JP2011222373A - Dye-sensitized type photoelectric conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric conversion element which is inexpensive and superior in conversion efficiency, and to provide a solar cell.SOLUTION: A dye represented by formula (1), or a salt thereof is carried by a thin film of oxide semiconductor particulates. (where Xto Xeach represents oxygen, sulfur or selenium, and Rto Rrepresent hydrogen, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, halogen, an amino group, an alkoxyl group or a specified structural formula.)

Description

  The present invention relates to a photoelectric conversion element having a thin film of semiconductor fine particles sensitized with a dye or a salt thereof and a solar cell using the same, and more particularly, to a photoelectric conversion element in which a dye having a specific structure is supported on a thin film of oxide semiconductor fine particles. The present invention relates to a conversion element and a solar cell using the same.

  Solar cells that use sunlight as an energy resource to replace fossil fuels such as oil and coal are drawing attention. Currently, active studies are being made on silicon solar cells using crystalline or amorphous silicon, or compound semiconductor solar cells using gallium, arsenic, or the like. However, since they require high energy and cost for production, they are difficult to use for general purposes. A photoelectric conversion element using semiconductor fine particles sensitized with a dye or a solar cell using the same is also known, and materials and manufacturing techniques for producing the photoelectric conversion element are disclosed (Patent Document 1, Non-Patent Document 1). Non-patent document 2). Since this photoelectric conversion element is manufactured using a relatively inexpensive oxide semiconductor such as titanium oxide, there is a possibility that a photoelectric conversion element having a lower cost than a conventional solar cell using silicon or the like may be obtained. It has attracted attention due to the fact that colorful solar cells can be obtained. However, the problem that conversion efficiency is low compared with a silicon solar cell remains, and the further improvement of conversion efficiency is desired (refer patent document 1).

Japanese Patent No. 2664194

B. O'Regan et al., Nature, 353, 737 (1991) M.M. K. Nazeeruddin et al., J. MoI. Am. Chem. Soc. 115, 6382 (1993) W. Kubo et al., Chem. Lett. , 1241 (1998)

  In photoelectric conversion elements using oxide semiconductor fine particles sensitized with a dye, development of stable, high conversion efficiency, and high practicality is required.

  As a result of diligent efforts to solve the above-mentioned problems, the present inventors can sensitize a thin film of semiconductor fine particles using a dye having a specific structure, and the above-mentioned problems can be solved by creating a photoelectric conversion element. As a result, the present invention has been completed.

That is, the present invention
(1) A photoelectric conversion element in which a dye represented by the following formula (1) or a salt thereof is supported on a thin film of oxide semiconductor fine particles provided on a substrate,

(In formula (1), X _{1 to} X ₃ each represents an oxygen atom, a sulfur atom or a selenium atom. R _{1 to} R ₆ each independently represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom. An atom, an amino group, an alkoxyl group or the following formula (2) is represented, and at least one of R _{1 to} R ₆ is the following formula (2).

(In Formula (2), Y ₁ and Z ₁ each independently represent a hydrogen atom, a carboxyl group, a cyano group, or a phosphoric acid group. Q ₁ represents an oxygen atom, a sulfur atom, or a selenium atom. A _{1 to} A ₃ Each independently represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, m1 represents an integer of 0 to 16. In formula (2), * represents a formula ( 1) represents the bonding position of R _{1 to} R ₆ .
(2) R ₁ is represented by the formula (2), and R _{2 to} R ₆ are each independently a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom, an amino group, or an alkoxyl group ( 1) The photoelectric conversion element according to
(3) The photoelectric conversion element according to the above item (2), wherein Q ₁ is a sulfur atom,
(4) The photoelectric conversion device according to (3), wherein R ₁ is represented by the following formula (3):

(In the formula (3), A ₁ , Y ₁ and Z ₁ represent the same meaning as in the formula (2) described in the preceding item (1). A _{4 to} A ₁₁ are a hydrogen atom and an aliphatic hydrocarbon group, respectively. Represents an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, n1 represents an integer of 0 to 4. * represents the bonding position of R _{1 in} formula (1).
(5) The photoelectric conversion device according to the above item (4), wherein A ₅ and A ₁₀ are aliphatic hydrocarbon groups,
(6) The photoelectric conversion device according to (5), wherein A ₅ and A ₁₀ are n-hexyl groups,
(7) The photoelectric conversion element according to any one of (4) to (6), wherein A ₄ , A _{6 to} A ₉ and A ₁₁ are all hydrogen atoms.
(8) The photoelectric conversion element according to any one of (4) to (7), wherein n1 is an integer of 0 to 2.
(9) Any one of (2) to (8), wherein R ₂ , R ₄ and R ₆ are all hydrogen atoms, and R ₃ and R ₅ are each independently a hydrogen atom or an aromatic hydrocarbon group. The photoelectric conversion element according to item,
(10) The photoelectric conversion element according to the above item (9), wherein both R ₃ and R ₅ are represented by the following formula (4):

(In formula (4), * represents the bonding position with R ₃ and R _{5 in} formula (1).)
(11) The photoelectric conversion element according to any one of (1) to (10), wherein X _{1 to} X ₃ are all sulfur atoms,
(12) The photoelectric conversion element according to any one of (1) to (11), wherein at least _one of Y ₁ and Z ₁ is a carboxyl group,
(13) The photoelectric conversion element according to (12), wherein any _one of Y ₁ and Z ₁ is a carboxyl group and the other is a cyano group,
(14) The photoelectric conversion device according to the above item (13), wherein Y ₁ is a carboxyl group and Z ₁ is a cyano group,
(15) The photoelectric conversion element according to any one of (1) to (14), wherein A ₁ is a hydrogen atom,
(16) The photoelectric conversion element according to the above item (1), wherein the dye represented by the formula (1) or a salt thereof is any one of the following formulas (7) to (10):

(17) A solar cell using the photoelectric conversion element according to any one of (1) to (16),
(18) A dye or a salt thereof represented by the formula (1) described in (1) above,
(19) The present invention relates to a dye represented by the formulas (7) to (10) or a salt thereof described in (16) above.

  By using the dye of the present invention having a specific structure or a salt thereof, a photoelectric conversion element and a solar cell having high conversion efficiency and high stability can be provided.

It is a schematic diagram of the cell of a dye-sensitized photoelectric conversion element.

The present invention is described in detail below.
The photoelectric conversion element of the present invention is obtained by supporting a dye (including a salt thereof) represented by the following formula (1) on a thin film of oxide semiconductor fine particles provided on a substrate. In the present specification, the “compound” represents a compound or a salt thereof unless otherwise specified.

In the formula (1), X _{1 to} X ₃ each independently represent an oxygen atom, a sulfur atom or a selenium atom, and all are preferably sulfur atoms.

In the formula (1), R _{1 to} R ₆ each independently represent a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom, an amino group, an alkoxyl group, or a formula (2) described later, and R ₁ At least one of R ₆ to R ₆ is the following formula (2).

