JP2005056650A - Material for photoelectric conversion element, photoelectric conversion element, and cyanine compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide material for a photoelectric conversion element providing practical photoelectric conversion characteristics and having high durability and to provide the photoelectric conversion element. <P>SOLUTION: The material for the photoelectric conversion element is represented by general formula (1), and the photoelectric conversion element uses the material for the photoelectric conversion element. In the formula, a ring A and a ring B represent a heterocyclic ring, n1 is 1 or 2, R<SB>1</SB>-R<SB>3</SB>represent each a hydrocarbon group, a heterocyclic group, a halogen atom, or a group represented by general formula (2), and at least one of R<SB>1</SB>-R<SB>3</SB>is a group represented by general formula (2). A ring C represents an aromatic ring or the heterocyclic ring, and R<SB>4</SB>and R<SB>5</SB>are a group having a carboxyl group or the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photoelectric conversion element material and a photoelectric conversion element using the photoelectric conversion element material.

  Materials that convert light into electricity have been extensively researched with a focus on solar power generation, and solar cells using inorganic materials such as polycrystalline silicon solar cells and amorphous silicon solar cells have been put into practical use.

  Currently, with respect to solar cell manufacturing technology using inorganic materials, there remain problems such as reduction in manufacturing cost, increase in area, and increase in efficiency.

In response to this problem, it has been proposed to use organic materials as materials for photoelectric conversion elements, particularly from the viewpoint of reducing manufacturing costs. For example, the reports described in Non-Patent Literature 1 and Patent Literatures 1 to 3 by the research group of Gretzell et al. The reported material for photoelectric conversion elements is a metal complex dye using a metal such as ruthenium and an organic ligand compound that absorbs a wide range of visible light, and is known to have excellent photoelectric conversion characteristics. . On the other hand, since this metal complex dye is still an expensive dye, development of a photoelectric conversion element material using a relatively inexpensive organic dye has been desired. For example, ethylene compounds, cyanine compounds, and merocyanine compounds [Patent Documents 4 to 9] and the like have been proposed as conventional known organic dye photoelectric conversion element materials. The adsorption performance was low, and its photoelectric conversion characteristics were still not satisfactory.
Nature (Vol.353, 737-740, 1991) U.S. Pat. No. 4,927,721 WO94 / 04497 Japanese Patent Laid-Open No. 1-220380 JP 2003-78152 A JP 2001-52766 A JP 2000-106224 A JP 11-238905 A Japanese Patent Laid-Open No. 11-214731 Japanese Patent Laid-Open No. 11-214730

  An object of the present invention is to provide a photoelectric conversion element material and a photoelectric conversion element that provide practical photoelectric conversion characteristics and are excellent in durability.

  In order to solve these problems, the present inventors diligently studied the photoelectric conversion element material, and as a result, the present invention has been completed.

That is, the present invention
(A) A material for a photoelectric conversion element represented by the following general formula (1):

〔式中、環Aおよび環Bは、複素環を表し、n１は１または２であり、Ｒ_１〜Ｒ_３は水素原子、炭化水素基、複素環基、ハロゲン原子、または一般式（２）で示される基を表し、Ｒ_１〜Ｒ_３のうち少なくとも１つは下記一般式（２）で表される基である。〕

[Wherein, ring A and ring B represent a heterocyclic ring, n1 is 1 or 2, and R _{1 to} R ₃ are a hydrogen atom, a hydrocarbon group, a heterocyclic group, a halogen atom, or a general formula (2) And at least one of R _{1 to} R ₃ is a group represented by the following general formula (2). ]

〔式中、環Ｃは芳香環または複素環を表し、Ｒ_４およびＲ_５は、カルボキシル基、ヒドロキシル基、スルホン酸基、ホスホン酸基、リン酸基、珪酸基、ホウ酸基及びこれらのプロトン解離体からなる群から選ばれる少なくとも一種を有する基である。〕
（ロ） 好ましくは一般式（１）により表される光電変換素子用材料が下記一般式（３）、一般式（４）または一般式（５）で表される（イ）記載の光電変換素子用材料、

[Wherein, ring C represents an aromatic ring or a heterocyclic ring, and R ₄ and R ₅ represent a carboxyl group, a hydroxyl group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, a silicic acid group, a boric acid group, and protons thereof. It is a group having at least one selected from the group consisting of dissociators. ]
(B) The photoelectric conversion element according to (a), wherein the photoelectric conversion element material represented by the general formula (1) is preferably represented by the following general formula (3), general formula (4) or general formula (5) Materials,

〔一般式（３）〜（５）中、Ｒ_１〜Ｒ_３およびｎ１は一般式（１）と同様の基であり、Ｒ_１〜Ｒ_３のうち少なくとも１つは一般式（２）で表される基であり、Ｒ_６〜Ｒ_１６は炭
化水素基、含窒素官能基、含酸素官能基、含硫黄官能基、複素環基、ハロゲン原子を表し、a_１〜 a_５は０〜４の整数を表し、a_１〜 a_５が２以上のとき、同一芳香環上における複数のＲ_６〜Ｒ_１０はそれぞれ同じでも異なっていてもよく互いに連結して環を形成してもよく、Ｑ_１〜Ｑ_４はアルキレン基、−Ｎ（Ｒ）−（Ｒはアルキル基を表す）、酸素原子、硫黄原子またはセレン原子を表し、Zは電荷を中和させるのに対イオンが必要な場合の対イオンを表す。〕
（ハ） さらに好ましくは一般式（３）〜（５）中、Ｒ_２が一般式（２）で表される（ロ）記載の光電変換素子用材料、
（ニ） （イ）〜（ハ）のいずれかに記載の光電変換素子用材料を使用してなる光電変換素子、
（ホ） 下記一般式（６）により表されるシアニン化合物、

[In General Formulas (3) to (5), R _{1 to} R ₃ and n1 are the same groups as in General Formula (1), and at least one of R _{1 to} R ₃ is represented by General Formula (2). R _{6 to} R ₁₆ represent a hydrocarbon group, a nitrogen-containing functional group, an oxygen-containing functional group, a sulfur-containing functional group, a heterocyclic group, or a halogen atom, and a ₁ to a ₅ are 0 to 4 Represents an integer, and when a ₁ to a ₅ are 2 or more, a plurality of R _{6 to} R ₁₀ on the same aromatic ring may be the same or different, and may be connected to each other to form a ring, and Q ₁ to Q ₄ represents an alkylene group, -N (R) - (R represents an alkyl group), an oxygen atom, a sulfur atom or a selenium atom, Z is versus when necessary counterions to neutralize the charge Represents an ion. ]
(C) More preferably, in the general formulas (3) to (5), R ₂ is a material for a photoelectric conversion element according to (b) described by the general formula (2),
(D) A photoelectric conversion element using the photoelectric conversion element material according to any one of (a) to (c),
(E) a cyanine compound represented by the following general formula (6):

〔一般式（６）中、環Ｃ、Ｒ_４およびＲ_５は、一般式（２）と同様であり、Ｒ_６、Ｒ_７、Ｒ_１１、Ｒ_１２、a_１、a_２、Ｑ_１、Ｑ_２およびZは、一般式（３）と同様である。〕
（ヘ） 好ましくは環Ｃが下記一般式（７）により表される（ホ）記載のシアニン化合物、

[In General Formula (6), Rings C, R ₄ and R ₅ are the same as in General Formula (2), and R ₆ , R ₇ , R ₁₁ , R ₁₂ , a ₁ , a ₂ , Q ₁ , Q ₂ and Z are the same as those in the general formula (3). ]
(F) The cyanine compound described in (e), wherein ring C is preferably represented by the following general formula (7):

〔一般式（７）中、Ｒ_２１は炭化水素基、含窒素官能基、含酸素官能基、または含硫黄官能基、複素環基、ハロゲン原子を表し、a_２１は０〜４の整数を表し、＊は、環の連結基の位置を表す。〕
に関するものである。

[In General Formula (7), R ₂₁ represents a hydrocarbon group, a nitrogen-containing functional group, an oxygen-containing functional group, a sulfur-containing functional group, a heterocyclic group, or a halogen atom, and a ₂₁ represents an integer of 0 to 4. , * Represents the position of the linking group of the ring. ]
It is about.

  According to the present invention, it is possible to provide a material for a photoelectric conversion element having good adsorption performance to a semiconductor fine particle electrode substrate. Moreover, it is possible to provide a photoelectric conversion element that exhibits practical photoelectric conversion characteristics and is excellent in durability by using the photoelectric conversion element material. Furthermore, a cyanine compound suitable as the material for the photoelectric conversion element can be provided.

