylene group, and an aryl group. Arylalkyl groups and poly(meth)acrylyl groups, these groups may also have substituents (such as fluorine atoms).

In formula (SF-2), the range of n (number of repeating units) is, for example, 2 or more, 3 or more, 4 or more, 5 or more, 10 or more, and, for example, 3000 or less.

As the surfactant having an organopolysiloxane structure, commercially available products can be used. Examples of commercially available nonionic surfactants having an organopolysiloxane structure include: Product names "BYK-300", "BYK-301/302", "BYK-306", "BYK-307", "BYK" -310", "BYK (BYK) -315", "BYK (BYK) -313", "BYK (BYK) -320", "BYK (BYK) -322", "BYK (BYK) -323", "BYK (BYK) -325", "BYK (BYK) -330", "BYK (BYK) -331", "BYK (BYK) -333", "BYK (BYK) -337", "BYK-341", "BYK-344", "BYK-345/346", "BYK-347", "BYK BYK-348", "BYK-349", "BYK-370", "BYK-375", "BYK-377", "BYK BYK)-378", "BYK (BYK)-UV3500", "BYK (BYK)-UV3510", "BYK (BYK)-UV3570", "BYK (BYK)-3550", "BYK (BYK)-UV3510" (BYK-SILCLEAN) 3700", "BYK-SILCLEAN (3720)" (the above are manufactured by BYK-Chemie Japan), Trade names "AC FS 180", "AC FS 360", "AC S 20" (the above are manufactured by Algin Chemie), trade names "Polyflow (Polyflow) KL-400X", "Polyflow" "Polyflow KL-400HF", "Polyflow KL-401", "Polyflow KL-402", "Polyflow KL-403", " Polyflow KL-404", "Polyflow KL-700" (the above are manufactured by Kyoeisha Chemical Co., Ltd.), Product names "KP-301", "KP-306", "KP-109", "KP-310", "KP-310B", "KP-323", "KP-326", "KP-341", "KP-104", "KP-110", "KP-112", "KP-360A", "KP-361", "KP-354", "KP-355", "KP-356", "KP -357", "KP-358", "KP-359", "KP-362", "KP-365", "KP-366", "KP-368", "KP-369", "KP-330 ”, “KP-620”, “KP-625”, “KP-650”, “KP-651”, “KP-390”, “KP-391”, “KP-392” (the above is Shin-Etsu Chemical Industry Co., Ltd. manufacturing), Product names "LP-7001", "LP-7002", "SH28PA", "8032 ADDITIVE", "57 ADDITIVE", "L-7604", "FZ-2110" ”, “FZ-2105”, “67 ADDITIVE”, “8618ADDITIVE”, “3ADDITIVE”, “56ADDITIVE” ” (The above are manufactured by Toray Dow Corning), “TEGO WET 270” (manufactured by Evonik Degussa Japan), “NBX-15” (Nay Manufactured by NEOS Corporation).

In one embodiment, the surfactant is preferably a fluorine-based surfactant. Here, the fluorine-based surfactant refers to a surfactant containing a fluorine atom in its molecule. Since the composition contains a fluorine-based surfactant, the dark current of the photoelectric conversion element can be effectively reduced.

As the fluorine-based surfactant, commercially available products can be used. Examples of commercially available fluorine-based surfactants include: "F-556", "R-40", MEGAFACE F171, MEGAFACE F172, MEGAFACE F173, MEGAFACE (MEGAFACE) F176, MEGAFACE F177, MEGAFACE F141, MEGAFACE F142, MEGAFACE F143, MEGAFACE F144, MEGAFACE R30, MEGAFACE ( MEGAFACE) F437, MEGAFACE (MEGAFACE) F475, MEGAFACE (MEGAFACE) F479, MEGAFACE (MEGAFACE) F482, MEGAFACE (MEGAFACE) F554, MEGAFACE (MEGAFACE) F780, RS-72-K (the above is Dickson ( DIC) company manufacturing), Fluorad FC430, Fluorad FC431, Fluorad FC171, Novec FC4430, Novec FC4432 (the above are manufactured by 3M Company of Japan), Surflon S-382, Surflon SC-101, Surflon SC-103, Surflon SC-104, Surflon SC-105, Surflon SC-1068, Surflon SC-381, Surflon SC-383, Surflon S-393, Surflon KH-40 ( The above are manufactured by Asahi Glass Co., Ltd.), PF636, PF656, PF6320, PF6520, PF7002 (the above are manufactured by OMNOVA).

(Character) The surfactant is preferably liquid at 25°C and 1 atm. Since the surfactant is liquid at 25°C and 1 atm, the solubility in the composition becomes good.

(viscosity) The viscosity eta of the surfactant is preferably 1 mPa·s or more, more preferably 10 mPa·s or more, further preferably 100 mPa·s or more, preferably 10,000 mPa·s or less, more preferably 5,000 mPa·s or less. . When the viscosity eta of the surfactant is within the above range, the dark current of the photoelectric conversion element can be effectively reduced.

Here, the viscosity eta is a value measured with a rheometer at a temperature of 25°C and a shear speed of 100 (1/s).

(molecular weight) The peak molecular weight Mp of the surfactant is preferably 100 or more, more preferably 1,000 or more, preferably 10,000 or less, more preferably 5,000 or less. When the peak molecular weight Mp of the surfactant is within the above range, the dark current of the photoelectric conversion element can be effectively reduced.

Here, the peak molecular weight Mp of the surfactant is a value measured by gel permeation chromatography (Gel Permeation Chromatography, GPC). The peak molecular weight Mp may be the peak top value in GPC chromatography measured under the following measurement conditions.

As the mobile phase of GPC, o-dichlorobenzene was used and flowed at a flow rate of 1.0 mL/min. As the pipe column, Shodex KD-806M manufactured by Showa Denko Co., Ltd. was used, and as the guard column, Shodex KD-G manufactured by Showa Denko Co., Ltd. was used.

As detectors, a UV-vis detector (manufactured by Shimadzu Corporation, SPD-M20A) and a differential refractive index detector (manufactured by Shimadzu Corporation, RID-10A) were used.

The compound (polymer) to be measured was mixed with 1-chloronaphthalene as a solvent at a concentration of 0.05% by mass, and stirred at 80° C. for 2 hours to dissolve the mixture to prepare a solution.

The obtained solution was injected into the measurement device (GPC) in an amount of 10 μL as a sample, and the peak molecular weight (Mp) was measured.

(fluorine content) When the surfactant is a fluorine-based surfactant, the fluorine content of the surfactant is preferably 1 mass% or more when the solid content excluding the solvent in the fluorine-based surfactant is 100 mass%. Preferably, it is 5 mass % or more, More preferably, it is 50 mass % or less, More preferably, it is 30 mass % or less. When the fluorine content of the surfactant is within the above range, the dark current of the photoelectric conversion element can be effectively reduced. When the fluorine content of the surfactant is less than the upper limit, the water repellency of the film (active film) obtained from the composition decreases, and the aqueous coating liquid can be easily coated on the film.

The fluorine content in the surfactant can be measured by combustion ion chromatography or the like.

(Content ratio of surfactant) The content ratio of the surfactant in the composition is preferably 0.01 mass% or more, more preferably 0.1 mass% or more, preferably 1.0 mass% or less, and more preferably 0.5 when the total mass of the solvent is 100 mass%. mass% or less.

The content ratio of the surfactant in the composition is preferably 0.1 mass% or more, more preferably 1 mass% or more, when the total mass of the n-type semiconductor, p-type semiconductor and surfactant is 100 mass%. It is 10 mass % or less, more preferably, it is 5 mass % or less.

When the content ratio of the surfactant in the composition is within the above range, the dark current of the photoelectric conversion element can be effectively reduced.

[2.2.p-type semiconductor] The p-type semiconductor contained in the composition of this embodiment may be one type alone or a combination of two or more types.

The p-type semiconductor may be a low molecular compound or a polymer compound, preferably a polymer compound, and more preferably a π-conjugated polymer compound.

Examples of p-type semiconductors that are polymer compounds include polyvinylcarbazole and its derivatives, polysilane and its derivatives, and polysiloxane derivatives containing an aromatic amine structure in the side chain or main chain. , polyaniline and its derivatives, polythiophene and its derivatives, polypyrrole and its derivatives, polyphenylene vinylene and its derivatives, polythienylene vinylene and its derivatives, polyfluorene and its derivatives .

(Donor/Receptor Structure) The p-type semiconductor is preferably a polymer compound having a donor/acceptor structure. The donor/receptor structure includes donor building blocks and receptor building blocks. The donor constituent unit is a constituent unit with an excess of π electrons, and the acceptor constituent unit is a constituent unit with a deficiency of π electrons.

The structural units that can constitute a polymer compound having a donor/receptor structure also include structural units in which a donor structural unit and a receptor structural unit are directly bonded, and a donor structural unit and a receptor structural unit are connected through any suitable A structural unit formed by bonding spacers (bases or structural units).

From the viewpoint of effectively reducing dark current, the p-type semiconductor preferably contains a component selected from the group consisting of a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II). A polymer compound with more than one building block.