Examples of the aliphatic hydrocarbon group for R _{1 to} R ₆ in the formula (1) include a saturated or unsaturated linear, branched or cyclic alkyl group which may have a substituent. A saturated or unsaturated linear or branched alkyl group having 1 to 36 carbon atoms that may have is preferable, and a saturated or unsaturated linear chain having 1 to 18 carbon atoms that may have a substituent. Alternatively, a branched alkyl group is more preferable. Examples of the cyclic alkyl group which may have a substituent include cycloalkyl having 3 to 8 carbon atoms. Specific examples of the aliphatic hydrocarbon group include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, t-butyl group, octyl group, octadecyl group, Cyclohexyl group, vinyl group, propenyl group, pentynyl group, butenyl group, hexenyl group, hexadienyl group, isopropenyl group, isohexenyl group, cyclohexenyl group, cyclopentadienyl group, ethynyl group, propynyl group, pentynyl group, A hexynyl group, an isohexynyl group, a cyclohexynyl group, etc. are mentioned. These may have a substituent as described above. Examples of the substituent that the aliphatic hydrocarbon group may have include, for example, an aromatic hydrocarbon group that may have a substituent, an aliphatic hydrocarbon group that may have a substituent, hydroxyl Group, phosphate group, cyano group, nitro group, halogen atom, carboxyl group, carbonamido group, alkoxycarbonyl group, arylcarbonyl group, alkoxyl group, aryloxy group, substituted amide group, acyl group and optionally substituted An amino group etc. are mentioned.

The aromatic hydrocarbon group mentioned as the substituent that the aliphatic hydrocarbon group may have is the same as the aromatic hydrocarbon group in R _{1 to} R ₆ described later, As the aliphatic hydrocarbon group mentioned as the substituent that the aromatic hydrocarbon group may have, the same aliphatic hydrocarbon group as the aliphatic hydrocarbon group mentioned in the description of R _{1 to} R ₆ above Is mentioned. Examples of the alkoxycarbonyl group exemplified as the substituent that the aliphatic hydrocarbon group may have include an alkoxycarbonyl group having 1 to 10 carbon atoms, and specific examples thereof include methoxycarbonyl and ethoxycarbonyl. , N-propoxycarbonyl, isopropoxycarbonyl, n-butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl, t-butoxycarbonyl, n-pentoxycarbonyl, n-hexyloxycarbonyl, n-heptyloxycarbonyl, n-nonyl Examples include oxycarbonyl and n-decyloxycarbonyl. Examples of the arylcarbonyl group exemplified as the substituent that the aliphatic hydrocarbon group may have include an arylcarbonyl group in which the above aromatic hydrocarbon group and carbonyl group are bonded, and the like. Examples include phenylcarbonyl, naphthocarbonyl and the like. Examples of the aryloxy group exemplified as the substituent that the aliphatic hydrocarbon group may have include, for example, an aryloxy group in which an aromatic hydrocarbon group and an oxidation atom in R _{1 to} R ₆ described later are bonded to each other. Specific examples thereof include a phenoxy group and a naphthoxy group.

  Examples of the substituted amide group exemplified as the substituent that the aliphatic hydrocarbon group may have include an amide, an acetamide, an alkylamide, and an arylamide group, and specifically preferred are amide, acetamide, N -Methylamide, N-ethylamide, N- (n-propyl) amide, N- (n-butyl) amide, N-isobutyramide, N- (sec-butylamide), N- (t-butyl) amide, N, N -Dimethylamide, N, N-diethylamide, N, N-di (n-propyl) amide, N, N-di (n-butyl) amide, N, N-diisobutyramide, N-methylacetamide, N-ethylacetamide N- (n-propyl) acetamide, N- (n-butyl) acetamide, N-isobutylacetamide, N- (sec-butyl) Acetamide, N- (t-butyl) acetamide, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-di (n-propyl) acetamide, N, N-di (n-butyl) acetamide, N , N-diisobutylacetamide, phenylamide, naphthylamide, phenylacetamide, naphthylacetamide and the like. Examples of the acyl group exemplified as the substituent that the aliphatic hydrocarbon group may have include an alkylcarbonyl group having 1 to 10 carbon atoms, an arylcarbonyl group, and the like, and preferably 1 to 4 carbon atoms. Examples of the alkylcarbonyl group include acetyl, propionyl, trifluoromethylcarbonyl, pentafluoroethylcarbonyl, benzoyl, naphthoyl and the like.

The aromatic hydrocarbon group in R _{1 to} R ₆ in the formula (1) means a group obtained by removing one hydrogen atom from an aromatic ring. Specific examples of the aromatic ring include benzene, naphthalene, anthracene, phenanthrene, Aromatic hydrocarbon rings such as pyrene, perylene, terylene, fluorene, biphenyl, terphenyl, polythiophenes such as thiophene, bithiophene, terthiophene, tetrathiophene, indene, azulene, pyridine, pyrazine, pyrimidine, pyrazole, pyrazolidine, thiazolidine, oxazolidine , Pyran, chromene, pyrrole, pyrrolidine, benzimidazole, imidazoline, imidazolidine, imidazole, pyrazole, triazole, triazine, diazole, indoline, thienothiophene, furan, oxazole, oxadiazole Heteroaromatic rings such as thiazine, thiazole, indole, benzothiazole, benzothiadiazole, naphthothiazole, benzoxazole, naphthoxazole, indolenine, benzoindolenine, pyrazine, quinoline, quinazoline, condensed aromatic rings such as fluorene, carbazole, etc. Polythiophene such as thiophene, bithiophene, terthiophene, and tetrathiophene is preferable, and tetrathiophene is more preferable. These aromatic hydrocarbon groups may have a substituent.

  Examples of the substituent that the aromatic hydrocarbon group may have include the above-described aliphatic hydrocarbon group and halogen atom, and the like, depending on the purpose such as solubility in a solvent, molecular structure control, battery performance and the like. It can be selected as appropriate. A saturated alkyl group having 1 to 36 carbon atoms is particularly preferable. The saturated alkyl group may be the same as that mentioned for the above-mentioned aliphatic hydrocarbon group.

Examples of the halogen atom in R _{1 to} R ₆ in Formula (1) include a fluorine atom, a chlorine atom, a bromine, and an iodine atom.

Examples of the amino group in R _{1 to} R ₆ of the formula (1) include an amino group, a mono- or dimethylamino group, a mono- or diethylamino group, a mono- or di (n-propyl) amino group, and a mono- or di (n-butyl). Alkyl-substituted amino groups such as amino groups, mono- or di (n-hexyl) amino groups, aromatic-substituted amino groups such as mono- or diphenylamino groups, mono- or dinaphthylamino groups, and alkyl groups such as monoalkylmonophenylamino groups And an amino group or a benzylamino group substituted by one aromatic hydrocarbon residue, an acetylamino group, a phenylacetylamino group, and the like.

The alkoxyl group in R _{1 to} R ₆ in the formula (1) represents, for example, a group in which an oxygen atom is bonded to the above-described aliphatic hydrocarbon group, and specifically includes a methoxy group, an ethoxy group, and an n-propoxy group. , Isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group and the like. These alkoxyl groups may have the same substituent as those exemplified as the substituent that the aliphatic hydrocarbon group in R _{1 to} R ₆ may have.

In formula (1), at least one of R _{1 to} R ₆ represents the following formula (2). R ₁ is the formula (2), and R _{2 to} R ₆ are preferably each independently a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom, an amino group, or an alkoxyl group, More preferably, R ₂ , R ₄ and R ₆ are all hydrogen atoms, and R ₃ and R ₅ are each independently a hydrogen atom or an aromatic hydrocarbon group, and R ₂ , R ₄ and R ₆ are any Is more preferably a hydrogen atom, and R ₃ and R ₅ are each more preferably the following formula (4).

In formula (4), * represents the position where R ₃ and R _{5 in} formula (1) are bonded.