Hereinafter, embodiments of the present invention will be described in detail.
The photoelectric conversion element material of the present invention is represented by the general formula (1).

  Here, the “photoelectric conversion element” represents a known photoelectric conversion element (for example, a photoelectric chemical cell described in JP-A No. 1-220380), and the material for the photoelectric conversion element of the present invention is useful for these photoelectric conversion elements. Can be used.

  In general formula (1), ring A and ring B represent a heterocyclic ring, may have a substituent, and may have a condensed ring. As the heterocyclic ring, a heterocyclic 5-membered ring or 6-membered ring is preferable.

  Ring A is a monovalent heterocyclic ring, and specific examples include oxazole ring, benzoxazole ring, naphthoxazole ring, thiazole ring, benzothiazole ring, naphthothiazole ring, selenazole ring, benzoselenazole ring, naphthoselenazole ring Imidazole ring, benzimidazole ring, naphthimidazole ring, indolenine ring, indole ring, benzoindole ring, pyrazine ring, pyrimidine ring, pyridazine ring, indolizine ring, purine ring, pyrrole ring, rhodanine ring, pyridine ring or quinoline ring More preferably, 2-oxazole ring, 2-benzoxazole ring, 2-naphthoxazole ring, 2-thiazole ring, 2-benzothiazole ring, 2-naphthothiazole ring, 2-selenazole ring, 2-benzo Selenazole ring, 2-naphthele Nazole ring, 2-imidazole ring, 2-benzimidazole ring, 2-naphthimidazole ring, 2-3H-indole ring, 2-1H-benzo [e] indole ring, 2-1H-benzo [g] indole ring, 2 -Pyrazine ring, 2-pyrimidine ring, 3-pyridazine ring, 3-indolizine ring, 8-purine ring, 2-3H-pyrrole ring, 4-pyridine ring or 4-quinoline ring.

  Ring B is a divalent heterocyclic ring, and specific examples include 2,3-dihydrooxazole ring, 2,3-dihydrobenzoxazole ring, 1,2-dihydronaphthoxazole ring, 2,3-dihydrothiazole ring, 2,3-dihydrobenzothiazole ring, 1,2-dihydronaphthothiazole ring, 2,3-dihydroselenazole ring, 2,3-dihydrobenzoselenazole ring, 1,2-dihydronaphthselenazole ring, 2,3 -Dihydroimidazole ring, 2,3-dihydrobenzimidazole ring, 2,3-dihydronaphthimidazole ring, 1,3-dihydroindole ring, 1,3-dihydrobenzoindole ring, 1,2-dihydropyrazine ring, 1, 2-dihydropyrimidine ring, 1,6-dihydropyridazine ring, 2,3-dihydroindolizine ring, 7,8-dihydride A ropurine ring, 2,3-dihydropyrrole ring, 1,4-dihydropyridine ring, 1,4-dihydroquinoline ring or rhodanine ring, more preferably a 2,3-dihydrooxazol-2-ylidene group, 2,3 -Dihydrobenzoxazol-2-ylidene group, 1,2-dihydronaphthoxazole-2-ylidene group, 2,3-dihydrothiazol-2-ylidene group, 2,3-dihydrobenzothiazol-2-ylidene group, 1, 2-dihydronaphthothiazol-2-ylidene group, 2,3-dihydroselenazole-2-ylidene group, 2,3-dihydrobenzoselenazole-2-ylidene group, 1,2-dihydronaphthselenazole-2-ylidene group Group, 2,3-dihydroimidazol-2-ylidene group, 2,3-dihydrobenzimidazol-2-yl Den group, 2,3-dihydronaphthimidazol-2-ylidene group, 1,3-dihydroindole-2-ylidene group, 1,3-dihydrobenzoindole-2-ylidene group, 1,2-dihydropyrazine-2- Iridene group, 1,2-dihydropyrimidine-2-ylidene group, 1,6-dihydropyridazine-6-ylidene group, 2,3-dihydroindolizine-3-ylidene group, 7,8-dihydropurine-8-ylidene A group, 2,3-dihydropyrrol-2-ylidene group, 1,4-dihydropyridine-4-ylidene group, 1,4-dihydroquinolin-4-ylidene group or 2-thioxo-thiazoline-4-one.

When the heterocyclic ring of ring A and ring B has a substituent (hereinafter referred to as the substituent of ring A and ring B), a hydrocarbon group, a nitrogen-containing functional group, an oxygen-containing functional group, a sulfur-containing function Group, heterocyclic group,
A halogen atom is mentioned.

  Hydrocarbon groups, nitrogen-containing functional groups, oxygen-containing functional groups, and sulfur-containing functional groups include alkyl groups, cycloalkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, carboxyl groups, alkylcarbonyl groups, alkoxycarbonyl groups, and sulfonic acids. Group, alkylsulfonyl group, hydroxy group, aryl group, aryloxy group, acyloxy group, carbamoyl group, cyano group, nitro group, amino group, monosubstituted amino group, disubstituted amino group, sulfonamide group, substituted sulfonamide group, Examples include an acylamino group, an isothiocyanate group, an isocyanate group, and a thiocyanate group.

  Here, the hydrocarbon group means an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, and an aryl group, and the nitrogen-containing functional group means a carbamoyl group, a cyano group, a nitro group, an amino group, a mono-substituted amino group, a di group. Substituted amino group, acylamino group, isocyanate group, isothiocyanate group, oxygen-containing functional group means alkoxy group, aryloxy group, acyloxy group, carboxyl group, alkylcarbonyl group, alkoxycarbonyl group, hydroxy group, sulfur-containing The functional group means a sulfonic acid group, an alkylsulfonyl group, a sulfonamide group, a substituted sulfonamide group, and a thiocyanate group.

  The alkyl group is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may have a substituent. Specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, t-butyl group, n-pentyl group, and n-hexyl group. Unsubstituted alkyl groups such as 2-ethylhexyl group, n-decyl group, n-octadecyl group; chloromethyl group, 2-chloroethyl group, 2-bromoethyl group, 2-iodoethyl group, dichloromethyl group, fluoromethyl group, trimethyl group An alkyl group substituted with a halogen atom such as a fluoromethyl group; an alkyl group substituted with a hydroxy group such as a hydroxymethyl group, a 2-hydroxyethyl group or a 4-hydroxybutyl group; an alkoxy such as a methoxymethyl group or an ethoxymethyl group Substituted with a carboxyl group such as carboxymethyl group, 4-carboxybutyl group, etc. Alkyl group; alkyl group substituted by alkoxycarbonyl group such as methoxycarbonylmethyl group, 2-methoxycarbonylethyl group, 2-ethoxycarbonylethyl group, 3-ethoxycarbonylpropyl group; sulfomethyl group, 2-sulfoethyl group, 3- Examples thereof include an alkyl group substituted with a sulfonic acid group such as a sulfopropyl group.

  As the cycloalkyl group, a cycloalkyl group having 3 to 20 carbon atoms is preferable. Specific examples include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, and a 4-methylcyclohexyl group.

  The alkenyl group is preferably an alkenyl group having 2 to 20 carbon atoms. Specific examples include vinyl group, 2-carboxyvinyl group, 2-ethoxycarbonylvinyl group, allyl group, and oleyl group.

  As the alkynyl group, an alkynyl group having 2 to 20 carbon atoms is preferable. Specific examples include ethynyl group, butadiynyl group, 2-phenylethynyl group, and 4-carboxyphenylethynyl group.

  As an alkoxy group, a C1-C20 alkoxy group is preferable. Specific examples include a methoxy group, an ethoxy group, an iso-propyloxy group, and a benzyloxy group.

As the alkylcarbonyl group, an alkylcarbonyl group having 2 to 20 carbon atoms is preferable. Specific examples include a methylcarbonyl group, an ethylcarbonyl group, an iso-propylcarbonyl group, and a hydroxymethylcarbonyl group.

  As the alkoxycarbonyl group, an alkoxycarbonyl group having 2 to 20 carbon atoms is preferable. Specific examples include a methoxycarbonyl group, an ethoxycarbonyl group, an iso-propyloxycarbonyl group, and an n-butyloxycarbonyl group.

  As the alkylsulfonyl group, an alkylsulfonyl group having 1 to 20 carbon atoms is preferable. Specific examples include a methylsulfonyl group, an ethylsulfonyl group, an n-propylsulfonyl group, and an n-hexylsulfonyl group.