(Constituting unit represented by formula (I))

[Chemical 8]

In formula (I), Ar ¹ and Ar ² each independently represent a trivalent aromatic heterocyclic group which may have a substituent, and Z represents any one of the following formulas (Z-1) to formula (Z-7) the basis represented.

[Chemical 9]

In Formula (Z-1) to Formula (Z-7), R represents: a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, cycloalkenyl group which may have a substituent, alkynyl which may have a substituent, cycloalkynyl which may have a substituent, aryl which may have a substituent, alkoxy which may have a substituent, cycloalkoxy which may have a substituent group, an aryloxy group which may have a substituent, an alkylthio group which may have a substituent, a cycloalkylthio group which may have a substituent, an arylthio group which may have a substituent, a monovalent heterocyclic group which may have a substituent, Substituted amino group which may have a substituent, imine residue which may have a substituent, amide group which may have a substituent, amide group which may have a substituent, substituted oxycarbonyl group which may have a substituent, cyano group , nitro group, a group represented by -C(=O)-R ^c , or a group represented by -SO ₂ -R ^d , R ^c and R ^d each independently represent: a hydrogen atom, an alkyl group which may have a substituent , a cycloalkyl group that may have a substituent, an aryl group that may have a substituent, an alkoxy group that may have a substituent, a cycloalkoxy group that may have a substituent, an aryloxy group that may have a substituent, or a substituted Monovalent heterocyclic group of base. In Formula (Z-1) to Formula (Z-7), when there are two R's, the two R's may be the same or different. Z is preferably a group represented by formula (Z-4) or formula (Z-5).

R in formula (Z-1) to formula (Z-7) is preferably a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, more preferably a hydrogen atom or an alkyl group, and further preferably a hydrogen atom or a number of carbon atoms. An alkyl group having 1 to 40 carbon atoms is more preferably a hydrogen atom or an alkyl group having 1 to 30 carbon atoms, particularly preferably a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. These groups may have substituents. When there are multiple R's, the multiple R's may be the same or different from each other.

The structural unit represented by formula (I) is preferably a structural unit represented by the following formula (I-1).

[Chemical 10]

In formula (I-1), Z represents the same meaning as described above.

Examples of the structural unit represented by formula (I-1) include structural units represented by the following formula (501) to formula (505).

[Chemical 11]

In the formula (501) to formula (505), R represents the same meaning as described above. When there are two R's, the two R's may be the same or different from each other.

The structural unit represented by formula (I) is preferably a group represented by formula (501).

(Constituting unit represented by formula (II))

[Chemical 12]

In the formula (II), Ar ³ represents a divalent aromatic heterocyclic group. The number of carbon atoms of the divalent aromatic heterocyclic group represented by Ar ³ is usually 2 to 60, preferably 4 to 60, and more preferably 4 to 20. The divalent aromatic heterocyclic group represented by Ar ³ may have a substituent.

The structural unit represented by formula (II) is preferably a structural unit represented by any one of the following formulas (II-1) to formula (II-8).

[Chemical 13]

In formula (II-1) to formula (II-8), X ¹ and X ² independently represent a sulfur atom or an oxygen atom, and Z ¹ and Z ² each independently represent a group represented by =C(R)- or Nitrogen atom, R has the same definition as in formula (Z-1) to formula (Z-7). Multiple R's may be the same or different from each other.

In formula (II-6), the two R's are preferably each independently a hydrogen atom, an alkyl group or a halogen atom, more preferably both are a hydrogen atom or a halogen atom, and still more preferably both are a halogen atom.

From the viewpoint of the availability of the raw material compound, it is preferable that X ¹ and X ² in Formula (II-1) to Formula (II-8) are both sulfur atoms.

Examples of the divalent aromatic heterocyclic group represented by Ar ³ include groups represented by the following formulas (101) to (190). These groups may have substituents.

[Chemical 14]

[Chemical 15]

[Chemical 16]

[Chemical 17]

In Formula (101) to Formula (190), R has the same meaning as described above. When there are multiple R's, the multiple R's may be the same or different from each other.

The p-type semiconductor may have an aryl group in addition to the structural unit represented by the formula (I) and/or the structural unit represented by the formula (II). Aryl refers to a divalent aromatic carbocyclic group. The aryl group may have a substituent.

The number of carbon atoms in the part other than the substituent in the aryl group is usually 6 to 60, preferably 6 to 20. The number of carbon atoms of the aryl group including substituents is usually 6 to 100.

Examples of the aryl group include phenylene, naphthalene-diyl, anthracene-diyl, biphenyl-diyl, terphenyl-diyl, fluorene-diyl and benzofluorene-diyl.

When the p-type semiconductor is a polymer compound containing a structural unit represented by formula (I) and/or a structural unit represented by formula (II), the structural unit represented by formula (I) and the structural unit represented by formula (II) The total amount of the structural units shown is usually 20 mol% to 100 mol%. In order to improve the charge transport properties of the p-type semiconductor, it is preferably 40 mol% to 100 mol%, more preferably 50 mol%. Mol%~100mol%. Here, the amount of all structural units contained in the polymer compound is set to 100 mol%.

Preferable specific examples of p-type semiconductors include the following polymer compounds.

[Chemical 18]

(content of p-type semiconductor) The content of the p-type semiconductor in the composition can be set to any appropriate content depending on the required thickness of the functional layer (active layer), desired characteristics, and the like. For example, the content of the p-type semiconductor in the composition is preferably 0.1 mass% or more, more preferably 1 mass% or more, preferably 20 mass% or less, and more preferably 10 mass% when the composition is 100 mass%. %the following.

[2.3.n-type semiconductor] The n-type semiconductor contained in the composition of this embodiment may be one type alone or a combination of two or more types.

The n-type semiconductor can be a low molecular compound or a high molecular compound. Examples of n-type semiconductors include: oxadiazole derivatives, anthraquinonedimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, and tetracyanoanthracene Quinodimethane and its derivatives, fluorenone derivatives, diphenyldicyanoethylene and its derivatives, diphenoquinone derivatives, metal complexes of 8-hydroxyquinoline and its derivatives, C ₆₀ Fuller Fullerenes such as ene and their derivatives, that is, fullerene derivatives (hereinafter, sometimes referred to as fullerene compounds) and 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline Phenanthrene derivatives.

The n-type semiconductor may be a fullerene such as C ₆₀ fullerene and its derivatives, that is, a fullerene derivative, or may be a non-fullerene compound. Hereinafter, fullerene and fullerene derivatives may be referred to as fullerene compounds. Non-fullerene compounds refer to compounds other than fullerene and fullerene derivatives.

(fullerene compound) In one embodiment, the n-type semiconductor contained in the composition is preferably one or more types selected from the group consisting of fullerene and fullerene derivatives, and more preferably is a fullerene derivative.

Examples of fullerenes include C ₆₀ fullerene, C ₇₀ fullerene, C ₇₆ fullerene, C ₇₈ fullerene and C ₈₄ fullerene. Examples of fullerene derivatives include these fullerene derivatives. Fullerene derivatives refer to compounds in which at least part of fullerene has been modified.

Examples of fullerene derivatives include compounds represented by the following formulas.

[Chemical 19]

In the formula, R ^a represents an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a group having an ester structure, and these groups may also have substituents. There are multiple R ^a's that may be the same or different from each other. R ^b represents an alkyl group, a cycloalkyl group or an aryl group, and these groups may have substituents. There are a plurality of R ^b's which may be the same or different from each other.

Examples of the group having an ester structure represented by R ^a include groups represented by the following formulas.

[Chemistry 20]

In the formula, u1 represents an integer from 1 to 6. u2 represents an integer from 0 to 6. R ^e represents an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, and these groups may have substituents.

Examples of C ₆₀ fullerene derivatives include the following compounds.

[Chemistry 21]

Examples of C ₇₀ fullerene derivatives include the following compounds.

[Chemistry 22]

Specific examples of fullerene derivatives include [6,6]-phenyl-C61 butyric acid methyl ester (C ₆₀ PCBM, [6,6]-Phenyl C61 butyric acid methyl ester), [6,6] ]-Phenyl-C71 butyric acid methyl ester (C ₇₀ PCBM, [6,6]-Phenyl C71 butyric acid methyl ester), [6,6]-phenyl-C85 butyric acid methyl ester (C ₈₄ PCBM, [6 ,6]-Phenyl C85 butyric acid methyl ester), and [6,6]-Thienyl-C61 butyric acid methyl ester ([6,6]-Thienyl C61 butyric acid methyl ester).

(non-fullerene compounds) In another embodiment, the n-type semiconductor contained in the composition is preferably a non-fullerene compound. Various compounds are known as non-fullerene compounds, and any suitable conventionally known non-fullerene compound can be used as the n-type semiconductor in this embodiment.

In one embodiment, the n-type semiconductor contained in the composition is preferably a compound containing a perylene tetracarboxylic acid diimide structure. Examples of compounds containing a perylenetetracarboxylic acid diimide structure as non-fullerene compounds include compounds represented by the following formulas.