In formula (2), Q ₁ represents an oxygen atom, a sulfur atom or a selenium atom, and is preferably a sulfur atom.

In formula (2), A ₂ and A ₃ each independently represent a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom or an alkoxyl group. Examples of the aliphatic hydrocarbon group, aromatic hydrocarbon group, halogen atom and alkoxyl group in A ₂ and A ₃ are the same as those in R _{1 to} R ₆ .

  In the formula (2), m1 represents an integer of 0 to 16, and is preferably an integer of 0 to 4.

In formula (2), * represents the position at which R _{1 to} R _{6 in} formula (1) are bonded.

More preferably, R ₁ in the formula (1) is the following formula (3).

In Formula (2) and Formula (3), A ₁ represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, and is preferably a hydrogen atom. As the aliphatic hydrocarbon group, aromatic hydrocarbon group, halogen atom or alkoxyl group for A _1, the same groups as those described above for R _{1 to} R ₆ can be mentioned.

In Formula (2) and Formula (3), Y ₁ and Z ₁ each represent a hydrogen atom, a carboxyl group, a cyano group, or a phosphate group, and are preferably a carboxyl group or a cyano group, and Y ₁ and Z ₁ It is more preferred that at least one of them is a carboxyl group, and it is more preferred that any _one of Y ₁ and Z ₁ is a carboxyl group and the other is a cyano group, Y ₁ is a carboxyl group, and Z ₁ Is most preferably a cyano group.

In formula (3), A _{4 to} A ₁₁ each represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, and A ₄ , A _{6 to} A ₉ and A ₁₁ are all A hydrogen atom is preferred. A ₅ and A ₁₀ are preferably aliphatic hydrocarbon groups, more preferably n-hexyl groups, A ₄ , A _{6 to} A ₉ and A ₁₁ are all hydrogen atoms, and More preferably, A ₅ and A ₁₀ are both aliphatic hydrocarbon groups, A ₄ , A _{6 to} A ₉ and A ₁₁ are hydrogen atoms, and A ₅ and A ₁₀ are n-hexyl groups. Most preferred.
Examples of the aliphatic hydrocarbon group, aromatic hydrocarbon group, halogen atom or alkoxyl group in A _{4 to} A ₁₁ are the same as those in R _{1 to} R ₆ .

  In formula (3), n1 represents an integer of 0 to 4, and is preferably an integer of 0 to 2.

  When the dye represented by the formula (1) has an acidic group such as a carboxyl group, a phosphate group, a hydroxyl group, or a sulfonic acid group as a substituent, the dye may form a salt. For example, salts of alkali metals or alkaline earth metals such as lithium, sodium, potassium, magnesium and calcium, or organic bases such as quaternary ammonium such as tetramethylammonium, tetrabutylammonium, pyridinium, imidazolium, piperazinium and piperidinium Of the salt. Preference is given to tetrabutylammonium salts and piperidinium salts. The purpose of forming the salt mainly includes improvement of photoelectric conversion efficiency, control of solubility in a solvent, stability of a compound or easiness of synthesis and purification.

  The dye represented by the formula (1) or a salt thereof can take a structural isomer such as a cis isomer, a trans isomer and a mixture thereof, an optically active isomer, and a racemate, but any isomer is not particularly limited in the present invention. It can be used satisfactorily as a photosensitizing dye, and each isomer may be used alone or as a mixture comprising a plurality.

Examples of the dye represented by the formula (1) or a salt thereof include X _{1 to} X ₃ and R _{1 to} R ₆ of the above formula (1), Y ₁ , Z ₁ , Q ₁ , A _{1 to of} the formula (2). A dye or a salt thereof in which A ₃ and m ₁ , A ₁ , Y ₁ , Z ₁ , A _{4 to} A ₁₁ and n 1 in Formula (3) are preferably combined, or a salt thereof is particularly preferable. ) To (10) or a salt thereof.

  The dyes represented by the formulas (7) to (10) can be produced, for example, by the following reaction pathway, but the dyes included in the formula (1) other than the formulas (7) to (10) are also included. It can manufacture according to these reaction pathways.

  Specific examples of the dye represented by the formula (1) are shown using the following general formula (1000) and shown in Table 1. In the table, TPA represents triphenylamine.

  In the dye-sensitized photoelectric conversion element of the present invention, for example, a thin film of oxide semiconductor fine particles is provided on a substrate, and then the dye of formula (1) is supported on the thin film.

As a substrate on which a thin film of oxide semiconductor fine particles is provided, a substrate having a conductive surface is preferable, but such a substrate is easily available in the market. Specifically, for example, conductive metal oxide such as tin oxide doped with indium, fluorine, antimony or copper on the surface of glass or the surface of a transparent polymer material such as polyethylene terephthalate or polyether sulfone, copper, What provided the thin film of metals, such as silver and gold | metal | money, can be used. The conductivity is usually 1000Ω or less, and particularly preferably 100Ω or less.
The oxide semiconductor fine particles are preferably metal oxides, and specific examples thereof include oxides of titanium, tin, zinc, tungsten, zirconium, gallium, indium, yttrium, niobium, tantalum, vanadium, and the like. Of these, oxides such as titanium, tin, zinc, niobium, and indium are preferable, and titanium oxide, zinc oxide, and tin oxide are more preferable. These oxide semiconductors can be used alone, but can also be mixed or used by coating the surface of the semiconductor. The average particle diameter of the oxide semiconductor fine particles is usually 1 to 500 nm, preferably 1 to 100 nm. The oxide semiconductor fine particles may be mixed with a large particle size and a small particle size, or may be used in multiple layers.

  The thin film of oxide semiconductor fine particles is a method of directly applying oxide semiconductor fine particles on a substrate by spray spraying, a method of electrically depositing semiconductor fine particles in a thin film form using the substrate as an electrode, a slurry of semiconductor fine particles or a semiconductor alkoxide, etc. After the paste containing the fine particles obtained by hydrolyzing the precursor of the semiconductor fine particles is applied on the substrate, it can be formed on the substrate by a method such as drying, curing or baking. In view of the performance of the electrode using an oxide semiconductor, a method using a slurry is preferable. In the case of this method, the slurry is obtained by dispersing the secondary agglomerated oxide semiconductor fine particles in a dispersion medium by an ordinary method so that the average primary particle diameter is 1 to 200 nm.

  The dispersion medium for dispersing the slurry is not particularly limited as long as the semiconductor fine particles can be dispersed. Water, alcohols such as ethanol, ketones such as acetone and acetylacetone, hydrocarbons such as hexane, and the like are used. A mixture may be used, and the use of water is preferable in that the viscosity change of the slurry is reduced. A dispersion stabilizer can be used for the purpose of stabilizing the dispersion state of the oxide semiconductor fine particles. Examples of the dispersion stabilizer that can be used include acids such as acetic acid, hydrochloric acid, and nitric acid, and organic solvents such as acetylacetone, acrylic acid, polyethylene glycol, and polyvinyl alcohol.

  The substrate coated with the slurry may be fired, and the firing temperature is usually 100 ° C. or higher, preferably 200 ° C. or higher, and the upper limit is generally lower than the melting point (softening point) of the substrate, and the upper limit is usually 900 ° C. The temperature is preferably 600 ° C. or lower. The firing time is not particularly limited, but is preferably within 4 hours. The thickness of the thin film of oxide semiconductor fine particles on the substrate is usually 1 to 200 μm, preferably 1 to 50 μm.