  The aryl group is preferably an aryl group having 6 to 26 carbon atoms, and may have a substituent. Specific examples include unsubstituted aryl groups such as phenyl group, 1-naphthyl group, and 9-anthracenyl group, alkyl groups such as 4-methylphenyl group, 2,4,6-trimethylphenyl group, and 4-t-butylphenyl group. An aryl group substituted with a group, an aryl group substituted with a halogen atom such as a 4-chlorophenyl group or a 2,6-dibromophenyl group, an alkoxy group such as a 4-methoxyphenyl group or a 3-iso-propyloxyphenyl group Substituted aryl groups, 4-N-methylaminophenyl groups, 4-N-ethylaminophenyl groups, aryl groups substituted with alkylamino groups such as 4-N-iso-propylaminophenyl groups, 4-N, Dialkylamino groups such as N-dimethylaminophenyl group, 4-N, N-diethylaminophenyl group, 4-N, N-di-n-propylaminophenyl group Such conversion aryl group.

As the aryloxy group, an aryloxy group having 6 to 26 carbon atoms is preferable. Specific examples include a phenyloxy group, a 4-methoxyphenyloxy group, a 3-chlorophenyloxy group, and a 4-methylphenyloxy group.
As the acyloxy group, an acyloxy group having 1 to 20 carbon atoms is preferable. Specific examples include an acetyloxy group and a benzoyloxy group.

  The carbamoyl group is preferably a carbamoyl group having 1 to 20 carbon atoms. Specific examples include N, N-dimethylcarbamoyl group and N-phenylcarbamoyl group.

  As the mono-substituted amino group, a mono-substituted amino group having 1 to 20 carbon atoms is preferable. Specific examples include an N-methylamino group, an N-ethylamino group, and an N-phenylamino group.

  The disubstituted amino group is preferably a disubstituted amino group having 2 to 20 carbon atoms. Specific examples include N, N-dimethylamino group, N, N-diethylamino group, and N, N-diphenylamino group.

  As the substituted sulfonamide group, a substituted sulfonamide group having 1 to 20 carbon atoms is preferable. Specific examples include N, N-dimethylsulfonamide group and N-phenylsulfonamide group.

  As the acylamino group, an acylamino group having 1 to 20 carbon atoms is preferable. Specific examples include an acetylamino group and a benzoylamino group.

  As the heterocyclic group, a heterocyclic group having 2 to 20 carbon atoms is preferable. Specific examples include 2-thienyl group, 2-furanyl group, 2-pyridyl group, 4-pyridyl group, 2-imidazolyl group, 2-benzimidazolyl group, 2-thiazolyl group, and 2-oxazolyl group.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  On the carbon atoms of the substituents of ring A and ring B, there may be further the above substituents.

In general formula (1), n1 is an integer of 1 or 2, and the value of n1 is related to the absorption long wavelength band of the photoelectric conversion element material described in general formula (1). Since the band moves to the long wavelength side, the band is selected according to the purpose and use when the photoelectric conversion element material described in the general formula (1) is used. When n1 is 2, the plurality of R _{1 s} and the plurality of R _{2 s} may be the same or different.

In General Formula (1), R _{1 to} R ₃ represent a hydrogen atom, a hydrocarbon group, a heterocyclic group, a halogen atom, or a group represented by General Formula (2), and at least one of R _{1 to} R ₃ Is a group represented by the general formula (2).

The hydrocarbon group for R _{1 to} R ₃ is preferably an alkyl group or an aryl group. The alkyl group is more preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may have a substituent. The aryl group is more preferably an aryl group having 6 to 26 carbon atoms and may have a substituent.
Specific examples of these alkyl groups and aryl groups include the same groups as the substituents of ring A and ring B.

Preferable specific examples of R _{1 to} R ₃ include a hydrogen atom, methyl group, ethyl group, n-propyl group, trifluoromethyl group, phenyl group, 1-naphthyl group, 4-chlorophenyl group, 2-thienyl group, 4 -A pyridyl group, a chlorine atom, and a bromine atom, and more preferably a hydrogen atom, a methyl group, an ethyl group, a phenyl group, and a chlorine atom.

  In general formula (2), ring C is an aromatic ring or a heterocyclic ring, and these may have a substituent. Specific examples thereof include chemical formulas (C1) to (C16), preferably, chemical formula (C1), chemical formula (C2), chemical formula (C6), chemical formula (C10), or chemical formula (C13).

［化学式（Ｃ１）〜（Ｃ１６）中、Ｒ_２１〜Ｒ_２８は、環Aおよび環Bの置換基と同様の基であり、a_２１は０〜４の整数であり、a_２２は０〜６の整数であり、a_２３は０〜８の整数であり、a_２４は０〜２の整数であり、a_２６は０〜３の整数であり、a_２７は０〜５の整数であり、a_２８は０〜１の整数であり、＊は環の連結基の位置を表す。］
化学式（Ｃ１）〜（Ｃ１６）中、Ｒ_２１〜Ｒ_２８は、環Aおよび環Bの置換基と同様の基であり、好ましくは、環Aおよび環Bの置換基と同様のアルキル基、アルコキシ基、カルボキシル基、スルホン酸基、アリール基、ニトロ基、複素環基またはハロゲン原子であり、より好ましくは、アルキル基、アルコキシ基、アリール基、ニトロ基、複素環基、またはハロゲン原子である。Ｒ_２１〜Ｒ_２８の好ましい具体例として、メチル基、エチル基、メトキシ基、フェニル基、ニトロ基、４−ピリジル基、カルボキシル基、メトキシ基、塩素
原子またはフッ素原子が挙げられる。

[In the chemical formulas (C1) to (C16), R _{21 to} R ₂₈ are the same groups as the substituents of the ring A and the ring B, a ₂₁ is an integer of 0 to 4, and a ₂₂ is 0 to 6 A ₂₃ is an integer from 0 to 8, a ₂₄ is an integer from 0 to 2, a ₂₆ is an integer from 0 to 3, a ₂₇ is an integer from 0 to 5, ₂₈ is an integer of 0 to 1, and * represents the position of the linking group of the ring. ]
In chemical formulas (C1) to (C16), R _{21 to} R ₂₈ are the same groups as the substituents of ring A and ring B, and preferably the same alkyl groups and alkoxy as the substituents of ring A and ring B Group, carboxyl group, sulfonic acid group, aryl group, nitro group, heterocyclic group or halogen atom, more preferably an alkyl group, alkoxy group, aryl group, nitro group, heterocyclic group or halogen atom. Preferable specific examples of R _{21 to} R ₂₈ include methyl group, ethyl group, methoxy group, phenyl group, nitro group, 4-pyridyl group, carboxyl group, methoxy group, chlorine atom or fluorine atom.

In the chemical formula (C1) ~ (C16), a 21 is preferably an integer of 0 to 2, 0 or 1 are more preferable. a ₂₂ is preferably an integer of 0 to 4, more preferably 0 or 1. a ₂₃ is preferably an integer of 0 to 4, more preferably 0 or 2. a ₂₄ is preferably 0 or 1. a ₂₆ is preferably 0 or 1. a ₂₇ is preferably 0 or 1. a ₂₈ is preferably 0.

In chemical formulas (C1) to (C16), * represents the position of the linking group of the ring, one of * is the nitrogen atom substituted by R ₄ and R _5, and the other of * is represented by the formula (1) R _{1 to} R ₃ are each connected to a substituted carbon atom.

In the general formula (2), R ₄ and R ₅ are selected from the group consisting of a carboxyl group, a hydroxyl group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, a silicic acid group, a boric acid group, and their proton dissociators. It represents a group having at least one kind of functional group, and an alkyl group, an alkenyl group and an aryl group substituted with these functional groups are preferred. In this case, examples of the alkyl group, alkenyl group, and aryl group include the same groups as the substituents of the rings A and B.

As the proton dissociation _{^{product, -COO -, -SO 3 -,}} -P (O) (OH) (O -), - B (OH) (O -) is preferred.

Specific examples of R ₄ and R ₅ include carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 18-carboxyoctadecyl group, 2-carboxyvinyl group, 4-carboxyphenyl group, 3,5-di- Examples thereof include a carboxyphenyl group, a hydroxymethyl group, a sulfomethyl group, a phosphomethyl group, a methyl silicate group, and a methyl borate group.

When R ₄ and R ₅ have a proton dissociator, they may have a salt-forming cation as a counter ion. As the salt-forming cation, inorganic or organic ammonium ions and alkali metal ions are preferable. Specific examples of inorganic or organic ammonium ions include ammonium ions, tetraethylammonium ions, tetrabutylammonium ions, and pyridinium ions. Specific examples of alkali metal ions include sodium ions, potassium ions, and lithium ions. Of these specific examples, tetrabutylammonium ion, sodium ion, and potassium ion are preferred.