[Chemistry 23]

[Chemistry 24]

[Chemical 25]

[Chemical 26]

In the formula, R is as defined above. Multiple R's may be the same or different from each other.

In one embodiment, the n-type semiconductor is preferably a compound represented by the following formula (V). The compound represented by the following formula (V) is a non-fullerene compound containing a perylenetetracarboxylic acid diimide structure.

[Chemical 27]

In the formula (V), R ¹ represents a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, or a cycloalkyl which may have a substituent. An oxygen group, an aryl group which may have a substituent, or a monovalent aromatic heterocyclic group which may have a substituent. The plural R ^1's may be the same or different from each other.

It is preferable that each of the plurality of R ¹ 's present is independently an alkyl group which may have a substituent.

R ² represents a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, a cycloalkoxy group which may have a substituent, or a cycloalkyl group which may have a substituent. An aryl group, or a monovalent aromatic heterocyclic group which may have a substituent. The plurality of R ² may be the same or different.

In another embodiment, the n-type semiconductor is preferably a compound represented by the following formula (VI). A ¹ -B ¹⁰ -A ² (VI)

In the formula (VI), A ¹ and A ² each independently represent an electron-withdrawing group, and B ¹⁰ represents a group containing a π conjugated system.

Examples of the electron-withdrawing group of A ¹ and A ² include groups represented by -CH=C(-CN) ₂ and groups represented by the following formulas (a-1) to formula (a-9).

[Chemical 28]

In formula (a-1) to formula (a-7), T represents a carbocyclic ring which may have a substituent, or a heterocyclic ring which may have a substituent. Carbocyclic and heterocyclic rings may be single rings or condensed rings. When the rings have multiple substituents, the multiple substituents may be the same or different.

Examples of the carbocyclic ring that may have a substituent for T include an aromatic carbocyclic ring, and an aromatic carbocyclic ring is preferred. Specific examples of the carbocyclic ring which may have a substituent for T include: benzene ring, naphthalene ring, anthracene ring, condensed tetraphenyl ring, condensed pentaphenyl ring, pyrene ring and phenanthrene ring, preferably benzene ring, naphthalene ring and The phenanthrene ring is more preferably a benzene ring and a naphthalene ring, and further preferably a benzene ring. These rings may have substituents.

Examples of the heterocyclic ring that may have a substituent for T include an aromatic heterocyclic ring, and an aromatic heterocyclic ring is preferred. Specific examples of the heterocyclic ring that may have a substituent for T include a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, an oxazole ring, a thiazole ring, and a thiophene ring. The thiophene ring is preferably a thiophene ring, a pyridine ring, a pyrazine ring, a thiazole ring and a thienothiophene ring, and more preferably a thiophene ring. These rings may have substituents.

Examples of the substituent that the carbocyclic ring or heterocyclic ring of T may have include a halogen atom, an alkyl group, an alkoxy group, an aryl group and a monovalent heterocyclic group, preferably a fluorine atom and/or a carbon number of 1 to 1 6 alkyl.

_X ⁴ , _X ^{5 and} the basis represented.

X ⁷ represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, an aryl group which may have a substituent, or a monovalent heterocyclic group.

R ^a1 , R ^a2 , R ^a3 , R ^a4 and R ^a5 each independently represent a hydrogen atom, an alkyl group which may have a substituent, a halogen atom, an alkoxy group which may have a substituent, an aryl group which may have a substituent, or a The valent heterocyclic group is preferably an alkyl group which may have a substituent or an aryl group which may have a substituent.

[Chemical 29]

In Formula (a-8) and Formula (a-9), R ^a6 and R ^a7 each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, or a cycloalkyl group which may have a substituent. The alkoxy group of the base, the cycloalkoxy group that may have a substituent, the monovalent aromatic carbocyclic group that may have a substituent, or the monovalent aromatic heterocyclic group that may have a substituent, there are multiple R ^a6 and R ^a7 can be the same or different.

Preferred electron-withdrawing groups for A ¹ and A ² are the following formulas (a-1-1) to formula (a-1-4), formula (a-6-1) and formula (a-7- The group represented by any one of 1) is more preferably a group represented by formula (a-1-1). Here, the plurality of R ^a10 each independently represents a hydrogen atom or a substituent, and preferably represents a hydrogen atom, a halogen atom, a cyano group or an alkyl group which may have a substituent. R ^a3 , R ^a4 and R ^a5 each independently have the same meaning as described above, preferably each independently represents an alkyl group which may have a substituent or an aryl group which may have a substituent.

[Chemical 30]

Examples of the group containing a π conjugated system in B ¹⁰ include a group represented by -(S ¹ ) _n1 -B ¹¹ -(S ² ) _n2 - in the compound represented by formula (VII) to be described later.

In this embodiment, the n-type semiconductor is preferably a compound represented by the following formula (VII). A ¹ -(S ¹ ) _n1 -B ¹¹ -(S ² ) _n2 -A ² (VII)

In formula (VII), A ¹ and A ² each independently represent an electron-withdrawing group. Examples and preferred examples of A ¹ and A ² are the same as those described for A ¹ and A ² in the formula (VI).

S ¹ and S ² each independently represent a divalent carbocyclic group which may have a substituent, a divalent heterocyclic group which may have a substituent, or a group represented by -C(R ^s1 )=C(R ^s2 )- (herein where, R ^s1 and R ^s2 each independently represent a hydrogen atom, or a substituent (preferably a hydrogen atom, a halogen atom, an alkyl group that may have a substituent, or a monovalent heterocyclic group that may have a substituent)), or The base represented by -C≡C-.

The divalent carbocyclic group which may have a substituent and the divalent heterocyclic group which may have a substituent represented by ^S1 and ^S2 may be a condensed ring. When a divalent carbocyclic group or a divalent heterocyclic group has multiple substituents, the plurality of substituents may be the same or different.

In formula (VII), n1 and n2 each independently represent an integer above 0, preferably each independently represents 0 or 1, and more preferably simultaneously represents 0 or 1.

Examples of the divalent carbocyclic group include divalent aromatic carbocyclic groups. Examples of the divalent heterocyclic group include a divalent aromatic heterocyclic group. When the divalent aromatic carbocyclic group or the divalent aromatic heterocyclic group is a condensed ring, all of the rings constituting the condensed ring may be aromatic condensed rings, or only a part may be aromatic. Condensation ring.

Examples of S ¹ and S ² include those represented by any one of the formulas (101) to (190) listed as examples of the divalent aromatic heterocyclic group represented by Ar ³ described above. groups, and groups in which hydrogen atoms in these groups are substituted by substituents.

It is preferred that S ¹ and S ² independently represent a group represented by the following formula (s-1) or formula (s-2).

[Chemical 31]

In formula (s-1) and formula (s-2), X ³ represents an oxygen atom or a sulfur atom. R ^a10 is as defined above.

S ¹ and S ² are preferably each independently a group represented by formula (142), formula (148), or formula (184), or a group in which hydrogen atoms in these groups are substituted by substituents, and more preferably Preferably, the group is a group represented by the formula (142) or the formula (184), or a group in which one hydrogen atom in the group represented by the formula (184) is substituted by an alkoxy group.

B ¹¹ is a condensed ring group of two or more structures selected from the group consisting of a carbocyclic structure and a heterocyclic structure, and represents a condensed ring group that does not contain an ortho-para condensed structure and may have a substituent.

The condensed ring group represented by B ¹¹ may include a structure in which two or more identical structures are condensed.

When the condensed ring group represented by B ¹¹ has a plurality of substituents, the plurality of substituents may be the same or different.

Examples of the carbocyclic structure that can constitute the condensed cyclic group represented by B ¹¹ include a ring structure represented by the following formula (Cy1) or formula (Cy2).

[Chemical 32]

Examples of the heterocyclic structure that can constitute the condensed cyclic group represented by B ¹¹ include ring structures represented by any one of the following formulas (Cy3) to formula (Cy10).

[Chemical 33]

In the formula (VII), B ¹¹ is preferably a fused ring group of two or more structures selected from the group consisting of the structures represented by the formula (Cy1) to the formula (Cy10), and does not contain adjacent - A condensed ring group that has a per-position condensation structure and may have a substituent. B ¹¹ may include a structure in which two or more identical structures among the structures represented by formula (Cy1) to formula (Cy10) are condensed.

B ¹¹ is more preferably a fused ring group of two or more structures selected from the group consisting of structures represented by formula (Cy1) to formula (Cy6) and formula (Cy8), and does not contain an ortho-position. A condensed ring group that has a condensed structure and may have a substituent.

The substituent that the condensed ring group of B ¹¹ may have is preferably an alkyl group that may have a substituent, an aryl group that may have a substituent, an alkoxy group that may have a substituent, and a monovalent heterocyclic group that may have a substituent. . The aryl group that the condensed cyclic group represented by B ¹¹ may have may be substituted with an alkyl group, for example.

Examples of the condensed cyclic group of B ¹¹ include groups represented by the following formulas (b-1) to formula (b-14), and groups in which the hydrogen atoms in these groups are substituted (preferably they may have substituted groups). alkyl group, an aryl group that may have a substituent, an alkoxy group that may have a substituent, or a monovalent heterocyclic group that may have a substituent) substituted.