A secondary treatment may be applied to the thin film of oxide semiconductor fine particles. For example, semiconductor fine particles are immersed in the same metal alkoxide, metal acyloxide, chloride, nitride, sulfide, etc. as the semiconductor directly by dipping the whole substrate provided with a thin film of oxide semiconductor fine particles and drying or refiring. The performance of the thin film can also be improved. Examples of the metal alkoxide include titanium ethoxide, titanium isopropoxide, and titanium t-butoxide, and examples of the metal acyloxide include n-dibutyl-diacetyltin, and alcohol solutions thereof are used. Examples of the chloride include titanium tetrachloride, tin tetrachloride, zinc chloride and the like, and an aqueous solution thereof is used.
The oxide semiconductor thin film thus obtained is composed of fine particles of an oxide semiconductor.

Next, a method for supporting the dye represented by the formula (1) of the present invention on a thin film of oxide semiconductor fine particles will be described.
As a method for supporting the dye of the formula (1), a solution obtained by dissolving the dye in a solvent capable of dissolving the dye, or a dispersion obtained by dispersing the dye in the case of a dye having low solubility And a method of immersing a substrate provided with a thin film of the oxide semiconductor fine particles. The concentration in the solution or dispersion is appropriately determined depending on the dye. A thin film of semiconductor fine particles formed on the substrate is immersed in the solution or dispersion. The immersion temperature is generally from room temperature to the boiling point of the solvent, and the immersion time is about 1 minute to 48 hours. Specific examples of the solvent that can be used for dissolving the dye include methanol, ethanol, acetonitrile, dimethyl sulfoxide, dimethylformamide, acetone, t-butanol, chloroform, dichloromethane, n-hexane, tetrahydrofuran, water and the like. . These solvents may be used as a mixture of two or more in any ratio. Moreover, when the pigment | dye of Formula (1) does not show sufficient solubility with respect to these solvents, ammonium salts, such as tetrabutylammonium iodide, can be added and the dissolution of a pigment | dye can also be accelerated | stimulated. The dye density | concentration in a solution is 1 * 10 < ^-6 > M-1M normally, Preferably it is 1 * 10 < ^-5 > M-1 * 10 < ^-1 > M. Thus, the photoelectric conversion element of the present invention having a thin film of oxide semiconductor fine particles sensitized with the dye of formula (1) is obtained.

  The dye of the formula (1) to be carried may be one kind or a plurality of kinds may be mixed. Moreover, when mixing, the pigment | dye of Formula (1) of this invention may be sufficient, and another pigment | dye and a metal complex pigment | dye may be mixed. In particular, by mixing dyes having different absorption wavelengths, a wide absorption wavelength can be used, so that a solar cell with high conversion efficiency can be obtained. When two or more dyes are used, the dyes may be adsorbed sequentially on the thin film of semiconductor fine particles, or may be admixed and dissolved.

  There are no particular limitations on the ratio of the dyes to be mixed, and optimization conditions are appropriately selected from the respective dyes. Generally, it is preferable to use at least about 10% mol or more per dye from mixing in equimolar amounts. . When a dye is adsorbed to a thin film of oxide semiconductor fine particles using a solution in which two or more kinds of dyes are dissolved or dispersed, the total concentration of the dye in the solution may be the same as when only one kind is supported. As the solvent in the case of using a mixture of dyes, the above-mentioned solvents can be used, and the solvents for the respective dyes to be used may be the same or different.

  When the dye is supported on the thin film of oxide semiconductor fine particles, it is effective to support the dye in the coexistence of the inclusion compound in order to prevent the association between the dyes. Examples of the inclusion compound include steroidal compounds such as cholic acid, crown ether, cyclodextrin, calixarene, polyethylene oxide, and the like. Deoxycholic acid, dehydrodeoxycholic acid, chenodeoxycholic acid, ursodeoxycholic are preferable. Examples include acids, cholic acid methyl esters, cholic acids such as sodium cholate, and polyethylene oxide. Alternatively, after the dye is supported, the thin film of semiconductor fine particles may be treated with an amine compound such as 4-t-butylpyridine (TBP). As a treatment method, for example, a method of immersing a substrate provided with a thin film of semiconductor fine particles carrying a dye in an ethanol solution of amine is employed.

  The solar cell of the present invention is composed of a photoelectric conversion element electrode in which a dye is supported on the oxide semiconductor fine particle thin film, a counter electrode, a redox electrolyte, a hole transport material, a p-type semiconductor, or the like. Examples of the redox electrolyte, hole transport material, and p-type semiconductor include liquids, solidified bodies (gel and gel), and solids. Liquids such as redox electrolytes, molten salts, hole transport materials, p-type semiconductors, etc., dissolved in solvents and room temperature molten salts are solidified (gels and gels). Examples include a matrix and a low molecular gelling agent. As a solid material, a redox electrolyte, a molten salt, a hole transport material, a p-type semiconductor, or the like can be used. Examples of the hole transport material include amine derivatives, conductive polymers such as polyacetylene, polyaniline, and polythiophene, and materials used for discotic liquid crystal phases such as triphenylene compounds. Examples of the p-type semiconductor include CuI and CuSCN.

  The counter electrode is preferably conductive and has a catalytic action on the reduction reaction of the redox electrolyte. For example, a glass or polymer film deposited with platinum, carbon, rhodium, ruthenium or the like, or a film coated with conductive fine particles can be used.

The redox electrolyte used in the solar cell of the present invention includes a halogen redox electrolyte composed of a halogen compound and a halogen molecule having a halogen ion as a counter ion, ferrocyanate-ferricyanate, ferrocene-ferricinium ion, cobalt complex Examples thereof include metal redox electrolytes such as metal complexes, and organic redox electrolytes such as alkylthiol-alkyldisulfides, viologen dyes, hydroquinone-quinones, and the like, but halogen redox electrolytes are preferred. Examples of the halogen molecule in the halogen redox electrolyte comprising a halogen compound-halogen molecule include iodine molecule and bromine molecule, and iodine molecule is preferable. As the halogen compound having a halogen ion as a counter ion, for example LiBr, NaBr, KBr, LiI, NaI, KI, CsI, CaI 2, MgI 2, CuI and halogenated metal salt or tetraalkylammonium iodide, and imidazolium Examples include halogen organic quaternary ammonium salts such as rhodium iodide and pyridinium iodide, and salts having iodine ions as counter ions are preferred. Moreover, it is also preferable to use the electrolyte which uses imide ions, such as a bis (trifluoromethanesulfonyl) imide ion and a dicyano imide ion, as a counter ion other than the said iodine ion.

  When the redox electrolyte is constituted in the form of a solution containing the redox electrolyte, an electrochemically inert solvent is used as the solvent. For example, acetonitrile, propylene carbonate, ethylene carbonate, 3-methoxypropionitrile, methoxyacetonitrile, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, γ-butyrolactone, dimethoxyethane, diethyl carbonate, diethyl ether, diethyl carbonate, dimethyl carbonate, 1,2-dimethoxyethane, dimethylformamide, dimethyl sulfoxide, 1,3-dioxolane, methyl formate, 2-methyltetrahydrofuran, 3-methyl-oxazolidin-2-one, sulfolane, tetrahydrofuran, water and the like. Among them, in particular, acetonitrile, propylene carbonate, ethylene carbonate, 3-methoxypropioni Lil, methoxy acetonitrile, ethylene glycol, 3-methyl - oxazolidin-2-one, .gamma.-butyrolactone and the like are preferable. You may use these individually or in combination of 2 or more types. In the case of a gel electrolyte, an electrolyte or an electrolyte solution contained in a matrix such as an oligomer or a polymer, or a low-molecular gelling agent described in Non-Patent Document 3 that also contains an electrolyte or an electrolyte solution, etc. Is mentioned. The density | concentration of a redox electrolyte is 0.01-99 mass% normally, Preferably it is about 0.1-90 mass%.