  Among the compounds represented by the general formula (1), examples of preferable photoelectric conversion element materials include the general formulas (3) to (5).

In general formulas (3) to (5), R _{1 to} R ₃ and n1 are the same as in general formula (1), and at least one of R _{1 to} R ₃ is a group represented by general formula (2). It is.

In general formulas (3) to (5), R _{6 to} R ₁₀ are the same hydrocarbon groups, nitrogen-containing functional groups, oxygen-containing functional groups, sulfur-containing functional groups, and heterocyclic groups as the substituents of ring A and ring B. Represents a halogen atom.

In general formulas (3) to (5), a ₁ to a ₅ represent an integer of 0 to 4, preferably an integer of 0 to 2, and when a ₁ to a ₅ is 2 or more, the same aromatic ring A plurality of R _{6 to} R ₁₀ existing above may be the same as or different from each other, and may be connected to each other to form a ring, or preferred specific examples in which R _{6 to} R ₁₀ are connected to each other to form a ring. As —CH ₂ —CH ₂ —CH ₂ —CH ₂ —, —CH (Cl) —CH ₂ —CH ₂ —CH ₂ —, —CH═CH—CH═CH—, —C (Cl) ═CH -CH = CH-,
In the general formulas (3) to (5), R _{11 to} R ₁₆ are preferably an alkyl group, an alkenyl group, and an aryl group, and more preferably the same as those described in the description of the substituents of the ring A and the ring B. An alkyl group, an alkenyl group, and an aryl group. Preferable specific examples of R _{11 to} R ₁₆ include methyl group, ethyl group, n-propyl group, n-decyl group, n-octadecyl group, carboxymethyl group, 2-carboxyethyl group, 3-sulfopropyl group, 3 -A hydroxypropyl group, a vinyl group, a phenyl group, 4-carboxyphenyl group is mentioned.

In general formulas (3) to (5), Q _{1 to} Q ₄ represent an alkylene group, —N (R) —, an oxygen atom, a sulfur atom, or a selenium atom.

The alkylene group, preferably an alkylene group having 1 to 5 carbon atoms, as a specific example, methylene, -C _{(CH 3) 2} - and the like.

R in —N (R) — is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may have a substituent. Specific examples include a methyl group, an ethyl group, an n-butyl group, an n-decyl group, and an n-octadecyl group. Preferable specific examples of Q _{1 to} Q ₄ are —C (CH ₃ ) ₂ —, —N (CH ₃ ) —, a sulfur atom or an oxygen atom, and more preferably —N (CH ₃ ) —, sulfur. An atom or an oxygen atom.

In the general formulas (3) to (5), Z represents a counter ion when a counter ion is necessary for neutralizing the charge, and represents a cation or an anion. The charge of the whole molecule is neutralized by Z, and when R ₄ and R ₅ are groups having a proton dissociator such as a carboxyl group, the charge of these groups may be neutralized by a cation.

  The cation is preferably an inorganic or organic ammonium ion or alkali metal ion. Specific examples of inorganic or organic ammonium ions include tetraalkylammonium ions and pyridinium ions, and specific examples of alkali metal ions include sodium ions, potassium ions, and lithium ions.

  Anions include halide ions, aryl sulfonate ions, aryl disulfonate ions, alkyl sulfate ions, sulfate ions, thiocyanate ions, perchlorate ions, tetrafluoroborate ions, hexafluorophosphate ions, picrate ions or An acetate ion is mentioned. Also, ionic polymers can be used as charge balancing counterions.

  Specific examples of the halide ions include fluoride ions, chloride ions, bromide ions, and iodide ions.

  Specific examples of the aryl sulfonate ion include p-toluene sulfonate ion and p-chlorobenzene sulfonate ion.

  Specific examples of the aryl disulfonate ion include 1,3-benzenedisulfonate ion, 1,5-naphthalenedisulfonate ion, and 2,6-naphthalenedisulfonate ion.

  Specific examples of the alkyl sulfate ion include methyl sulfate ion and trifluoromethyl sulfate ion.

More preferable examples of the photoelectric conversion element material represented by the general formula (1) include a photoelectric conversion element material in which R ₂ is the general formula (2) in the general formulas (3) to (5). it can.

As a more preferable example of the photoelectric conversion element material represented by the general formula (1), the general formula (6
The material for photoelectric conversion elements represented by this can be mentioned.

In general formula (6), rings C, R ₄ and R ₅ are the same as in general formula (2), and R ₆ , R ₇ , R ₁₁ , R ₁₂ , a ₁ , a ₂ , Q ₁ , Q ₂ And Z are the same as those in the general formula (3).

  Particularly preferable examples of the photoelectric conversion element material represented by the general formula (1) include a photoelectric conversion element material in which the ring C is represented by the general formula (7) in the general formula (6). it can.

In the general formula (7), R ₂₁ and a ₂₁ are the same as those in the chemical formula (C1), * represents the position of the linking group of the ring, and one of * represents a nitrogen atom substituted by R ₄ and R _5. , * Represents that the other is connected to the carbon atom to which the ring C in the general formula (6) is connected.

  Although the specific example of the material for photoelectric conversion elements represented by General formula (1) is shown below using following chemical formula (D-1)-(D-42), this invention is not limited to these. .

Among the following chemical formulas (D-1) to (D-42), Z ₁ represents a counter ion that neutralizes charges, and preferred specific examples include the following chemical formulas Z _{1a to} Z _1k .

本発明の一般式（１）で表される光電変換素子用材料は、F. M. Harmer 著「ヘテロサイクリック・コンパウンズ−シアニンダイズ・アンド・リレーティッド・コンパウンズ（Heterocyclic Compounds-Cyanine Dyes and Related Compounds）」、ジョン・ウィリー・アンド・サンズ（John Willy & Sons）社、ロンドン、１９９４年刊等を参考に、文献および文献中に引用された方法等を参考にして製造することができる。

The material for the photoelectric conversion element represented by the general formula (1) of the present invention is “Heterocyclic Compounds-Cyanine Dyes and Related Compounds” by FM Harmer, With reference to John Willy & Sons, London, 1994, etc., it can be produced with reference to literature and methods cited in the literature.

  For example, in the general formula (1) of the present invention, when the ring A and the ring B are the same kind of heterocycle, the production can be performed by the following two-stage reaction.

  First, in the first stage, the following general formula (8) and general formula (9) are reacted in a solvent in the presence of a base at 20 ° C. to 180 ° C., preferably 50 ° C. to 150 ° C., and the following general formula (10 In the second stage, the general formula (10) obtained in the first stage can be prepared by using a hydrolysis reaction in a solvent in the presence of a base or an acid.

  Examples of the solvent used in the first stage include ethanol, iso-propanol, toluene, xylene, chlorobenzene, N, N-dimethylformamide, dimethylimidazolidinone, acetic anhydride, dimethyl sulfoxide, chloroform, and hexane. Examples of the base include morpholine, piperidine, pyrrolidine, triethylamine, potassium t-butoxide, sodium hydride, and potassium carbonate.

  Examples of the solvent used in the second stage include ethanol, iso-propanol, toluene, xylene, chlorobenzene, N, N-dimethylformamide, dimethylimidazolidinone, acetic anhydride, dimethyl sulfoxide, chloroform, hexane, and water. . Examples of the base include sodium hydroxide, potassium hydroxide, sodium ethoxide, sodium methoxide, potassium-t-butoxide, sodium hydride, and triethylamine. Examples of the acid include hydrochloric acid, nitric acid, sulfuric acid, hydrobromic acid, acetic acid, trifluoroacetic acid, phosphoric acid, and p-toluenesulfonic acid.

［式中、環AおよびR_１は、一般式（１）と同様である。］

[Wherein, ring A and R ₁ are the same as in general formula (1). ]

［式中、環Ｃは、一般式（２）と同様であり、Ｒ_３１およびＲ_３２は、カルボキシル基、ヒドロキシル基、スルホン酸基、ホスホン酸基、リン酸基、珪酸基またはホウ酸基のエステル体である基を有する置換基である。］
エステル体としては、メチルエステル、エチルエステルが好ましい。

[Wherein, ring C is the same as in general formula (2), and R ₃₁ and R ₃₂ are a carboxyl group, a hydroxyl group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, a silicic acid group or a boric acid group. It is a substituent having a group which is an ester form. ]
As an ester body, methyl ester and ethyl ester are preferable.