The condensed ring group of B ¹¹ is preferably a group represented by the following formula (b-2) or formula (b-3), or a group in which the hydrogen atom in these groups is substituted (preferably a group that may have a substituent) an alkyl group, an aryl group which may have a substituent, an alkoxy group which may have a substituent, or a monovalent heterocyclic group which may have a substituent) substituted, more preferably the following formula (b-2) or formula The basis represented by (b-3).

[Chemical 34]

[Chemical 35]

In formula (b-1) to formula (b-14), R ^a10 is as defined above. In formulas (b-1) to formula (b-14), it is preferable that a plurality of R ^a10 present are each independently an alkyl group which may have a substituent, or an aryl group which may have a substituent.

Examples of compounds represented by formula (VI) or formula (VII) include compounds represented by the following formulas.

[Chemical 36]

[Chemical 37]

In the formula, R is as defined above, and X represents a hydrogen atom, a halogen atom, a cyano group or an alkyl group which may have a substituent. In the formula, R is preferably a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or an alkoxy group which may have a substituent.

The composition may contain only a non-fullerene compound as an n-type semiconductor, may contain only a fullerene compound, or may contain a combination of a non-fullerene compound and a fullerene compound.

Suitable specific examples of the n-type semiconductor contained in the composition include compounds represented by the following formula.

[Chemical 38]

(Content of n-type semiconductor) The content of the n-type semiconductor in the composition can be set to any appropriate content depending on the required thickness of the functional layer (active layer), desired characteristics, and the like. For example, when the composition is 100 mass%, the content of the n-type semiconductor in the composition is preferably 0.1 mass% or more, more preferably 1 mass% or more, preferably 20 mass% or less, and more preferably 10 mass% %the following.

(The mass ratio of p-type semiconductor to n-type semiconductor (p-type semiconductor/n-type semiconductor)) The mass ratio of p-type semiconductor to n-type semiconductor (p-type semiconductor/n-type semiconductor) in the composition is preferably 1/9 or more, more preferably 1/5 or more, further preferably 1/3 or more, and still more preferably It is 9/1 or less, more preferably 5/1 or less, still more preferably 3/1 or less. Here, when the composition contains a plurality of types of p-type semiconductors, the mass ratio is a ratio relative to the total mass of the p-type semiconductors, and when the composition contains a plurality of types of n-type semiconductors, the mass ratio is a ratio relative to the total mass of the n-type semiconductors.

[2.4. Solvent] The solvent contained in the composition of this embodiment may be one type alone or a combination of two or more types.

The composition of this embodiment may also contain aromatic hydrocarbons as a solvent, and preferably contains aromatic hydrocarbons. The aromatic hydrocarbon may have a substituent. As the aromatic hydrocarbon, a compound capable of dissolving the p-type semiconductor described above is particularly preferred.

Examples of aromatic hydrocarbons that can be used as solvents include toluene, xylene (such as o-xylene, m-xylene, and p-xylene), trimethylbenzene (such as mesitylene, 1,2,4-trimethylbenzene, Methylbenzene (pseudocumene)), butylbenzene (such as n-butylbenzene, 2nd butylbenzene, 3rd butylbenzene), methylnaphthalene (such as 1-methylnaphthalene), 1,2,3 , 4-tetralin (tetralin), indene, 1-chloronaphthalene, chlorobenzene and dichlorobenzene (1,2-dichlorobenzene).

The solvent may contain only one aromatic hydrocarbon, or may contain two or more aromatic hydrocarbons.

The aromatic hydrocarbons that can constitute the solvent are preferably selected from toluene, o-xylene, m-xylene, p-xylene, mesitylene, 1,2,4-trimethylbenzene, n-butylbenzene, and 2-butylbenzene. One or more of the group consisting of benzene, tert-butylbenzene, methylnaphthalene, tetrahydronaphthalene, 1-chloronaphthalene, chlorobenzene and dichlorobenzene (1,2-dichlorobenzene).

The content of the aromatic hydrocarbon solvent in the solvent is preferably 80 mass% or more, more preferably 90 mass% or more, and usually 100 mass% or less when the total mass of the solvent is 100 mass%.

The composition of this embodiment may include an alkyl halide as a solvent. Examples of the halogenated alkyl group that can be used as a solvent include chloroform.

In addition to using the above-mentioned solvent, the composition of this embodiment may also use in combination another solvent selected especially from the viewpoint of improving the solubility of the n-type semiconductor.

In this embodiment, examples of other solvents include aromatic carbonyl compounds, aromatic ester compounds, and nitrogen-containing heterocyclic compounds. The composition of this embodiment may also include one or two or more compounds selected from the group consisting of aromatic carbonyl compounds, aromatic ester compounds, and nitrogen-containing heterocyclic compounds as solvents.

Examples of the aromatic carbonyl compound include acetophenone, phenylacetone, phenybutanone, cyclohexyl phenyl ketone, and benzophenone, and these compounds may have a substituent.

Examples of the aromatic ester compound include methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, isopropyl benzoate, benzyl benzoate, cyclohexyl benzoate, and benzoate. esters, these compounds may also have substituents.

Examples of nitrogen-containing heterocyclic compounds include pyridine, quinoline, quinoxaline, 1,2,3,4-tetrahydroquinoline, pyrimidine, pyrazine and quinazoline. These nitrogen-containing heterocyclic compounds The compound may also have a substituent.

The nitrogen-containing heterocyclic compound may also have a substituent directly bonded to the ring structure. Examples of substituents that the ring structure of the nitrogen-containing heterocyclic compound may have include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a halogen atom, and an alkylthio group.

When the total mass of the composition is 100% by mass, from the viewpoint of further improving the solubility of the p-type semiconductor and the n-type semiconductor, the total mass of the solvent contained in the composition of this embodiment is preferably 90%. Mass % or more, more preferably 92 mass % or more, still more preferably 95 mass % or more, from the viewpoint of further increasing the concentration of p-type semiconductor and n-type semiconductor in the composition and making it easier to form a layer having a certain thickness or more. Preferably, it is 99.9 mass % or less.

[2.5. Optional ingredients] In addition to the p-type semiconductor, n-type semiconductor, surfactant, and solvent, the composition of this embodiment may also contain any component within the limits that do not impair the purpose and effect of the present invention. Examples of optional components include ultraviolet absorbers, antioxidants, sensitizers for sensitizing the function of generating charges by absorbed light, and photostabilizers for increasing stability from ultraviolet rays.

The total content of arbitrary components in the composition is preferably 10 mass% or less, more preferably 5 mass% or less, and is usually 0 mass% or more, and may be 0 mass%.

[2.6. Properties of components, etc.] In the composition, p-type semiconductor and n-type semiconductor can be dissolved or dispersed. In the composition, it is preferable that the p-type semiconductor and the n-type semiconductor are at least partially dissolved.

The total concentration of the p-type semiconductor and the n-type semiconductor in the composition of this embodiment can be set to any appropriate concentration depending on the required thickness of the functional layer (active layer), desired characteristics, and the like. The total concentration of p-type semiconductor and n-type semiconductor is preferably 0.01 mass% or more, more preferably 0.1 mass% or more, preferably 10 mass% or less, more preferably 5 mass% or less, still more preferably 0.01 mass% or more. 20 mass % or less, more preferably 0.01 mass % or more and 10 mass % or less, more preferably 0.01 mass % or more and 5 mass % or less, particularly preferably 0.1 mass % or more and 5 mass % or less.

[2.7. Manufacturing method of composition] The composition can be produced by conventionally known methods. The solvent, p-type semiconductor, n-type semiconductor and surfactant may be heated to a temperature lower than the boiling point of the solvent and mixed.

After mixing the solvent with the p-type semiconductor, the n-type semiconductor and the surfactant, the obtained mixture is filtered using a filter, and the obtained filtrate is used as the composition. As the filter, for example, a filter made of a fluororesin such as polytetrafluoroethylene (PTFE) can be used.

[2.8.Use of composition] The composition can be suitably used as an ink for forming a film including a p-type semiconductor, an n-type semiconductor and a surfactant by a coating method.

In this specification, "ink" refers to a liquid substance used in a coating method and is not limited to a colored liquid. In addition, the "coating method" includes a method of forming a film (layer) using a liquid substance. Examples of coating methods include slot die coating, slit coating, blade coating, casting, microgravure coating, gravure coating, rod coating, roll coating, and line coating. Rod coating method, dip coating method, spray coating method, screen printing method, gravure printing method, flexographic printing method, offset printing method, inkjet coating method, dispenser printing method, nozzle coating method and capillary tube coating method.

[3.Membrane] A film according to one embodiment of the present invention contains a p-type semiconductor, an n-type semiconductor, and a surfactant. This film can be suitably used as an active layer contained in a photoelectric conversion element.

Examples and preferred examples of p-type semiconductors, n-type semiconductors, and surfactants contained in the film are respectively the same as examples and preferred examples of p-type semiconductors, n-type semiconductors, and surfactants that can be included in the composition. The examples are the same.