  In the solar cell of the present invention, a counter electrode is disposed between electrodes of a photoelectric conversion element in which a dye of the formula (1) of the present invention is supported on a thin film of oxide semiconductor fine particles on a substrate, and a redox electrolyte is interposed therebetween. It is obtained by filling a solution containing the like.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.
The absorption spectrum is Shimadzu Magnetospectrophotometer UV-3100 (P / N206-13500, manufactured by Shimadzu Corporation), the nuclear magnetic resonance analysis is LAMBER-NMR (400 MHz, 270 MHz) (manufactured by JEOL Ltd.), and the mass analysis is Shimadzu GCMS. Elemental analysis was performed with a Parkin Elmer 2400 type elemental analyzer using a QP5050A type mass spectrometer (manufactured by Shimadzu Corporation) and MALDI-MS KRATOS ANALYTICAL KOMACT (manufactured by Shimadzu Corporation).

Synthesis example 1
10.0 g of 1,3,5-trichlorobenzene and 80.6 g of iodine were stirred in 125 ml of concentrated sulfuric acid at 125 to 135 ° C. for 48 hours, and after completion of the reaction, the reaction solution was added to ice. The produced solid crystals were collected by filtration and washed with 400 ml of an aqueous sodium bisulfide solution, 400 ml of water and 100 ml of ethanol, and then recrystallized with tetrahydrofuran (THF) to obtain 22.1 g of the compound (2001) as white needle crystals. .
The mass spectrum of the obtained compound (2001) was as follows.
MS (EI) m / z; 558 (M +)

Synthesis example 2
Compound (2001) obtained by dissolving 2.94 g of 3-methyl-1-butyn-3-ol, 560 mg of Pd (PPh ₃ ) ₂ Cl ₂ , 4.2 ml of diisopropylamine, and 307 mg of CuI in 45 ml of toluene under a nitrogen atmosphere. 0 g solution was added and allowed to react. After the reaction solution was refluxed for 22 hours, water was added to the reaction solution and extracted with chloroform (100 ml × 3). The chloroform phase was washed with saturated brine (100 ml × 3), dried over magnesium sulfate, magnesium sulfate was removed, and then the solvent was distilled off to obtain a crude product. The obtained crude product was washed with benzene and cold toluene to obtain 2.4 g of Compound (2002) as a white powder.
¹ H-NMR and mass spectrum of the obtained compound (2002) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ1.37 (s, 18H), 2.14 (s, 3H)
MS (EI) m / z; 426 (M +)

Synthesis example 3
To a solution obtained by adding 6.98 g of sodium sulfide nonahydrate to 85 ml of N-methylpyrrolidone, 1.5 g of compound (2002) was added, and the mixture was stirred at 185 to 195 ° C. for 36 hours. After completion of the reaction, the reaction solution was poured into 300 ml of saturated aqueous ammonium chloride solution and extracted with toluene (200 ml × 3). The organic phase was washed with a saturated aqueous sodium chloride solution (300 ml × 3), the organic phase was dried over magnesium sulfate, the magnesium sulfate was removed, and then the solvent was distilled off. The obtained product was purified by silica gel column chromatography (hexane) to obtain 593 mg of the compound (2005) as a white solid.
¹ H-NMR and mass spectrum of the obtained compound (2005) were as follows.
¹ H-NMR (270MHz, CDCl ₃ , TMS): δ7.64 (d, J = 5.4Hz, 3H), 7.54 (d, J = 5.4Hz, 3H)
MS (EI) m / z; 246 (M +)

Synthesis example 4
Under a nitrogen atmosphere, 1.03 ml of N, N-diethylformamide (DMF) was added to a solution of 1.0 g of compound (2005) in 20 ml of 1,2-dichloroethane. Under ice-cooling, 1.24 ml of phosphorus oxychloride was slowly added. The reaction solution was heated under reflux for 24 hours while stirring, and further 30 ml of 1N sodium chloride aqueous solution was added, stirred at room temperature for 30 minutes, and extracted with chloroform. The chloroform phase was washed with saturated brine, dried over magnesium sulfate, magnesium sulfate was removed, and then chloroform was distilled off. The obtained product was purified by column chromatography (silica gel, chloroform, Rf = 0.5) to obtain 525 mg of compound (2006) as a pale yellow powder.
¹ H-NMR and mass spectrum of the obtained compound (2006) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ7.51-7,56 (m, 4H), 8.12 (s, 1H), 10.07 (s, 1H)
MS (EI) m / z; 274 (M +)

Synthesis example 5
424 mg of the compound (2006) was dissolved in 20 ml of dichloromethane, and a 5 ml solution of acetic acid to which 550 mg of N-bromosuccinimide (NBS) was added was added dropwise while maintaining at 0 ° C. or higher. The reaction was stirred at room temperature for 24 hours. The precipitate was collected by filtration and washed with water and ethanol. The obtained crystals were recrystallized from chlorobenzene to obtain 340 mg of the compound (2007) as a white powder.
¹ H-NMR and mass spectrum of the obtained compound (2007) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ7.94 (s, 2H), 8.15 (s, 1H), 10.03 (s, 1H)
MS (EI) m / z; 430 (M +)

Synthesis Example 6
Under ice cooling, 40 ml of a DMF solution of NBS (12.5 g) was added dropwise to 20 ml of a DMF solution of 11.8 g of 3-hexylthiophene over 1 hour. After stirring at room temperature for 12 hours, 50 ml of a saturated aqueous sodium hydrogen carbonate solution was added to precipitate succinimide. The precipitate was removed by celite filtration and washed with hexane. The filtrate was extracted with hexane (30 ml × 3), the organic phase was washed with water (30 ml × 3), dried over magnesium sulfate and the solvent removed. The obtained product was purified by distillation under reduced pressure to obtain 13.0 g of 2-bromo-3-hexylthiophene as a colorless oil as a target product.
¹ H-NMR of the obtained 2-bromo-3-hexylthiophene was as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.88 (t, J = 6.8 Hz, 3 H), 1.26-1.36 (m, 6 H), 1.56 (quint, J = 6.4 Hz, 2 H), 2.56 ( t, J = 8.0Hz, 2H), 6.79 (d, J = 5.6Hz, 1H), 7.18 (d, J = 5.6Hz, 1H)

Synthesis example 7
25 ml of a DMF solution of NBS (8.0 g) was added dropwise to 2,2′-bithiophene (3.7 g) over 30 minutes under ice cooling. After stirring at room temperature for 12 hours, the precipitated yellow solid was added with 100 ml of water and 300 ml of ethanol and filtered. The obtained product was recrystallized from hexane to obtain 5.2 g of the objective 4,4′-dibromo-2,2′-bithiophene as pale yellow plate crystals.
¹ H-NMR of the obtained 4,4′-dibromo-2,2′-bithiophene was as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 6.85 (dd, J = 4.0 Hz, 2H), 6.96 (dd, J = 4.0 Hz, 2H)