［式中、環A、環B、R_１およびR_２は、一般式（１）と同様であり、環Ｃは、一般式（２）と同様であり、Ｒ_３１およびＲ_３２は、一般式（９）と同様である。］

[Wherein, ring A, ring B, R ₁ and R ₂ are the same as in general formula (1), ring C is the same as in general formula (2), and R ₃₁ and R ₃₂ are Same as (9). ]

  Moreover, as a manufacturing method in case the ring A and the ring B are different types of heterocycles in the general formula (1), they can be manufactured in the following three stages. That is, in the first stage, the general formula (8) and the following general formula (11) are reacted in a solvent at 20 ° C. to 180 ° C., preferably 80 ° C. to 150 ° C., to obtain the following general formula (12). Thereafter, the general formula (12) and the general formula (8) different from the general formula (8) used in the first-stage reaction are added in a solvent in the presence of a base at 20 ° C to 180 ° C. The reaction is preferably carried out at 50 ° C. to 150 ° C. to make General Formula (10) in which Ring A and Ring B are different types of heterocycles, and then hydrolyzed using the same method as in the hydrolysis reaction. Can be manufactured.

  Examples of the solvent used in the first step when ring A and ring B are different types of heterocycles include acetic anhydride, ethanol, iso-propanol, toluene, xylene, chlorobenzene, N, N-dimethylformamide, dimethyl Examples include imidazolidinone, dimethyl sulfoxide, chloroform, and hexane.

  Examples of the solvent used in the second step when ring A and ring B are different types of heterocycles include ethanol, iso-propanol, toluene, xylene, chlorobenzene, N, N-dimethylformamide, and dimethylimidazolidinone. , Acetic anhydride, dimethyl sulfoxide, chloroform, hexane.

  Examples of the base used in the second step include morpholine, piperidine, pyrrolidine, triethylamine, potassium t-butoxide, sodium hydride, and potassium carbonate.

［式中、環Ｃは、一般式（２）と同様であり、Ｒ_３１およびＲ_３２は、一般式（９）と同様である。］

[Wherein, ring C is the same as in general formula (2), and R ₃₁ and R ₃₂ are the same as in general formula (9). ]

［式中、環AおよびR_１は、一般式（１）と同様であり、環Ｃは、一般式（２）と同様であり、Ｒ_３１およびＲ_３２は、一般式（９）と同様である。］
以上、詳述した一般式（１）および一般式（３）〜（６）により表される光電変換素子用材料は、可視光の波長領域で光増感することができ、半導体微粒子への吸着性能が高く、実用的な光電変換特性を与えるため光電変換素子用材料として非常に好ましい。

[Wherein, ring A and R ₁ are the same as in general formula (1), ring C is the same as in general formula (2), and R ₃₁ and R ₃₂ are the same as in general formula (9). is there. ]
As described above, the photoelectric conversion element materials represented by the general formula (1) and the general formulas (3) to (6) described above can be photosensitized in the wavelength region of visible light, and adsorbed on the semiconductor fine particles. It is highly preferable as a material for a photoelectric conversion element because it has high performance and provides practical photoelectric conversion characteristics.

Next, the photoelectric conversion element according to the present invention will be described.
The photoelectric conversion element according to the present invention is a photoelectric conversion element formed by using the material for the photoelectric conversion element of the general formula (1) and the general formulas (3) to (6), and preferably the general formula (1) and It is a photoelectric conversion element using the electrode which couple | bonded and / or adsorb | sucked the photoelectric conversion element material of General formula (3)-(6) to the semiconductor fine particle, More preferably, as shown in FIG. , A conductive layer 3, a dye-adsorbing semiconductor fine particle layer 5, a charge transfer layer 6, a conductive layer 4 and a substrate 2 in this order.

  Hereinafter, the substrate, the conductive layer, the dye-adsorbing semiconductor fine particle layer, and the charge transfer layer will be described.

The substrate used in the photoelectric conversion element of the present invention is not particularly limited, but is preferably a glass and resin substrate. Specific examples of the glass include borosilicate glass, silicate glass, soda lime glass, Examples include silicate glass such as alkali silicate glass, potassium lime glass, lead glass or barium glass, borate glass, and phosphate glass. Specific examples of the resin include polycarbonate, polyacrylonitrile, Examples thereof include fluorine resins such as polyethylene terephthalate or Teflon (registered trademark).

  The substrate may be transparent or translucent, and may be colored, but is preferably transparent and more preferably a substrate having a visible light transmittance of 70% or more. The shape of the substrate is not particularly limited, but is preferably a plate shape or a film shape.

  The conductive layer used in the photoelectric conversion element of the present invention is a conductive layer formed of a metal, a conductive metal oxide, or a conductive organic substance, and the metal used for the conductive layer preferably has a work function of 3 .5 to 6.0 eV metal. Specific examples include platinum, gold, silver, copper, cobalt, iron, nickel, palladium, vanadium, rhodium, tungsten, aluminum and zinc.

  The conductive metal oxide is preferably indium-tin composite oxide or fluorine-doped tin oxide.

  The conductive organic material is preferably a carbon material used for a general carbon electrode, a hydrocarbon such as fullerene, carbon nanotube or polyacetylene, or a conductive material such as polyaniline and polythiophene which may have a substituent. Charge transfer complex such as a functional polymer, tetrathiafulvalene-tetracyanoquinodimethane.

  The method of forming the conductive layer on the substrate is not limited as long as it is a method of forming the conductive layer on the substrate by coating or vapor deposition, but a sputtering method, vapor deposition method, or spin coating method is preferable. The thickness of the conductive layer is preferably 0.02 to 10 mm.

The conductive layer formed on the substrate should have a lower surface resistance. Preferably, the surface resistance range is 100 Ω / cm ² or less, and more preferably 30 Ω / cm ² or less.

  The dye-adsorbing semiconductor fine particle layer used in the photoelectric conversion element of the present invention is a layer composed of a semiconductor fine particle layer and a dye layer. The semiconductor fine particle layer is a layer formed of semiconductor fine particles, and the dye layer is a layer of photoelectric conversion element material formed by bonding and / or adsorbing the photoelectric conversion element material of the present invention to the semiconductor fine particle layer. It is.

The material used for the semiconductor fine particles is preferably a metal oxide. Specific examples include TiO ₂ , Fe ₂ O ₃ , WO ₃ , ZnO, Nb ₂ O ₅ , and SnO ₂ , preferably TiO ₂ , ZnO, and SnO ₂ , and more preferably TiO ₂ .

Further, the material used for the semiconductor fine particles may be one kind or two or more kinds. Furthermore, a mixture of the same metals as those used for the conductive layer and the materials used for the semiconductor fine particles may be used.
The particle size of the semiconductor fine particles is preferably 5 to 10 mm, more preferably 5 to 200 nm, and particularly preferably 8 to 50 nm.

In the case of forming a semiconductor fine particle layer, it is preferable to apply a fine thin film layer as an undercoat layer on a substrate on which a conductive layer is formed, as described in JP-A-11-312541.
As a method for forming the semiconductor fine particle layer, a method in which a colloidal solution or dispersion solution of semiconductor fine particles is prepared and applied on the substrate on which the conductive layer is formed is preferable.

As a method for preparing a colloidal solution of semiconductor fine particles, “Thin Film Coating Technology by Sol-Gel Method” (1995) of the Technical Information Association, “Latest of dye-sensitized solar cells” published by CMC Co., Ltd. A preparation method by a sol-gel method described in “Technology” (2001) and the like is preferable. Examples of a method for preparing a dispersion solution of semiconductor fine particles include a method in which a material used for semiconductor fine particles is pulverized and then dispersed in a dispersion solvent to obtain a dispersion solution.
Examples of the method of pulverizing the material used for the semiconductor fine particles include a method of grinding with a mortar, a method of pulverizing with a mill, and the like.

  Specific examples of the dispersion solvent for dispersing the semiconductor fine particles prepared by such a method include water, methanol, ethanol, iso-propyl alcohol, dichloromethane, acetone, acetonitrile, and ethyl acetate. When dispersing, if necessary, a polymer, a surfactant, an acid, a chelating agent, or the like may be used as a dispersion aid.

  Specific examples of a method for applying the colloidal solution or dispersion of semiconductor fine particles to a substrate on which a conductive layer is formed include a doctor blade method, a roller method, a dipping method, an air knife method, and a spin method. , Spray method, screen printing method, and the like, and doctor blade method, roller method, spin method, and screen printing method are preferable.

  The semiconductor fine particle layer need not be limited to a single layer. It is also possible to apply a colloidal solution or dispersion solution of semiconductor fine particles with different particle diameters in multiple layers, and colloidal solution or dispersion solution of semiconductor fine particles with different types of materials or different binder and additive compositions. It can also be applied. When applying to a multilayer, it may be overcoated several times to dozens of times. In the case of overcoating, the screen printing method is preferred.