The content of the p-type semiconductor in the film of this embodiment can be set to any appropriate content depending on desired characteristics and the like. For example, the content of the p-type semiconductor in the film is preferably 1% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, preferably 99% by mass or less, and more preferably 90% by mass or less. More preferably, it is 80 mass % or less.

The content of the n-type semiconductor in the film of this embodiment can be set to any appropriate content depending on desired characteristics and the like. For example, the content of the n-type semiconductor in the film is preferably 1% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, preferably 99% by mass or less, and more preferably 90% by mass or less. More preferably, it is 80 mass % or less.

The mass ratio of p-type semiconductor to n-type semiconductor in the film of this embodiment (p-type semiconductor/n-type semiconductor) is generally the same as the mass ratio of p-type semiconductor to n-type semiconductor in the composition used to produce the film. .

The content ratio of the surfactant in the film of this embodiment is preferably 0.1 mass% or more, more preferably 1 mass% or more when the total mass of the n-type semiconductor, p-type semiconductor and surfactant is 100 mass%. , preferably 10 mass% or less, more preferably 5 mass% or less.

It is preferable that the film of this embodiment does not contain a solvent substantially. The content of the solvent in the film of this embodiment is preferably 1 mass% or less, more preferably 0.1 mass% or less, and is usually 0 mass% or more, and may be 0 mass%.

The film of this embodiment can be produced by any method. For example, the film of the present embodiment can be produced by a production method that includes the steps (i) of applying the composition to a coating object to obtain a coating film, and from the obtained coating film. Step (ii) of removing solvent from the membrane.

(step (i)) In step (i), as a method of applying the composition to the object to be coated, any of the conventionally known coating methods described above can be used.

In step (i), the composition is coated on any coating object. In the manufacturing step of the photoelectric conversion element, for example, the composition can be coated on functional layers that the photoelectric conversion element can include, such as electrodes (anode or cathode), electron transport layers or hole transport layers.

(step (ii)) In step (ii), any suitable method can be used as a method for removing the solvent from the coating film of the composition formed in step (i). Examples of methods for removing solvents include drying methods such as hot air drying, infrared heating drying, flash lamp annealing drying, and reduced pressure drying.

[4. Organic photoelectric conversion element] [4.1. Structure of photoelectric conversion element] The photoelectric conversion element of this embodiment includes a first electrode, a second electrode, and an active layer provided between the first electrode and the second electrode, and the active layer is the film already described. Hereinafter, a structural example of the photoelectric conversion element of this embodiment will be specifically described with reference to the drawings.

FIG. 1 is a diagram schematically showing a structural example of a photoelectric conversion element.

As shown in FIG. 1 , the photoelectric conversion element 10 is provided on the supporting substrate 11 . The photoelectric conversion element 10 includes a first electrode 12 provided in contact with the support substrate 11 , a first intermediate layer 13 provided in contact with the first electrode 12 , and a first intermediate layer 13 provided in contact with the first intermediate layer 13 . The active layer 14 is provided in such a manner as to be in contact with the active layer 14 , the second intermediate layer 15 is provided in such a manner as to be in contact with the active layer 14 , and the second electrode 16 is provided in such a manner as to be in contact with the second intermediate layer 15 . In the above-mentioned structural example, the sealing member 17 is further provided in contact with the second electrode 16 . In this embodiment, both the first intermediate layer 13 and the second intermediate layer 15 are provided, but only one of the first intermediate layer 13 and the second intermediate layer 15 may be provided. For example, the first intermediate layer 13 may not be provided. For example, the second intermediate layer 15 may not be provided.

Hereinafter, the structural elements that can be included in the photoelectric conversion element of this embodiment will be described in detail.

(Substrate) Photoelectric conversion elements are usually formed on a substrate (support substrate). In addition, it may be further sealed by a substrate (sealing substrate). One of a pair of electrodes including a first electrode and a second electrode is usually formed on the substrate. The material of the substrate is not particularly limited as long as it does not undergo chemical change when forming a layer containing an organic compound.

Examples of the material of the substrate include glass, plastic, polymer film, and silicon. When an opaque substrate is used, it is preferable that the electrode on the opposite side to the electrode provided on the opaque substrate side (in other words, the electrode on the side far from the opaque substrate) is a transparent or semi-transparent electrode.

(electrode) The photoelectric conversion element includes a first electrode and a second electrode as a pair of electrodes. In order to allow light to enter, at least one of the first electrode and the second electrode is preferably a transparent or translucent electrode.

Examples of materials for transparent or translucent electrodes include conductive metal oxide films and translucent metal thin films. Specifically, indium oxide, zinc oxide, tin oxide, and composites of these include indium tin oxide (Indium Tin Oxide, ITO), indium zinc oxide (Indium Zinc Oxide, IZO), Neisser ( NESA) and other conductive materials, gold, platinum, silver, copper. Preferable materials for transparent or translucent electrodes are ITO, IZO, and tin oxide. In addition, as the electrode, a transparent conductive film using an organic compound such as polyaniline and its derivatives, polythiophene and its derivatives as a material can be used. The transparent or translucent electrode may be the first electrode or the second electrode.

If one of the pair of electrodes is transparent or translucent, the other electrode may be an electrode with low light transmittance. Examples of materials for electrodes with low light transmittance include metals and conductive polymers. Specific examples of materials for electrodes with low light transmittance include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, and europium. , ytterbium, ytterbium and other metals, and alloys of two or more of these, or one or more of these metals and selected from gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten and tin. Alloys of more than one metal in the group, graphite, graphite intercalation compounds, polyaniline and its derivatives, polythiophene and its derivatives. Examples of alloys include magnesium-silver alloys, magnesium-indium alloys, magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum alloys, lithium-magnesium alloys, lithium-indium alloys, and calcium-aluminum alloys.

(active layer) The photoelectric conversion element of this embodiment includes the film described above as an active layer. The active layer of this embodiment has a bulk heterojunction type structure.

In this embodiment, the thickness of the active layer is not particularly limited. For example, the thickness of the active layer can be set to any appropriate thickness in consideration of the balance between suppression of dark current and extraction of generated photocurrent. In particular, from the viewpoint of further reducing dark current, the thickness of the active layer is preferably 100 nm or more, more preferably 150 nm or more, and further preferably 200 nm or more. In addition, the thickness of the active layer is preferably 10 μm or less, more preferably 5 μm or less, further preferably 1 μm or less.

(middle layer) As shown in FIG. 1 , the photoelectric conversion element of this embodiment preferably includes a charge transport layer (electron transport layer, hole transport layer, electron injection layer) as a component for improving characteristics such as photoelectric conversion efficiency. , hole injection layer) and other intermediate layers (buffer layer).

Examples of materials used in the intermediate layer include metals such as calcium, inorganic oxide semiconductors such as molybdenum oxide and zinc oxide, and PEDOT (poly(3,4-ethylenedioxythiophene)) and PSS (poly(3,4-ethylenedioxythiophene)). 4-styrenesulfonate)) mixture (PEDOT: PSS).

The intermediate layer can be formed by any suitable formation method known in the art. The intermediate layer can be formed by a vacuum evaporation method or a coating method similar to the formation method of the active layer.

As shown in FIG. 1 , the photoelectric conversion element of this embodiment preferably includes an electron transport layer as a first intermediate layer between the first electrode and the active layer. The photoelectric conversion element of this embodiment may include a hole transport layer as a second intermediate layer between the second electrode and the active layer, or may not include a hole transport layer as the second intermediate layer.

In yet another embodiment, the photoelectric conversion element preferably includes an electron transport layer as a second intermediate layer between the second electrode and the active layer. In another embodiment, the photoelectric conversion element may include a hole transport layer as the first intermediate layer between the first electrode and the active layer, or may not include the hole transport layer as the first intermediate layer.

The electron transport layer has the function of transporting electrons from the active layer to the electrode. The hole transport layer has the function of transporting holes from the active layer to the electrode.

The electron transport layer provided in contact with the electrode is sometimes specifically called an electron injection layer. The electron transport layer (electron injection layer) provided in contact with the electrode has the function of promoting the injection of electrons into the electrode. The electron transport layer (electron injection layer) can be connected to the active layer.

The electron transport layer contains an electron transport material. Examples of electron-transporting materials include polyalkyleneimine and its derivatives, polymer compounds containing a fluorene structure, metals such as calcium, and metal oxides.

Examples of polyalkyleneimine and its derivatives include ethyleneimine, propyleneimine, butyleneimine, dimethylethyleneimine, and pentyleneimine by conventional methods. A kind of alkylene imine having 2 to 8 carbon atoms, especially alkylene imine having 2 to 4 carbon atoms, such as alkylene imine, hexylene imine, heptyl imine, and octyl imine. Or polymers obtained by polymerizing two or more types, and polymers obtained by reacting these with various compounds and chemically modifying them. As polyalkyleneimine and its derivatives, polyethyleneimine (PEI) and ethoxylated polyethyleneimine (PEIE) are preferred.

Examples of polymer compounds containing a fluorene structure include poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-ortho-2 ,7-(9,9'-dioctylfluorene)] (PFN) and PFN-P2.