Synthesis Example 8
In a 100 ml three-necked flask purged with nitrogen, magnesium (1.25 g) and 1 ml of diethyl ether are added, and 11.9 g of 2-bromo-3-hexylthiophene is added dropwise over 20 minutes. When the reaction starts, reflux continues. Then, 10 ml of diethyl ether was added. The resulting Grignard reagent (300 ml) was refluxed for 2 hours, and a mixed solution of 4,4′-dibromo-2,2′-bithiophene (5.6 g) and Ni (dppp) Cl ₂ in diethyl ether 40 ml / benzene 30 ml in a three-necked flask. Over 30 minutes. After refluxing for 12 hours, the reaction was stopped by adding 100 ml of a saturated aqueous ammonium chloride solution under ice cooling. The precipitated salt was removed by Celite filtration and washed with chloroform. The filtrate was extracted twice with 50 ml chloroform and the organic phase was washed twice with 100 ml water and twice with 100 ml saturated aqueous sodium chloride solution. The chloroform phase was dried over magnesium sulfate, and after removing the magnesium sulfate, the solvent was distilled off. The resulting mixture was separated and produced by column chromatography (silica gel, hexane, Rf = 0.3 component) to obtain 6.8 g of compound (2008) as a yellow oil.
¹ H-NMR and mass spectrum of the obtained compound (2008) were as follows.
¹ H-NMR (400MHz, CDCl ₃ , TMS): δ0.89 (t, J = 7.2Hz, 6H), 1.26-1.40 (m, 12H), 1.65 (quint, J = 8.0Hz, 4H), 2.78 ( t, J = 8.0Hz, 4H), 6.94 (d, J = 5.2Hz, 2H), 7.02 (d, J = 4.0Hz, 2H), 7.13 (d, J = 3.6Hz, 2H), 7.18 (d, (J = 5.2Hz, 2H)
MS (GC) m / z; 498

Synthesis Example 9
Under a nitrogen atmosphere, 2.1 g of compound (2008) was dissolved in 45 ml of THF, cooled to −78 ° C., and 2.7 ml of n-butyllithium was added dropwise. The reaction was warmed to −30 ° C. over 30 minutes and 1.4 ml of tributyltin chloride was added. The reaction solution was stirred at room temperature for 4 hours, then poured into water and the organic phase extracted with chloroform was dried over magnesium sulfate, magnesium sulfate was removed, and the solvent was distilled off. The obtained product was purified by HPLC (JAIGEL-1H, 2H, CHCl3, Rv = 240 ml) to obtain 1.7 g of Compound (2009) as a yellow oil.
¹ H-NMR and mass spectrum of the obtained compound (2009) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.89-0.93 (m, 15H), 1.09-1.13 (m, 6H), 1.31-1.38 (m, 18H), 1.54-1.66 (m, 10H) , 2.78 (t, J = 8.3Hz, 2H), 2.80 (t, J = 8.3Hz, 2H), 6.94 (d, J = 5.4Hz, 1H), 6.96 (s, 1H), 7.01 (d, J = 3.9Hz, 1H), 7.02 (d, J = 4.0Hz, 1H), 7.12 (d, J = 3.9Hz, 1H), 7.18 (d, J = 5.4Hz, 1H)
MS (MALDI-TOF) calcd for 787.88 (M +); found 788.11

Synthesis Example 10
Under a nitrogen atmosphere, 132 mg of compound (2007) and 504 mg of compound (2009) were added to 10 ml of toluene, and 110 mg of Pd (PPh ₃ ) ₄ was further added, followed by heating under reflux for 18 hours. After cooling, the reaction solution was filtered with celite and washed with toluene, and the filtrate was dried under reduced pressure with an evaporator. The obtained product was purified by a medium pressure silica gel column (hexane: dichloromethane = 1: 1) to obtain 194 mg of compound (2010) as an orange solid.
¹ H-NMR and mass spectrum of the obtained compound (2010) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ0.89-0.94 (m, 12H), 1.32-1.45 (m, 24H), 1.61-1.66 (m, 8H), 2.62 (t, J = 8.1Hz , 4H), 2.77 (t, J = 8.1Hz, 4H), 6.93-7.05 (m, 16H), 7.11 (s, 2H), 7.18 (d, J = 3.8Hz, 2H), 7.19 (d, J = 3.8Hz, 2H), 7.80 (s, 1H), 9.92 (s, 1H)
MS (MALDI-TOF) calcd for 1266.24 (M +); found 1266.89

Synthesis Example 11
Under a nitrogen atmosphere, 1.0 g of compound (2008) and 25 ml of 1,2-dichloroethane were placed in a 50 ml three-necked flask, and 0.56 ml of phosphorus oxychloride and 0.16 ml of DMF were added under ice cooling, followed by refluxing for 17 hours. After returning to room temperature, the mixture was washed successively with 1N aqueous sodium hydroxide solution (100 ml), water (100 ml × 3) and saturated aqueous sodium chloride solution, dried over magnesium sulfate, and after removing magnesium sulfate, the solvent was distilled off. The obtained product was separated and purified by column chromatography (silica gel, dichloromethane: hexane = 1: 1, Rf = 0.36 component) to obtain 840 mg of compound (2011) as a red solid.
¹ H-NMR of the obtained compound (2011) was as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.89 (m, 6H), 1.29-1.41 (m, 12H), 1.61 (quint, J = 6.8Hz, 2H), 1.70 (quint, J = 6.8 Hz, 2H), 2.78 (t, J = 7.6Hz, 2H), 2.83 (t, J = 8.0Hz, 2H), 6.95 (d, J = 5.2Hz, 1H), 7.04 (d, J = 3.2Hz, 1H), 7.17 (d, J = 4.0Hz, 1H), 7.18 (d, J = 3.2Hz, 1H), 7.20 (d, J = 5.6Hz, 1H), 7.22 (d, J = 4.0Hz, 1H) , 7.60 (s, 1H), 9.83 (s, 1H)

Synthesis Example 12
Under ice cooling, a solution prepared by dissolving 460 mg of NBS in 15 ml of DMF was added dropwise to 50 ml of a mixed solution of 1.38 g of compound (2011) in DMF-CS ₂ (1: 1 / v: v) over 20 minutes. After stirring at room temperature for 12 hours, 50 ml of a saturated aqueous sodium hydrogen carbonate solution was added to the solution to precipitate succinimide. The precipitate was removed by Celite filtration and washed with chloroform. The filtrate was extracted with chloroform (100 ml × 3), this organic phase was washed with water (100 ml × 3), dried over magnesium sulfate, magnesium sulfate was removed, the solvent was distilled off, and compound (2012) 1. 47 g was obtained as a red-orange solid.
¹ H-NMR and mass spectrum of the obtained compound (2012) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.89 (m, 6H), 1.29-1.41 (m, 12H), 1.61-1.70 (m, 4H), 2.70 (t, J = 7.6Hz, 2H ), 2.81 (t, J = 8.0Hz, 2H), 6.91 (s, 1H), 6.99 (d, J = 3.2Hz, 1H), 7.17 (d, J = 4.0Hz, 1H), 7.18 (d, J = 3.2Hz, 1H), 7.22 (d, J = 4.0Hz, 1H), 7.60 (s, 1H), 9.83 (s, 1H)
MS (GC) m / z; 606