  The thickness of the semiconductor fine particle layer is preferably 0.1 to 200 μm. More preferably, it is 1-100 micrometers. The coating amount of the semiconductor fine particles per square meter of the substrate on which the conductive layer is formed is preferably 0.5 to 400 g, and more preferably 5 to 100 g.

  After the application of the semiconductor fine particle colloidal solution or dispersion, heat treatment is preferably performed to improve the coating strength. The range of the heat treatment temperature is preferably 40 ° C. or higher and lower than 700 ° C., and more preferably 100 ° C. or higher and lower than 550 ° C. The heat treatment time is about 10 minutes to 10 hours, preferably 30 minutes to 2 hours. In the case of using a substrate having a low melting point such as a resin substrate, high temperature treatment is not preferable, and it is preferable to perform heat treatment at a temperature lower than a temperature at which the substrate is altered or deformed.

  Furthermore, the surface purity of the semiconductor fine particles may be increased after the heat treatment, or a plating treatment using titanium tetrachloride or titanium trichloride may be performed. It is preferable to adjust the pH of the surface of the semiconductor fine particles by acid or base treatment.

  The semiconductor fine particle layer preferably has a large surface area. For this reason, it is preferable that the surface area in the state coated on the substrate on which the conductive layer is formed is 10 to 3000 times the projected area.

  The method for forming the dye layer is not particularly limited as long as the layer is formed by bonding and / or adsorbing to the semiconductor fine particle layer, but after dissolving the photoelectric conversion element material of the present invention in a solvent, A method of immersing the substrate on which the conductive layer and the semiconductor fine particle layer are formed in the solution for a predetermined time is preferable.

The solvent used for forming the dye layer is not limited as long as it does not hurt the material of the substrate on which the semiconductor fine particle layer is formed due to alteration or deformation, and dissolves the photoelectric conversion element material of the present invention. Specific examples of the solvent include alcohols such as methanol, ethanol and iso-propanol, acetonitrile, chloroform, dichloromethane, N, N-dimethylformamide, toluene, acetone, hexane or water. Preferred are methanol, ethanol, and acetonitrile.
The solution used for forming the dye layer may be composed of at least one kind of the material for a photoelectric conversion element of the present invention, or may be a mixture of two or more kinds.

  Moreover, it is also possible to use together the material for photoelectric conversion elements of this invention, and a well-known pigment | dye. Specific examples of known dyes include known porphyrin dyes, ruthenium complex dyes, methine dyes, squarylium dyes, xanthene dyes, phenazinone dyes, triphenylmethane dyes, coumarin dyes or phthalocyanine dyes.

The concentration of the solution used for forming the dye layer may be adjusted to 0.0001 to 1.0 mol / L, but preferably 0.1 to 100 mM / L. Here, M represents mol / L (hereinafter the same).
The temperature and time for immersing the substrate on which the conductive layer and the semiconductor fine particle layer are formed in the solution used for forming the dye layer is preferably from room temperature to the reflux temperature of the solvent, 10 minutes to 1000 hours, respectively.

  The charge transfer layer used in the photoelectric conversion element of the present invention has a function of replenishing electrons to the oxidant of the photoelectric conversion element material of the present invention or replenishing holes to the reductant of the photoelectric conversion element material. It is a layer containing a transport material.

  The charge transport material is preferably an electrolytic solution in which a compound having redox ability is dissolved in an organic solvent, a gel electrolyte in which the electrolytic solution is impregnated in a polymer matrix, a molten salt having redox ability, a solid electrolyte, and the like. .

The electrolytic solution used as the charge transport material is preferably composed of an electrolyte, a solvent, and an additive.
The electrolyte used in the electrolytic solution is preferably sodium perchlorate, a quaternary ammonium salt halide, tetraalkylammonium PF ₆ , tetraalkylammonium BF ₄ , metal halide, bromine or iodine.

  Specific examples of the halide of the quaternary ammonium salt include tetraalkylammonium chloride, tetraalkylammonium bromide, and tetraalkylammonium iodide, with tetraethylammonium iodide being preferred.

  Specific examples of the metal halide include lithium chloride, sodium chloride, potassium chloride, lithium iodide, sodium iodide, potassium iodide, cesium iodide, lithium bromide, sodium bromide, potassium bromide, and cesium bromide. Can be mentioned.

Preferable specific examples of the electrolyte used in the electrolytic solution include sodium perchlorate, tetraalkylammonium iodide, iodine or lithium iodide. Moreover, the electrolyte used for electrolyte solution may be used independently and may be used together 2 or more types.
The concentration of the electrolyte used in the electrolytic solution is preferably 0.1 mM or more and 10 M or less, more preferably 0.1 mM or more and 5.0 M or less, and further preferably 0.1 mM or more. 1.0 M or less.

The solvent used in the electrolytic solution is preferably a solvent having a low viscosity and a high dielectric constant. Specific examples thereof include cyclic or chain forms such as dioxane, diethyl ether, ethylene glycol dialkyl ether, and propylene glycol dialkyl ether. Ethers; alcohols such as methanol, ethanol and ethylene glycol monoalkyl ether; polyhydric alcohols such as ethylene glycol, polyethylene glycol and glycerin; acetonitrile; Nitriles such as methoxyacetonitrile and benzonitrile; carbonates such as ethylene carbonate and propylene carbonate; dimethyl sulfoxide, sulfolane and the like.
Moreover, the solvent used for electrolyte solution may be used independently and may be used together 2 or more types.

The additive used in the electrolytic solution is an additive that changes the oxidation-reduction characteristics of the electrolytic solution, and can be added to the electrolytic solution as desired. As the additive, quinones, organic bases, metal complexes, and pyridinium salts are preferable. Specific examples include quinones such as hydroquinone and dicyanodichloroparabenzoquinone; organic bases such as 4-t-butylpyridine, viologen, 2-picoline and triethanolamine; metal complexes such as ferrocene-ferricyanate and porphyrin. A pyridinium salt such as methyl viologen is preferable, and 4-t-butylpyridine and triethanolamine are preferable. Moreover, the additive used for electrolyte solution may be used independently and may be used together 2 or more types.
The concentration of the additive used in the electrolytic solution is preferably 0.001 mM or more and 1.0 M or less, and more preferably 0.001 mM or more and 0.5 M or less.

Specific examples of the polymer used for the gel electrolyte used as the charge transport material include polyacrylonitrile and polyvinylidene fluoride.
The molten salt used as the charge transport material is preferably an ion conductive salt comprising a combination of a cationic species and an anionic species. Specific examples include tetraalkylammonium cations, imidazolium cations, pyridinium cations, trialkylsulfonyl cations and the like as cation species, and iodine anions (I ⁻ , I ₃ ⁻ ), aluminum chloride anions (AlCl) as anion species. ₄ ^-, AlCl ₇ ^-), a fluorine-containing anion _{^{[BF 4 -, PF 6 -,}} CF 3 SO 3 -, n (CF 3 SO 2) 2 -, F (HF) n - ] and the like. Moreover, the molten salt used as a charge transport material may be used alone or in combination of two or more.

  The solid electrolyte used as the charge transport material is preferably a hole transport material, a conductive polymer, a metal halide, a metal thiocyanide, a metal cyanide, or a metal sulfate. Hole transport materials such as N, N-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine and other aromatic amines, substituted or unsubstituted Conductive polymers such as polythiophene and polypyrrole, metal halides such as copper chloride, copper bromide, copper iodide, metal thiocyanides such as copper thiocyanide, metal cyanides such as copper cyanide or Examples thereof include metal sulfates such as copper sulfate, and solid electrolytes used as charge transport materials may be used alone or in combination of two or more.

In order to further increase the strength of the element, one or more other layers such as a protective layer and an undercoat layer may be formed in each layer.
Furthermore, the photoelectric conversion element of the present invention is preferably sealed using a resin such as epoxy resin, silicon rubber, silicon resin, fluororubber, or fluororesin. These resins can be used alone or in combination of two or more.