Examples of metal oxides include zinc oxide, gallium-doped zinc oxide, aluminum-doped zinc oxide, titanium oxide, and niobium oxide. As the metal oxide, a metal oxide containing zinc is preferred, and zinc oxide is particularly preferred.

Examples of other electron transporting materials include poly(4-vinylphenol) and perylenediamide.

Sometimes the hole transport layer provided in contact with the electrode is specifically called a hole injection layer. The hole transport layer (hole injection layer) provided in contact with the electrode has the function of promoting the injection of holes generated in the active layer into the electrode.

The hole transport layer contains a hole transport material. Examples of hole-transporting materials include polythiophene and its derivatives, aromatic amine compounds, polymer compounds containing structural units having aromatic amine residues, CuSCN, CuI, NiO, and tungsten oxide (WO ₃ ) and molybdenum oxide (MoO ₃ ).

(Sealing component) The photoelectric conversion element of this embodiment further includes a sealing member, and is preferably a sealed body sealed by the sealing member. Any suitable conventionally known member may be used as the sealing member. Examples of the sealing member include a combination of a glass substrate as a substrate (sealing substrate) and a sealing material (adhesive) such as UV curable resin.

The sealing member may also be a sealing layer having a layer structure of more than one layer. Examples of the layer constituting the sealing layer include a gas barrier layer and a gas barrier film.

The sealing layer is preferably formed of a material that has a property of blocking moisture (water vapor barrier property) or a property of blocking oxygen (oxygen barrier property). Examples of suitable materials for the sealing layer include trifluorinated polyethylene, polyethylene trifluoride (PCTFE), polyimide, polycarbonate, polyethylene terephthalate, and grease. Organic materials such as cyclic polyolefin and ethylene-vinyl alcohol copolymer, inorganic materials such as silicon oxide, silicon nitride, alumina, diamond-like carbon, etc.

The sealing member is made of a material that can withstand heat treatment that can be generally performed when being incorporated into a device to which a photoelectric conversion element is applied, such as an application example described below.

In another embodiment, both or any one of the first intermediate layer 13 and the second intermediate layer 15 may not be provided.

[4.2. Manufacturing method of photoelectric conversion element] The photoelectric conversion element of this embodiment can be manufactured by any suitable manufacturing method known in the art. The photoelectric conversion element of this embodiment can be manufactured by combining steps suitable for the materials selected when forming the constituent elements.

Hereinafter, as an embodiment of the present invention, a method for manufacturing a photoelectric conversion element having a structure in which a substrate (support substrate), a first electrode, a hole transport layer, an active layer, an electron transport layer, and a second electrode are sequentially connected to each other is described. instruction.

(Steps to prepare substrate) In this step, for example, a support substrate provided with a first electrode is prepared. In addition, a substrate provided with a conductive thin film made of the material of the electrode described above is obtained from the market, and if necessary, by patterning the conductive film to form a first electrode, a support substrate provided with the first electrode can be prepared. .

In the method of manufacturing the photoelectric conversion element of this embodiment, the method of forming the first electrode when forming the first electrode on the supporting substrate is not particularly limited. The first electrode can be formed by any suitable method known in the art such as vacuum evaporation, sputtering, ion plating, plating, coating, etc. The described materials are formed on the structure where the first electrode is to be formed (for example, on the supporting substrate, active layer, hole transport layer).

(Steps for forming hole transport layer) The method of manufacturing a photoelectric conversion element may include the step of forming a hole transport layer (hole injection layer) disposed between the active layer and the first electrode.

The formation method of the hole transport layer is not particularly limited. From the viewpoint of further simplifying the steps of forming the hole transport layer, it is preferable to form the hole transport layer by any suitable coating method known in the art. The hole transport layer can be formed, for example, by a coating method or a vacuum evaporation method using a coating liquid containing the material and solvent that can constitute the hole transport layer described above.

(Steps for forming active layer) In the method of manufacturing a photoelectric conversion element of this embodiment, an active layer is formed on the hole transport layer. The active layer can be formed by any suitable conventionally known formation steps. In this embodiment, the active layer can be produced by the coating method using the composition described above.

The active layer can be formed in the same manner as the "film" described above. In this embodiment, the active layer can be formed by the following steps, which include: coating a composition including a p-type semiconductor, an n-type semiconductor, a surfactant, and a solvent on the hole transport layer to form a coating film , and then the step of drying the coating film.

(Steps for forming electron transport layer) The method of manufacturing a photoelectric conversion element according to this embodiment may include the step of forming an electron transport layer (electron injection layer) provided in contact with the active layer.

The method of forming the electron transport layer is not particularly limited. From the viewpoint of further simplifying the steps of forming the electron transport layer, it is preferable to form the electron transport layer by any suitable vacuum evaporation method known in the art.

(Step of forming the second electrode) The formation method of the second electrode is not particularly limited. The second electrode can be formed from the material of the above-described electrode by any suitable method known in the art, such as coating method, vacuum evaporation method, sputtering method, ion plating method, plating method, etc. Through the above steps, the photoelectric conversion element of this embodiment is manufactured.

(Steps for forming the sealed body) When forming the sealing body, in this embodiment, any suitable conventionally known sealing material (adhesive) and substrate (sealing substrate) are used. Specifically, a sealing material such as a UV curable resin is applied to the support substrate so as to surround the periphery of the photoelectric conversion element to be produced, and the sealing material is attached without gaps, and then a sealing material suitable for the selection is used. A sealed body of the photoelectric conversion element can be obtained by sealing the photoelectric conversion element in the gap between the supporting substrate and the sealing substrate using methods such as sealing material or UV light irradiation.

[4.3. Application examples of photoelectric conversion elements] Examples of applications of the photoelectric conversion element of this embodiment include photodetection elements and solar cells. The photoelectric conversion element of this embodiment can generate photoelectromotive force between electrodes by irradiating light, and can operate as a solar cell. A solar cell module can also be made by gathering multiple photoelectric conversion elements.

The photoelectric conversion element of this embodiment can irradiate light from the transparent or translucent electrode side with a voltage (reverse bias voltage) applied between the electrodes, thereby allowing a photocurrent to flow, and can be used as a photodetection element (light sensor). detector) operation. In addition, it can also be used as an image sensor by gathering multiple light detection elements. The photoelectric conversion element of this embodiment can be particularly suitably used as a photodetection element.

The photoelectric conversion element of this embodiment can be suitably used as a light detection element in detection parts included in various electronic devices such as workstations, personal computers, portable information terminals, room entry and exit management systems, digital cameras, and medical equipment.

The photoelectric conversion element of this embodiment can be suitably applied to solid-state imaging devices such as X-ray imaging devices and complementary metal oxide semiconductor (CMOS) image sensors included in the exemplary electronic devices. A biological information authentication device that detects some predetermined characteristics of a living body such as an image detection unit (such as an image sensor such as an X-ray sensor), a fingerprint detection unit, a face detection unit, a vein detection unit, and an iris detection unit. In the detection part (such as a near-infrared sensor), the detection part of an optical biosensor such as a pulse oximeter, etc.

The photoelectric conversion element of this embodiment can be suitably applied to a time-of-flight (TOF) distance measuring device (TOF distance measuring device) as an image detection unit for a solid-state imaging device.

In a TOF type distance measuring device, the distance is measured by using a photoelectric conversion element to receive the reflected light obtained by reflecting the emitted light from the light source on the object to be measured. Specifically, the flight time before the irradiation light emitted from the light source is reflected by the measurement object and returns as reflected light is detected to determine the distance to the measurement object. There are direct TOF method and indirect TOF method in TOF type. The direct TOF method directly measures the difference between the time when light is irradiated from the light source and the time when the reflected light is received by the photoelectric conversion element. In the indirect TOF method, the distance is measured by converting the change in the amount of charge accumulation that depends on the flight time into a time change. Among the ranging principles used in the indirect TOF method to obtain time-of-flight through charge accumulation, there is a continuous wave (especially a sine wave) that obtains the time-of-flight based on the phase of the emitted light from the light source and the reflected light reflected by the object being measured. modulation method and pulse modulation method, but the photoelectric conversion element of this embodiment can also be applied to a measurement device of any of these methods.

[5. Light detection element] As described above, the photoelectric conversion element of this embodiment may have a light detection function that converts irradiated light into an electrical signal corresponding to the amount of received light and outputs it to an external circuit via an electrode. Therefore, the photoelectric conversion element according to the embodiment of the present invention can be particularly suitably used as a photodetection element having a photodetection function. Here, the photodetection element of this embodiment may be the photoelectric conversion element itself. In addition to the photoelectric conversion element, it may also include functional elements for voltage control and the like. [Example]

Examples are shown below in order to explain the present invention in more detail. The present invention is not limited to the following examples. Unless otherwise specified, the following examples were carried out under the conditions of normal temperature (20°C ± 15°C) and normal pressure (1 atm). In addition, unless otherwise specified, "%" and "parts" mean "mass %" and "mass parts" respectively.