Synthesis Example 13
The same treatment as in Synthesis Example 9 was performed except that the compound (2005) was used instead of the compound (2008) to obtain 471 mg of the compound (2013) in a yield of 72% from 300 mg of the compound (2005).
¹ H-NMR and mass spectrum of the obtained compound (2013) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.92 (t, J = 7.3 Hz, 9H), 1.21 (t, J = 8.6 Hz, 6H), 1.30-1.42 (m, 6H), 1.61 ( quint, J = 4.6Hz, 6H), 7.48 (d, J = 5.1Hz, 2H), 7.59 (d, J = 4.9Hz, 1H), 7.64 (d, J = 5.1Hz, 2H)
MS (EI) m / z; 533 (M +)

Synthesis Example 14
511 mg of the compound (2012) and 452 mg of the compound (2013) were refluxed in the presence of 48 mg of Pd (PPH ₃ ) _{4 in} 20 ml of toluene for 16 hours. After completion of the reaction, the reaction solution was cooled to room temperature, filtered through celite, and washed with toluene. The filtrate was distilled off and dried to obtain the product. This product was purified by medium pressure silica gel chromatography (dichloromethane) and recrystallized with a mixed solvent of hexane-chloroform to obtain 560 mg of compound (2014) as a red powder.
The MS spectrum and elemental analysis results of the obtained compound (2014) were as follows.
MS (DI) m / z; 770 (M +)
Anal.Calcd (%) for C ₄₁ H ₃₈ OS ₇ : C63.85, H4.97; Found C63.61, H4.94

Synthesis Example 15
Under a nitrogen atmosphere, 700 mg of the compound (2012) and 960 mg of the compound (2009) were dissolved in 55 ml of anhydrous toluene, and degassed by blowing argon gas for 15 minutes. 50 mg of Pd (PPh ₃ ) ₄ was added and refluxed for 20 hours. After completion of the reaction, the reaction solution was filtered through Celite, and the solvent was distilled off. The obtained product was purified by silica gel column chromatography (methylene chloride: hexane = 1: 1 / v: v, Rf = 0.44 component) to obtain 1.1 g of compound (2015) as a red solid.
¹ H-NMR of the obtained compound (2015) was as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.87-0.92 (m, 12H), 1.31-1.41 (m, 24H), 1.66-1.70 (m, 8H), 2.75-2.78 (m, 8H) 6.95 (d, J = 5.3Hz, 2H), 7.01 (s, 2H), 7.03 (d, J = 3.8Hz, 2H), 7.04 (d, J = 3.6Hz, 2H), 7.06 (d, J = 3.6Hz, 2H), 7.14 (d, J = 3.9Hz, 2H), 7.17-7.22 (m, 6H), 7.60 (s, 1H), 9.83 (s, 1H)

Synthesis Example 16
332 mg of compound (2015) was added to a mixed solution of 30 ml of DMF and 10 ml of CS ₂ , cooled to 0 ° C., 67 mg of NBS was gradually added, and the mixture was stirred at room temperature for 15 hours. A saturated aqueous sodium hydrogen carbonate solution was added to the reaction solution to precipitate succinimide. The solid was removed by celite filtration, and the organic phase obtained by extracting the filtrate with dichloromethane was washed with water, dried over magnesium sulfate, magnesium sulfate was removed, and then the solvent was distilled off. The obtained product was recrystallized from a dichloromethane-hexane mixed solvent to obtain 322 mg of the compound (2016) as a red solid.
¹ H-NMR and mass spectrum of the obtained compound (2016) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ , TMS): δ 0.87-0.92 (m, 12H), 1.29-1.41 (m, 24H), 1.60-1.70 (m, 8H), 2.75-2.78 (m, 8H) , 6.91 (s, 1H), 6.97 (s, 1H), 7.01 (s, 2H), 7.03 (d, J = 3.8Hz, 1H), 7.06 (d, J = 3.6Hz, 1H), 7.08 (d, J = 3.6Hz, 1H), 7.14 (d, J = 3.9Hz, 2H), 7.17-7.22 (m, 2H), 7.60 (s, 1H), 9.86 (s, 1H)
MS (MALDI-TOF) calcd for 1102.56 (M +); found 1103.00

Synthesis Example 17
The same treatment as in Synthesis Example 14 was performed, except that compound (2016) was used instead of compound (2012), and 160 mg of compound (2017) was obtained from 146 mg of compound (2016) with a yield of 96%.
The MS spectrum of the obtained compound (2017) was as follows.
MS (MALDI-TOF) calcd foe 1268.02 (M +); found 1267.87

Synthesis Example 18
Compound (2005) (500 mg) was dissolved in dichloromethane (40 ml), and a solution of NBS (1.08 g) in acetic acid (10 ml) was added at 0 ° C., and the mixture was stirred at room temperature for 24 hours. The precipitated crystals were collected by filtration and washed with water and ethanol to recrystallize the resulting solid with chlorobenzene to obtain 1.27 g of compound (2018) as a white powder.
¹ H-NMR and mass spectrum of the obtained compound (2018) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ7.61 (s, 3H)
MS (EI) m / z; 426 (M +)

Synthesis Example 19
Under a nitrogen atmosphere, 2.12 g of compound (2018) and 412 mg of compound (2009) were added to 40 ml of toluene, and 147 mg of Pd (PPh ₃ ) ₄ was further added, followed by heating under reflux for 16 hours. After the reaction, the reaction solution was cooled, the reaction solution was filtered on celite, washed with toluene, and then the solvent was distilled off. The product was purified by medium pressure silica gel column chromatography (hexane: dichloromethane = 1: 1) to obtain 545 mg of compound (2019) as an orange solid.
¹ H-NMR and mass spectrum and elemental analysis of the obtained compound (2019) were as follows.
¹ H-NMR (270 MHz, CDCl ₃ , TMS): δ 0.88-0.96 (m, 18H), 1.25-1.55 (m, 36H), 1.61-1.72 (m, 12H), 2.67 (t, J = 8.1Hz , 6H), 2.78 (t, J = 8.1Hz, 6H), 6.94 (d, J = 5.4Hz, 3H), 6.97 (s, 3H), 6.98 (d, J = 3.8Hz, 3H), 7.02 (s , 3H), 7.06 (d, J = 3.8Hz, 3H), 7.07 (d, J = 3.8Hz, 3H), 7.17 (d, J = 5.4Hz, 3H)
MS (MALDI-TOF) calcd for 1734.38 (M +); found 1734.68
Anal.calcd (%) C = 66.39, H = 5.92, Found C = 65.77, H = 5.81

Synthesis Example 20
Using the formylation method used in the synthesis of compound (2011) described above, 688 mg of compound (2019) was formylated to give 465 mg (yield 66%) of compound (2020) as a red solid.
The mass spectrum of the obtained compound (2020) was as follows.
MS (MALDI-TOF) calcd for 1762.37 (M +); found 1762.17

Example 1
Under a nitrogen atmosphere, 0.78 ml of piperidine, 262 mg of the compound (2010) and 35 mg of cyanoacetic acid were stirred and reacted in a mixed solution of 4.7 ml of dry chloroform and 4.7 ml of acetonitrile for 15 hours. After completion of the reaction, 47 ml of 10% aqueous acetic acid solution was added, and the resulting organic phase was extracted with chloroform-water. The organic phase obtained was washed with saturated brine, dried over magnesium sulfate, magnesium sulfate was removed, and the solvent was removed. Was distilled off. The obtained solid was purified by silica gel chromatography (chloroform) to obtain 113 mg of compound (9) as a dark red solid.
The mass spectrum of the obtained compound (9) was as follows.
MS (MALDI-TOF) calcd for 1335.07 (M +); found 1335.24