The photoelectric conversion element of the present invention is considered to be used for solar cells, indoor power generation elements, photosensors (photocells, color sensors, photosensitive drums for copying machines, imaging devices), window glass or films that can generate power. It is done.
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

A method for producing a compound of the present invention having the chemical formula D-1 and Z ₁ being an iodide ion (hereinafter abbreviated as D-1-Z _1d ) is shown in the reaction formula (1).
Production of D-1-Z _{1d In} a 1 L three-necked flask under a nitrogen atmosphere, 15.2 g (50 mmol) of 3-ethyl-2-methylbenzothiazolium iodide, 4-N, N-bis (ethoxy) Carbonylmethyl) aminobenzaldehyde (7.3 g, 25 mmol) and absolute ethanol (400 mL) were charged, and piperidine (10 mL) was charged with stirring, followed by heating under reflux for 6 hours. Subsequently, ethanol and piperidine were distilled off under reduced pressure, and the residue was purified by column chromatography. The obtained solid was charged into a 300 mL three-necked flask under nitrogen atmosphere together with 100 mL of ethanol and 5 mL of 5N aqueous sodium hydroxide solution. And stirred at room temperature for 12 hours. Here, the N represents mol / L (the same applies hereinafter). The solvent of the reaction solution was distilled off under reduced pressure, and the resulting solid was stirred in 1N hydrochloric acid. This solid was washed with water and collected by filtration. The filtered solid was recrystallized from a mixed solvent of methanol and water to obtain 4.1 g of D-1-Z _1d . The analysis results of D-1-Z _1d are shown below.
Analysis result of D-1-Z _1d FD-MS 572 (M ⁺ -iodide molecular weight)
Elemental analysis: calculated value: C; 53.22, H; 4.32, N; 6.01
: Analytical value: C; 53.21, H; 4.45, N; 6.11
HPLC purity> 99 area%

The production method of the compound of the present invention having the chemical formula D-2 and Z ₁ being iodide ion (hereinafter abbreviated as D-2-Z _1d ) is shown in the reaction formula (2).
Preparation of D-2-Z _{1d In} Example 1, instead of using 3-ethyl-2-methylbenzothiazolium iodide, 1-ethyl-2-methyl-naphtho [1,2-d] thiazo 5.3 g of D-2-Z _1d was obtained in the same manner as in Example 1 except that 17.7 g of rhodium iodide was used. The analysis results of D-2-Z _1d are shown below.
Analysis result of D-2-Z _1d FD-MS 672 (M ⁺ -iodide molecular weight)
Elemental analysis: calculated value: C; 58.57, H; 4.29, N; 5.25
: Analytical value: C; 58.62, H; 4.12, N; 5.28
HPLC purity> 99 area%

A method for producing a compound of the present invention having the chemical formula D-7 and Z ₁ being an iodide ion (hereinafter abbreviated as D-7-Z _1d ) is shown in the reaction formula (3).
Preparation of D-7-Z _{1d In} Example 1, instead of using 3-ethyl-2-methylbenzothiazolium iodide and 4-N, N-bis (ethoxycarbonylmethyl) aminobenzaldehyde, 3-ethyl -2-Methyl-benzoselenazolium iodide 17.6 g and 4-N, N-bis (ethoxycarbonylethyl) aminobenzaldehyde were used in the same manner as in Example 1 except that D-7- 7.3 g of Z _1d was obtained. The analysis results of D-7-Z _1d are shown below.
Analysis result of D-7-Z _1d FD-MS 696 (M ⁺ -iodide molecular weight)
Elemental analysis: calculated value: C; 57.07, H; 4.93, N; 6.05
: Analytical value: C; 57.96, H; 4.99, N; 6.23
HPLC purity> 99 area%

A method for producing a compound of the present invention having the chemical formula D-10 and Z ₁ being iodide ion (hereinafter abbreviated as D-10-Z _1d ) is shown in the reaction formula (4).
Production of D-10-Z _{1d In} Example 1, 3-ethyl-2-methylbenzothiazolium iodide and 4-
Instead of using N, N-bis (ethoxycarbonylmethyl) aminobenzaldehyde, 18.3 g of 3-ethyl-1,1,2-trimethyl-1H-benzoindolinium iodide and 4-N, N-bis (4 8.3 g of D-10-Z _1d was obtained in the same manner as in Example 1 except that 10.4 g of -ethoxycarbonylphenyl) -4-aminobenzaldehyde was used. The analysis results of D-10-Z _1d are shown below.
Analysis result of D-10-Z _1d FD-MS 816 (M ⁺ ) (M ⁺ -iodide molecular weight)
Elemental analysis: calculated: C; 69.98, H; 5.34, N; 4.45
: Analytical value: C; 70.06, H; 5.28, N; 4.73
HPLC purity> 99 area%

A method for producing a compound of the present invention having the chemical formula D-19 and Z ₁ being an iodide ion (hereinafter abbreviated as D-19-Z _1d ) is shown in the reaction formula (5).
Preparation of D-19-Z _{1d In} Example 1, instead of using 3-ethyl-2-methylbenzothiazolium iodide and 4-N, N-bis (ethoxycarbonylmethyl) aminobenzaldehyde, 1-ethyl Example 1 except that 16.5 g of -2,3,3,6-tetramethyl-3H-indolium iodide and 8.6 g of 4-N, N-bis (ethoxycarbonylmethyl) aminonaphthalenecarbaldehyde were used. By the same operation, 6.1g of D-19-Z _1d was obtained. The analysis results of D-19-Z _1d are shown below.
Analysis result of D-19-Z _1d FD-MS 670 (M ⁺ ) (M ⁺ -iodide molecular weight)
Elemental analysis: calculated value: C; 67.74, H; 6.06, N; 5.27
: Analytical value: C; 69.99, H; 6.12, N; 5.18
HPLC purity> 99 area%

Photoelectric conversion elements were prepared by the following operations (J1) to (J4), and the photoelectric conversion characteristics of the photoelectric conversion elements were measured by the following operation (J5).
(J1) In a Teflon (registered trademark) coated stainless steel container, titanium dioxide fine particles (Nippon Aerosil Co., Ltd., Degussa P-25) 15 g, deionized water 45 g, dispersant [Aldrich, Triton X-100] 1 g and 30 g of zirconia beads having a diameter of 0.5 mm were added, and dispersion treatment was performed at 1500 rpm for 2 hours using a sand grinder mill. Zirconia beads were removed from the obtained dispersion by filtration. The average particle diameter of the titanium dioxide fine particles in the obtained dispersion was 2.5 μm.

(J2) Using a glass rod on a glass substrate with a transparent electrode having an area of 2 square centimeters [TCO-glass-U: surface resistance of about 30Ω / cm ² manufactured by Asahi Glass Co., Ltd.], the titanium dioxide dispersion prepared in (J1) It was applied (application area was 1 cm ² , application amount was 20 g / m ² ) and air-dried for 1 day. Next, the glass substrate with a transparent electrode coated with this titanium dioxide dispersion is placed in an electric furnace, baked at 450 ° C. for 30 minutes, cooled to room temperature, and taken out to form a semiconductor fine particle having a substrate, a conductive layer and a semiconductor fine particle layer. An electrode substrate was used.

(J3) The semiconductor fine particle electrode substrate prepared in (J2) was immersed in an ethanol solution (3 × 10 ⁻⁴ mol / L) of compound D-1-Z _1d for 15 hours. After that, the semiconductor fine particle electrode substrate taken out from the solution is immersed in a 2-mol% 2-t-butylpyridine acetonitrile solution for 15 minutes, washed with ethanol, air-dried, and adsorbed D-1-Z _1d. A semiconductor fine particle electrode substrate was obtained.

(J4) Platinum vapor deposited glass of the same size is superimposed on the semiconductor fine particle electrode substrate adsorbed with D-1-Z _1d prepared in (J3), and then capillary action is used in the gap between the two glasses. Then, the electrolytic solution was impregnated and sealed with an epoxy sealant to produce a photoelectric conversion element having the configuration shown in FIG. As the electrolytic solution, a solution in which 0.13 g of lithium iodide and 0.13 g of iodine were dissolved in 10 mL of a mixed solution of ethylene carbonate and acetonitrile (4: 1 vol / vol) was used.

(J5) Using simulated sunlight with a light intensity of 98 mW / cm ² generated from a 500 W xenon lamp (manufactured by Ushio) and transmitted using an AM 1.5G filter (manufactured by Oriel) and an ultraviolet cut filter (J4 The photoelectric conversion characteristics of the photoelectric conversion elements prepared in (1) were measured and summarized in Table 1.

In Example 6, instead of using D-1-Z _1d , a photoelectric conversion element was produced in the same manner as in Example 6 except that D-2-Z _1d was used. The photoelectric conversion characteristics of the produced photoelectric conversion elements were measured by the same method as in Example 6, and are summarized in Table 1.