＜Semiconductor materials used＞ (p-type semiconductor) As the p-type semiconductor material P-1, a polymer compound synthesized with reference to the method described in International Publication No. 2013/051676 was used. As the p-type semiconductor material P-2, a polymer compound synthesized with reference to the method described in International Publication No. 2011/052709 was used. As the p-type semiconductor material P-3, a trade name: PM6 manufactured by 1-material Co., Ltd. which is a polymer compound was used. As the p-type semiconductor material P-4, a trade name: PCE10 manufactured by 1-material Co., Ltd., which is a polymer compound, was used.

(n-type semiconductor) As the n-type semiconductor material N-1, a trade name: Guard Surf NC-1010 manufactured by Harves Co., Ltd. was used. As the n-type semiconductor material N-2, trade name: E100 manufactured by Frontier Carbon Co., Ltd. was used. As the n-type semiconductor material N-3, a trade name: Y6 manufactured by 1-material Co., Ltd. is used.

The specific structures of p-type semiconductor materials P-1 to p-type semiconductor materials P-4 and n-type semiconductor materials N-1 to n-type semiconductor materials N-3 are shown in Table 1 and Table 2 below.

[Table 1] p-type semiconductor chemical structure P-1 P-2 P-3 P-4

[Table 2] n-type semiconductor chemical structure N-2 N-3

＜Surface active agent used＞ The surfactants used in the examples are as follows. "F-556": Manufactured by DIC, a non-ionic fluorine-based surfactant with a poly(meth)acrylate structure. "R-40": Manufactured by DIC, a nonionic, fluorine-based surfactant with a poly(meth)acrylate structure. "KP-620": Manufactured by Shin-Etsu Chemical Industry Co., Ltd., a non-ionic surfactant with an organopolysiloxane structure. "KP-323": Manufactured by Shin-Etsu Chemical Industry Co., Ltd., a non-ionic surfactant with an organopolysiloxane structure.

The physical properties of the surfactant are shown in the table below. In the table below, "F" represents a fluorine atom.

[table 3] surfactant Traits Is there F Viscosity η (mPa·s) MP 556 liquid have 2700 3000 R-40 liquid have 5700 700 KP-620 liquid without 11200 - KP-323 liquid without 160 -

The viscosity eta of the surfactant is measured by the following method and conditions. The viscosity eta at a temperature of 25°C and a shear speed of 100 (S ^-1 ) was measured using the Modular Compact Rheometer MCR302 manufactured by Anton Paar.

The Mp (peak molecular weight) of the surfactant is measured by the following method and conditions. As the mobile phase of GPC, o-dichlorobenzene was used and flowed at a flow rate of 1.0 mL/min. As the pipe column, Shodex KD-806M manufactured by Showa Denko Co., Ltd. was used, and as the guard column, Shodex KD-G manufactured by Showa Denko Co., Ltd. was used.

As detectors, a UV-vis detector (manufactured by Shimadzu Corporation, SPD-M20A) and a differential refractive index detector (manufactured by Shimadzu Corporation, RID-10A) were used.

The compound (polymer) to be measured was mixed with 1-chloronaphthalene as a solvent at a concentration of 0.05% by mass, and stirred at 80° C. for 2 hours to dissolve the mixture to prepare a solution.

The obtained solution was injected into the measurement device (GPC) in an amount of 10 μL as a sample, and the peak molecular weight (Mp) was measured.

<Example 1> Mix pseudocumene, tetralin and butyl benzoate to a mass ratio of 87%, 10% and 3% respectively to prepare an ink solvent. As the surfactant, "F-556" manufactured by DIC Corporation was used. Mix the ink solvent and the surfactant to a mass ratio of 99.9%:0.1% to obtain mixture (a). In the mixture (a), the material P-1 which is a p-type semiconductor and the material N-1 which is an n-type semiconductor are mixed, and the mixture (b) is obtained. The mixing amount of the p-type semiconductor was set to 1.5% by mass relative to the entire ink composition (mixture (b)). The mixing amount of the n-type semiconductor is 1.5% by mass relative to the mass of the entire ink composition (mixture (b)). The obtained mixture (b) was stirred at 60° C. for 6 hours, and then filtered with a filter to obtain ink composition I-1. When the total of the solvent, p-type semiconductor, n-type semiconductor and surfactant contained in the ink composition I-1 is 100% by mass, the content ratio of the surfactant is 0.097% by mass.

<Example 2> Mix the ink solvent and the surfactant to a mass ratio of 99.0%:1.0% to obtain mixture (a). Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-2. When the total amount of the solvent, p-type semiconductor, n-type semiconductor and surfactant contained in the ink composition I-2 is 100% by mass, the content ratio of the surfactant is 0.97% by mass.

<Example 3> As a surfactant, "KP-620" manufactured by Shin-Etsu Chemical Industry Co., Ltd. was used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-3.

＜Comparative example 1＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-C1.

<Example 4> Mix pseudocumene and 1,2-dimethoxybenzene to a mass ratio of 97% and 3% respectively to prepare an ink solvent. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-4.

＜Comparative example 2＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 4 was performed to obtain ink composition I-C2.

<Example 5> As the p-type semiconductor, material P-2 is used, and as the n-type semiconductor, material N-2 is used. As the surfactant, "R-40" manufactured by DIC Co., Ltd. was used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-5.

<Example 6> As the p-type semiconductor, material P-2 is used, and as the n-type semiconductor, material N-2 is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-6.

＜Comparative Example 3＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 5 was performed to obtain ink composition I-C3.

<Example 7> As the p-type semiconductor, material P-3 is used, and as the n-type semiconductor, material N-2 is used. As an ink solvent, o-dichlorobenzene is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-7.

＜Comparative Example 4＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 7 was performed to obtain ink composition I-C4.

<Example 8> As the p-type semiconductor, material P-4 is used, and as the n-type semiconductor, material N-2 is used. As an ink solvent, o-dichlorobenzene is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-8.

＜Comparative Example 5＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 8 was performed to obtain ink composition I-C5.

<Example 9> As the p-type semiconductor, material P-1 is used, and as the n-type semiconductor, material N-2 is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-9.

<Comparative Example 6> Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 9 was performed to obtain ink composition I-C6.

<Example 10> As the p-type semiconductor, material P-1 is used, and as the n-type semiconductor, material N-3 is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-10.

<Comparative Example 7> Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 10 was performed to obtain ink composition I-C7.

<Example 11> As the p-type semiconductor, material P-3 is used, and as the n-type semiconductor, material N-3 is used. Except for the above matters, the same procedure as in Example 1 was performed to obtain ink composition I-11.

＜Comparative Example 8＞ Use a surfactant-free ink vehicle instead of mixture (a). Except for the above matters, the same procedure as in Example 11 was performed to obtain ink composition I-C8.

The preparation of the ink compositions of Examples and Comparative Examples is shown in the table below. In the table below, the added amount of the surfactant represents the value when the mixture (b) is 100% by mass.

[Table 4] Ink composition p-type semiconductor n-type semiconductor Solvent (mass ratio) surfactant Product name Adding amount (mass %) Comparative example 1 I-C1 P-1 N-1 Pseudocumene/tetralin/butyl benzoate (87/10/3) - - Example 1 I-1 F-556 0.097 Example 2 I-2 F-556 0.97 Example 3 I-3 KP-620 0.097 Comparative example 2 I-C2 Pseudocumene/1,2-dimethoxybenzene (97/3) - - Example 4 I-4 F-556 0.097 Comparative example 3 I-C3 P-2 N-2 Pseudocumene/tetralin/butyl benzoate (87/10/3) - - Example 5 I-5 R-40 0.097 Example 6 I-6 F-556 0.097 Comparative example 4 I-C4 P-3 o-Dichlorobenzene (100) - - Example 7 I-7 F-556 0.097 Comparative example 5 I-C5 P-4 - - Example 8 I-8 F-556 0.097 Comparative example 6 I-C6 P-1 Pseudocumene/tetralin/butyl benzoate (87/10/3) - - Example 9 I-9 F-556 0.097 Comparative example 7 I-C7 N-3 - - Example 10 I-10 F-556 0.097 Comparative example 8 I-C8 P-3 - - Example 11 I-11 F-556 0.097

＜Manufacturing and Evaluation of Photoelectric Conversion Elements＞ Using each ink composition produced in the Examples and Comparative Examples, a photoelectric conversion element was produced according to the following photoelectric conversion element production method A or production method B, and the dark current (Jd) was measured.

[Manufacturing method A of photoelectric conversion element] (A-1. Substrate preparation) A glass substrate (hereinafter simply referred to as the glass substrate) on which an ITO film as a first electrode is formed by a sputtering method to a thickness of 100 nm was prepared. Then, the glass substrate was surface-treated by ozone ultraviolet (UV) treatment.

(A-2. Formation of active layer) The ink composition is coated on the ITO film of the glass substrate by spin coating to form a coating film. The glass substrate on which the coating film was formed was placed on a hot plate, and the coating film was dried in the air at 70° C. for 2 minutes. Next, the glass substrate on which the coating film was formed was placed on a hot plate, and the coating film was further dried at 100° C. for 10 minutes in a nitrogen atmosphere. Thereby, an active layer is formed on the ITO film. The thickness of the active layer formed is approximately 250 nm.