Example 2
The same treatment as in Example 1 was carried out except that the compound (2014) was used instead of the compound (2010) to obtain 280 mg of the compound (7) as a dark red solid from 300 mg of the compound (2014).
The MS spectrum and elemental analysis results of the obtained compound (7) were as follows.
MS (MALDI-TOF) calcd for 838.25 (M +); Found 838.07
Anal.Calcd (%) for C ₄₄ H ₃₈ NO ₂ S ₇ : C63.04, H4.69, N1.67; found C63.04, H4.69, N1.67

Example 3
The same treatment as in Example 1 was performed, except that the compound (2017) was used instead of the compound (2010), and 150 mg of the compound (8) was obtained as a dark red solid from 167 mg of the compound (2017).
The MS spectrum and elemental analysis results of the resulting compound (8) were as follows.
MS (MALDI-TOF) calcd for 1335.07 (M +); Found 1335.06
Anal.Calcd (%) for C ₄₄ H ₃₈ NO ₂ S ₇ : C63.04, H4.69, N1.67; found C63.04, H4.69, N1.67

Example 4
The same treatment as in Example 1 was carried out except that the compound (2020) was used instead of the compound (2010) to obtain 120 mg of the compound (10) as a dark red solid from 330 mg of the compound (2020).
The mass spectrum of the obtained compound (10) was as follows.
MS (MALDI-TOF) calcd for 1829.38 (M +); found 1830.10

  Various physical property data of the dyes (7) to (10) are shown in Table 2. The oxidation potential (E1 / 2ox / V) was measured using Hokuto Denko HA-301 potentiostat and Hokuto Denko HB-104 function generator.

Examples 5-10
Using the dyes (7) to (10) obtained in Examples 1 to 4, dye-sensitized solar cell elements were produced by the following production method.
FTO glass (1.5 cm × 2.5 cm) was ultrasonically cleaned with distilled water, acetone, and 2-propanol for 10 minutes each. Thereafter, UV-O ₃ irradiation was performed for 20 minutes. Titanium dioxide paste (PST-18NR manufactured by Catalyst Kasei Kogyo Co., Ltd .: average particle size 20 nm) was applied to the conductive surface with a doctor blade (height 50 μm) and sintered at 500 ° C. for 50 minutes to obtain a titanium oxide thin film electrode. . The titanium oxide thin film electrode was immersed in a chloroform solution of a dye compound having a concentration of 0.3 mM for 12 hours to adsorb the dye to obtain a dye-adsorbed titanium oxide thin film electrode. And the dye-adsorbed titanium oxide film electrode and a Pt counter electrode obtained by depositing Pt on the FTO, as shown in FIG. 1, a redox electrolyte solution _{(0.05M LiI, 0.05M I 2,} 0.6M 1- propyl - 2,3-dimethylimidazolium iodide, acetonitrile solution of 0.5M t-butylpyridine) was placed, and the periphery of the redox electrolyte solution was packed using parafilm to obtain a device.

The power generation area of the battery to be measured is 0.25 cm ² , the light source is Newport Model 67005 50-500 W, it is 100 mW / cm ² through an AM (atmosphere passing air amount) 1.5 filter, and the measurement is performed using a KEITKEYKEY 2400 Source Meter. Went.

  Table 3 shows the battery performance evaluation results of the dye-sensitized solar cells using the compounds (7) to (10).

  From the results in Table 3, in the compounds of the present compounds (7) to (10), excellent photoelectric conversion efficiency was obtained in all cases. In particular, when compound (9) was used, it was found that Voc (open circuit voltage) was as extremely high as 0.835 V, which was suitable for high voltage applications.

  By using the dye of the present invention having a specific structure or a salt thereof as a sensitizing dye, a photoelectric conversion element and a solar cell with high conversion efficiency and high stability can be obtained.

Claims (19)

A photoelectric conversion element obtained by supporting a dye represented by the following formula (1) or a salt thereof on a thin film of oxide semiconductor fine particles provided on a substrate.

(In formula (1), X _{1 to} X ₃ each represents an oxygen atom, a sulfur atom or a selenium atom. R _{1 to} R ₆ each independently represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom. An atom, an amino group, an alkoxyl group or the following formula (2) is represented, and at least one of R _{1 to} R ₆ is the following formula (2).

(In Formula (2), Y ₁ and Z ₁ each independently represent a hydrogen atom, a carboxyl group, a cyano group, or a phosphoric acid group. Q ₁ represents an oxygen atom, a sulfur atom, or a selenium atom. A _{1 to} A ₃ Each independently represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, m1 represents an integer of 0 to 16. In formula (2), * represents a formula ( 1) represents the bonding position of R _{1 to} R ₆ . The R ₁ is represented by the formula (2), and R _{2 to} R ₆ are each independently a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a halogen atom, an amino group, or an alkoxyl group. Photoelectric conversion element. The photoelectric conversion element according to claim 2, wherein Q ₁ is a sulfur atom. The photoelectric conversion element according to claim 3, wherein R ₁ is represented by the following formula (3).

(In the formula (3), A ₁ , Y ₁ and Z ₁ represent the same meaning as in the formula (2) according to claim 1. A _{4 to} A ₁₁ are a hydrogen atom, an aliphatic hydrocarbon group, Represents an aromatic hydrocarbon group, a halogen atom or an alkoxyl group, n1 represents an integer of 0 to 4. * represents the bonding position of R _{1 in} formula (1). The photoelectric conversion element according to claim 4, wherein A ₅ and A ₁₀ are aliphatic hydrocarbon groups. The photoelectric conversion element according to claim _5, wherein A ₅ and A ₁₀ are n-hexyl groups. The photoelectric conversion element according to any one of claims 4 to 6, wherein A ₄ , A _{6 to} A ₉ and A ₁₁ are all hydrogen atoms.   The photoelectric conversion element according to any one of claims 4 to 7, wherein n1 is an integer of 0 to 2. The photoelectric conversion according to any one of claims 2 to 8, wherein R ₂ , R ₄ and R ₆ are all hydrogen atoms, and R ₃ and R ₅ are each independently a hydrogen atom or an aromatic hydrocarbon group. element. The photoelectric conversion element according to claim 9, wherein R ₃ and R ₅ are both represented by the following formula (4).
The photoelectric conversion device as claimed in any one of claims 1 to 10 X ₁ to X ₃ are each a sulfur atom. The photoelectric conversion element according to claim ₁ , wherein at least _one of Y ₁ and Z ₁ is a carboxyl group. The photoelectric conversion element according to claim 12, wherein any _one of Y ₁ and Z ₁ is a carboxyl group, and the other is a cyano group. The photoelectric conversion device according to claim 13, wherein Y ₁ is a carboxyl group and Z ₁ is a cyano group. The photoelectric conversion device as claimed in any one of claims 1 to 14 A ₁ is a hydrogen atom. The photoelectric conversion element according to claim 1, wherein the dye represented by the formula (1) or a salt thereof is any one of the following formulas (7) to (10).
  The solar cell which uses the photoelectric conversion element as described in any one of Claims 1 thru | or 16.   The pigment | dye represented by Formula (1) of Claim 1, or its salt.   The pigment | dye represented by Formula (7) thru | or (10) of Claim 16, or its salt.