In Example 6, a photoelectric conversion element was produced in the same manner as in Example 6 except that D-7-Z _1d was used instead of using D-1-Z _1d . The photoelectric conversion characteristics of the produced photoelectric conversion elements were measured by the same method as in Example 6, and are summarized in Table 1.

In Example 6, a photoelectric conversion element was produced in the same manner as in Example 6 except that D-10-Z _1d was used instead of using D-1-Z _1d . The photoelectric conversion characteristics of the produced photoelectric conversion elements were measured by the same method as in Example 6, and are summarized in Table 1.

In Example 6, a photoelectric conversion element was produced in the same manner as in Example 6 except that D-19-Z _1d was used instead of using D-1-Z _1d . The photoelectric conversion characteristics of the produced photoelectric conversion elements were measured by the same method as in Example 6, and are summarized in Table 1.

The adsorption amount of D-1-Z _{1d to} the semiconductor fine particle electrode substrate was calculated by the following method.
First, the semiconductor fine particle electrode substrate prepared in (J2) of Example 6 was immersed in an ethanol solution of D-1-Z _1d (3 × 10 ⁻⁴ mol / L) for 15 hours, and was not put on the semiconductor fine particle electrode substrate. The adsorbed D-1-Z _1d was washed away with ethanol and then dried to produce a semiconductor fine particle electrode substrate on which D-1-Z _1d was adsorbed.

Next, the semiconductor fine particle electrode substrate on which D-1-Z _1d was adsorbed was immersed in 10 mL of a 1N aqueous sodium hydroxide solution, and D-1-Z _1d was detached from the semiconductor fine particle electrode substrate. After the pH of the aqueous solution from which D-1-Z _1d was desorbed was adjusted to pH 2 with 1N hydrochloric acid, water was removed from the aqueous solution, and D-1-Z _1d adsorbed on the semiconductor fine particle electrode substrate was removed. Obtained. D-1-Z _1d adsorbed on the semiconductor fine particle electrode substrate is dissolved in 100 mL of ethanol, and the absorbance at the maximum absorption wavelength (hereinafter referred to as “Shimadzu UV-2550, measurement optical path length 1 cm”) is used. (Abbreviated as ABS).

Furthermore, using this spectrophotometer, the molar extinction coefficient (unit: [L / mol x cm], hereinafter abbreviated as E) of D-1-Z _1d at the maximum absorption wavelength in ethanol was measured. .
The amount of adsorption of D-1-Z _1d per square centimeter of the semiconductor fine particle electrode substrate (unit: [mol / cm ² ], hereinafter abbreviated as P) is expressed by the formula (P-1 ).
P = ABS ÷ E ÷ 10 formulas (P-1)
Table 2 summarizes the adsorption amount of D-1-Z _1d calculated using the formula (P-1) onto the semiconductor fine particle electrode substrate.

(Comparative Example 1)
Instead of using D-1-Z _1d in Example 6, a photoelectric conversion element was prepared in the same manner as in Example 6 except that the comparative compound (DN) was used, and the photoelectric conversion characteristics were measured. The results are summarized in Table 1.

(Comparative Example 2)
Instead of using D-1-Z _1d in Example 6, the photoelectric conversion element was operated in the same manner as in Example 6 except that the following comparative compound (DM) described in JP-A-2003-78152 was used. The photoelectric conversion characteristics were measured and summarized in Table 1.

表１より明らかなように、本発明の光電変換素子用材料を用いた光電変換素子は、比較化合物（Ｄ−Ｎ）および比較化合物（Ｄ−Ｍ）を用いた光電変換素子の光電変換特性と比
較して、良好かつ実用的な値を示した。また、実施例６〜１０の光電変換特性の測定中、光電変換特性の値に変化は見られなかった。一方で、比較例１および２の光電変換素子は、短絡電流密度の値においてそれぞれ初期値の１０％および１５％の低下が観測された。以上の結果より本発明の化合物を用いた光電変換素子は、比較化合物（Ｄ−Ｎ）および比較化合物（Ｄ−Ｍ）を用いた光電変換素子に対して、耐久性も良好であった。

As is clear from Table 1, the photoelectric conversion element using the photoelectric conversion element material of the present invention has the photoelectric conversion characteristics of the photoelectric conversion element using the comparative compound (DN) and the comparative compound (DM). In comparison, good and practical values were shown. Moreover, the change in the value of the photoelectric conversion characteristic was not seen during the measurement of the photoelectric conversion characteristic of Examples 6-10. On the other hand, in the photoelectric conversion elements of Comparative Examples 1 and 2, a decrease of 10% and 15% of the initial value was observed in the value of the short circuit current density, respectively. From the above results, the photoelectric conversion element using the compound of the present invention was also more durable than the photoelectric conversion element using the comparative compound (DN) and the comparative compound (DM).

また、表２から明らかなように、本発明の光電変換素子用材料は、比較化合物（Ｄ−Ｎ）に対して、半導体微粒子電極基板への吸着性能が良好であることがわかる。 (Comparative Example 3)
In Example 11, instead of using D-1-Z _1d , the adsorption amount to the semiconductor fine particle electrode substrate was calculated in the same manner as in Example 11 except that the comparative compound (DN) was used. Summarized in

Further, as is clear from Table 2, it can be seen that the material for a photoelectric conversion element of the present invention has good adsorption performance to the semiconductor fine particle electrode substrate with respect to the comparative compound (DN).

  The photoelectric conversion element using the photoelectric conversion element material of the present invention can be used as an element such as a solar cell, for example.

It is a fragmentary sectional view showing the structure of the preferable photoelectric conversion element of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 ... Substrate 3, 4 ... Conductive layer 5 ... Dye adsorption semiconductor fine particle layer 6 ... Charge transfer layer

Claims (9)

A photoelectric conversion element material represented by the following general formula (1).

[Wherein, ring A and ring B represent a heterocyclic ring, n1 is 1 or 2, and R _{1 to} R ₃ represent a hydrogen atom, a hydrocarbon group, a heterocyclic group, a halogen atom, or a general formula (2) The group shown is represented, and at least one of R _{1 to} R ₃ is a group represented by the following general formula (2). ]

[Wherein, ring C represents an aromatic ring or a heterocyclic ring, and R ₄ and R ₅ represent a carboxyl group, a hydroxyl group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, a silicic acid group, a boric acid group and their protons. It is a group having at least one selected from the group consisting of dissociators. ] The photoelectric conversion element material according to claim 1, wherein the photoelectric conversion element material represented by the general formula (1) is represented by the following general formula (3), general formula (4), or general formula (5).

[In General Formulas (3) to (5), R _{1 to} R ₃ and n1 are the same groups as in General Formula (1), and at least one of R _{1 to} R ₃ is represented by General Formula (2). R _{6 to} R ₁₆ represent a hydrocarbon group, a nitrogen-containing functional group, an oxygen-containing functional group, a sulfur-containing functional group, a heterocyclic group, or a halogen atom, and a ₁ to a ₅ are 0 to 4 Represents an integer, and when a ₁ to a ₅ are 2 or more, a plurality of R _{6 to} R ₁₀ on the same aromatic ring may be the same or different, and may be connected to each other to form a ring, and Q ₁ to Q ₄ represents an alkylene group, -N (R) - (R represents an alkyl group), an oxygen atom, a sulfur atom or a selenium atom, Z is versus when necessary counterions to neutralize the charge Represents an ion. ] The photoelectric conversion element material according to claim 2, wherein R ₂ is represented by the general formula (2) in the general formulas (3) to (5). The photoelectric conversion element formed using the material for photoelectric conversion elements of any one of Claims 1-3. The photoelectric conversion element of Claim 4 using the electrode which couple | bonded and / or adsorb | sucked the photoelectric conversion element material of any one of Claims 1-3 to the semiconductor fine particle. A cyanine compound represented by the following general formula (6).

[In General Formula (6), Rings C, R ₄ and R ₅ are the same as in General Formula (2), and R ₆ , R ₇ , R ₁₁ , R ₁₂ , a ₁ , a ₂ , Q ₁ , Q ₂ and Z are the same as those in the general formula (3). ] The cyanine compound according to claim 6, wherein ring C is represented by the following general formula (7).

[In General Formula (7), R ₂₁ represents a hydrocarbon group, a nitrogen-containing functional group, an oxygen-containing functional group, a sulfur-containing functional group, a heterocyclic group, or a halogen atom, and a ₂₁ represents an integer of 0 to 4, * Represents the position of the linking group of the ring. ]   The material for a photoelectric conversion element according to claim 1, wherein the compound represented by the general formula (1) is the cyanine compound according to claim 6 or 7.   The photoelectric conversion element formed using the material for photoelectric conversion elements of Claim 8.

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