(A-3. Formation of electron transport layer) Next, a 45% by mass isopropyl alcohol dispersion of zinc oxide nanoparticles (particle diameter 20 nm to 30 nm) (HTD-711Z, manufactured by Tayca Corporation) was prepared by adding 10% of the isopropyl alcohol dispersion. Dilute with twice the mass of 3-pentanol to prepare a coating liquid. The coating liquid was applied to the formed active layer with a thickness of 40 nm by spin coating, and heat treatment was performed at 70° C. for 5 minutes. Thereby, an electron transport layer is formed on the active layer.

(A-4. Formation of electrodes) Then, using a resistance heating evaporation device, an Ag film serving as an electrode (second electrode) was formed on the electron transport layer to a thickness of approximately 80 nm.

(A-5. Formation of sealing layer) Next, an ultraviolet (UV) curable sealant is applied around the glass substrate on which the electrode (second electrode) is formed, and the glass plate is bonded on top of the electrode, and then UV light is irradiated to cure the sealant. and sealing to obtain a photoelectric conversion element. The shape of the obtained photoelectric conversion element was a square of 2 mm×2 mm.

Through the above manufacturing method, a photoelectric conversion element A (photodetection element A) in which a glass substrate, a first electrode, an active layer, an electron transport layer, and a second electrode are provided in this order can be obtained.

[Method B for manufacturing photoelectric conversion element] (B-1. Preparation of substrate) Prepare a glass substrate on which an ITO film is formed to a thickness of 100 nm by sputtering. Then, the glass substrate was surface-treated by ozone UV treatment.

(B-2. Formation of electron transport layer) Next, the glass substrate was immersed in a polyethyleneimine 80% ethoxylated aqueous solution (37% by mass aqueous solution manufactured by Sigma-Aldrich) and diluted with water so that the concentration became 0.1% by mass. Obtain dilute solution for 5 min. Then, the glass substrate was lifted out of the diluted solution, placed on a hot plate, and dried in the air at 100° C. for 10 minutes.

Then, the dried glass substrate was washed with water, the washed glass substrate was placed on a hot plate, and dried in the air at 100° C. for 10 minutes. Thereby, an electron transport layer is formed on the ITO film serving as the first electrode.

(B-3. Formation of active layer) Next, the ink composition is coated on the electron transport layer formed on the ITO film by a slot die coating method to form a coating film. Then, a vacuum drying process (pressure 10 Pa, 70°C) was performed for 5 minutes. The glass substrate on which the dried coating film was formed was placed on a hot plate and dried at 100° C. for 12 minutes to form an active layer. The thickness of the active layer formed is approximately 530 nm.

(B-4. Formation of electrodes) Next, a suspension of poly(3,4-ethylenedioxythiophene)/polystyrenesulfonic acid dissolved in water (Clevios F HC Solar, manufactured by Heraeus) was applied by spin coating. Distributed on the formed active layer to form a coating film. The glass substrate with the coating film formed on the active layer was placed in an oven and dried at 85° C. for 30 minutes to form a second electrode. The thickness of the second electrode formed was approximately 120 nm.

(B-5. Formation of sealing layer) Next, an ultraviolet (UV) curable sealant is applied around the glass substrate on which the electrode (second electrode) is formed, and the glass plate is bonded on top of the electrode, and then UV light is irradiated to cure the sealant. and sealing to obtain a photoelectric conversion element. The shape of the obtained photoelectric conversion element was a square of 2 mm×2 mm.

Through the above manufacturing method, a photoelectric conversion element B (photodetection element B) in which a glass substrate, a first electrode, an electron transport layer, an active layer, and a second electrode are provided in this order can be obtained.

[Evaluation of photoelectric conversion elements] For the photoelectric conversion element manufactured by the above-mentioned manufacturing method A or manufacturing method B, JV was measured in a dark place to determine the dark current (Jd) at -5V. A source-meter (model 2450, manufactured by Keithley Company) was used for JV measurement.

＜Evaluation results＞ The evaluation results are shown in the table below. In the table below, the relative values of dark current (Jd) in Evaluation 1 to Evaluation 4 are relative values when the dark current in Evaluation 1 is set to 100. The Jd relative values of Evaluation 5 to Evaluation 6 are relative values when the dark current of Evaluation 5 is set to 100. The Jd relative values of Evaluation 7 to Evaluation 9 are relative values when the dark current of Evaluation 7 is set to 100. The relative values of Jd for evaluation 10 to evaluation 11, evaluation 12 to evaluation 13, evaluation 14 to evaluation 15, evaluation 16 to evaluation 17, and evaluation 18 to evaluation 19 are respectively the Jd values of evaluation 10, evaluation 12, evaluation 14, evaluation 16, and evaluation 18. The relative value when the dark current is set to 100. In the table below, "element A" means photoelectric conversion element A manufactured by manufacturing method A, and "element B" means photoelectric conversion element B manufactured by manufacturing method B.

[table 5] Ink composition Component structure Jd relative value Rating 1 I-C1 Component B 100 Rating 2 I-1 63 Rating 3 I-2 86 Rating 4 I-3 68 Rating 5 I-C2 Component B 100 Rating 6 I-4 47 Rating 7 I-C3 Component A 100 Rating 8 I-5 86 Rating 9 I-6 71 Rating 10 I-C4 Component A 100 Rating 11 I-7 12 Rating 12 I-C5 Component A 100 Rating 13 I-8 14 Rating 14 I-C6 Component B 100 Rating 15 I-9 69 Rating 16 I-C7 Component B 100 Rating 17 I-10 86 Rating 18 I-C8 Component B 100 Rating 19 I-11 32

From the above results, it is known that a photoelectric conversion element including an active layer made of a composition containing a surfactant has a lower dark current than a photoelectric conversion element including an active layer made of a composition containing no surfactant. In addition, it was found that even if the photoelectric conversion element including an active layer made of a composition containing a surfactant has either the structure of the photoelectric conversion element A or the photoelectric conversion element B, the dark current is reduced.

10: Photoelectric conversion element 11: Support base plate 12: First electrode 13:The first middle layer 14:Active layer 15: The second middle layer 16: Second electrode 17:Sealing components

FIG. 1 is a diagram schematically showing a structural example of a photoelectric conversion element.

10: Photoelectric conversion element

11: Support base plate

12: First electrode

13:The first middle layer

14:Active layer

15: The second middle layer

16: Second electrode

17:Sealing components

Claims (13)

A composition includes p-type semiconductor, n-type semiconductor, surfactant and solvent. The composition according to claim 1, wherein the p-type semiconductor is a polymer compound having a donor/acceptor structure. The composition according to claim 1, wherein the p-type semiconductor is selected from the group consisting of a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II). A polymer compound with more than one constituent unit, In formula (I), Ar ¹ and Ar ² each independently represent a trivalent aromatic heterocyclic group which may have a substituent, and Z represents any one of the following formulas (Z-1) to formula (Z-7) The basis represented by In Formula (Z-1) to Formula (Z-7), R represents: a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkenyl group which may have a substituent, cycloalkenyl group which may have a substituent, alkynyl which may have a substituent, cycloalkynyl which may have a substituent, aryl which may have a substituent, alkoxy which may have a substituent, cycloalkoxy which may have a substituent group, an aryloxy group which may have a substituent, an alkylthio group which may have a substituent, a cycloalkylthio group which may have a substituent, an arylthio group which may have a substituent, a monovalent heterocyclic group which may have a substituent, Substituted amino group which may have a substituent, imine residue which may have a substituent, amide group which may have a substituent, amide group which may have a substituent, substituted oxycarbonyl group which may have a substituent, cyano group , nitro group, a group represented by -C(=O)-R ^c , or a group represented by -SO ₂ -R ^d , R ^c and R ^d each independently represent: a hydrogen atom, an alkyl group which may have a substituent , a cycloalkyl group that may have a substituent, an aryl group that may have a substituent, an alkoxy group that may have a substituent, a cycloalkoxy group that may have a substituent, an aryloxy group that may have a substituent, or a substituted Monovalent heterocyclic group of the base, in formula (Z-1) to formula (Z-7), when there are two R, the two R may be the same or different, In formula (II), Ar ³ represents a divalent aromatic heterocyclic group. The composition according to claim 1, wherein the n-type semiconductor is a fullerene derivative. The composition according to claim 1, wherein the n-type semiconductor is a non-fullerene compound. The composition according to claim 1, wherein the solvent includes an aromatic hydrocarbon solvent. The composition according to claim 1, wherein the surfactant is a nonionic surfactant. The composition according to claim 1, wherein the surfactant is a compound with a poly(meth)acrylate structure. The composition according to claim 1, wherein the surfactant is a compound with an organopolysiloxane structure. The composition according to claim 1, wherein the surfactant is a fluorine-based surfactant. A film includes p-type semiconductor, n-type semiconductor and surfactant. An organic photoelectric conversion element includes a first electrode, the film according to claim 11, and a second electrode in sequence. A light detection element including the organic photoelectric conversion element described in claim 12.