JP2001006761A - Photoelectric conversion material, photoelectric conversion element and polymethine pigment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric conversion material having high photoelectric conversion element characteristics in near infrared to infrared areas, a photoelectric conversion element using it and polymethine pigment. SOLUTION: These are a photoelectric conversion material containing semiconductor fine grains sensitized by pigment represented by a formula, a photoelectric conversion element using the material and polymethine pigment. In the formula, R1 is any one of O, S, Se, Te, =NR9, =CR10 R11. R9 is hydrogen, alkyl group and aryl group. R10, R11 are each a substitutional group. A ring may be formed by connecting R10, R11 each other. R2 is O-, S-, Se-, Te-, -NR12-. R12 is hydrogen, alkyl group and aryl group. R3 to R8 are each hydrogen or substitutional group and (m) is 0 or 1. P1, P2 are each cycloalkenecyclic group or heterocyclic group. W1 represents counter ion when counter ion is required to neutralize electric charge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photoelectric conversion material using semiconductor fine particles sensitized with a dye, and a photoelectric conversion element using the same. Further, the present invention relates to a polymethine dye used for a photoelectric conversion material, a photoelectric conversion element, and the like.

[0002]

2. Description of the Related Art Photovoltaic power generation is a single-crystal silicon solar cell,
Polycrystalline silicon solar cells, amorphous silicon solar cells, and compound solar cells such as cadmium telluride and indium copper selenide have been put into practical use or subject to major research and development.
It is necessary to overcome problems such as a long energy payback time. On the other hand, many solar cells using an organic material intended to have a large area and a low price have been proposed so far, but have a problem that conversion efficiency is low and durability is poor. Under these circumstances, Nature (Vol.353, 737-
(Pp. 740, 1991) and U.S. Pat. No. 4,492,721 disclose a photoelectric conversion element and a solar cell using semiconductor fine particles sensitized by a dye, as well as materials and manufacturing techniques for producing the same. The proposed battery is a wet solar cell using a titanium dioxide porous thin film spectrally sensitized by a ruthenium complex as a working electrode. The first advantage of this method is that an inexpensive oxide semiconductor such as titanium dioxide can be used without purification to a high degree of purity, so that an inexpensive photoelectric conversion element can be provided. Since the absorption of the dye is broad, light in almost all wavelength ranges of visible light can be converted into electricity.

One of the demands for improvement of dye-sensitized photoelectric conversion elements is to use expensive ruthenium complex dyes as sensitizing dyes, and development of photoelectric conversion elements sensitized by inexpensive organic dyes has been required. Was wanted. Such an example is disclosed in Japanese Patent Application Laid-Open No. 11-86916 and European Patent EP09 / 09.
Although a method using the compound described in 11841A is known, it has not been possible to obtain a high photoelectric conversion efficiency in a near infrared to infrared light region.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dye having an inexpensive and high conversion efficiency by using an organic dye having absorption in the near infrared to infrared region and capable of efficiently sensitizing semiconductor fine particles. An object is to provide a sensitized photoelectric conversion element.

[0005]

The above objects have been attained by the following items which specify the present invention and preferable items. (1) A photoelectric conversion material comprising semiconductor fine particles sensitized by a dye represented by the general formula (I).

[0006]

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In the general formula (I), R₁Are oxygen, sulfur, selenium
N, tellurium, = NR₉, = CR_TenR₁₁ Table
Then R₉Represents a hydrogen, an alkyl group, an aryl group,
R_Ten, R₁₁Each independently represents a substituent. R_Ten, R₁₁
May be connected to each other to form a ring. R_TwoIs O^-,
S^-, Se^-, Te^-, -NR₁₂ ^-And R₁₂Is hydrogen,
Represents an alkyl group or an aryl group. R_Three~ R₈Are independent
Represents hydrogen or a substituent, and m represents 0 or 1. P
₁, P_TwoAre each independently cycloalkene ring groups or
Represents a ring group. W₁Has a counter ion to neutralize the charge
Represents the counter ion if necessary. (2) In the general formula (I), P₁, P_TwoIs cycloprope
Ring, cycloheptadiene ring, cyclohexadiene ring,
Benzocyclohexadiene ring, benzothiazole ring,
Benzoxazole ring, benzoselenazole ring, benzothe
Lurazole ring, 2-quinoline ring, 4-quinoline ring, ben
Zoimidazole ring, thiazoline ring, indolenine ring, e
Xadiazole ring, thiazole ring, imidazole ring
Which may be substituted or condensed
(1) The photoelectric conversion material according to (1), (3) R in general formula (I)_Three~ R₈But each independently water
, An alkyl group, an alkenyl group, a cycloalkyl group,
(1) a reel group or a heterocyclic group;
Or the photoelectric conversion material of (2). (4) The dye represented by the general formula (I) is represented by the general formula (II)
(1) to (3)
Fees.

[0008]

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In the general formula (II), R₁, R_Two, W₁Is the general formula
It is synonymous with (I). R₁₃, R₁₄Are each independently water
A hydrogen atom, an alkyl group, an alkenyl group, or an aryl group;
_{twenty three}~ R₂₈ Are independently hydrogen, alkyl, alkenyl
Group, cycloalkyl group, aryl group, and heterocyclic group.
You. Y₁, Y_TwoAre independently oxygen, sulfur, selenium,
Lulu, -CR₁₇R₁₈-, -NR₁₉-Represents R₁₇,
R₁₈, R₁₉Are each independently hydrogen, an alkyl group,
Represents a nyl group or an aryl group. R_Fifteen, R₁₆Are independent
Represents a substituent, and a and b are each independently an integer of 0 to 4
Represents When a is 2 or more, R_FifteenAre the same or different
They may be connected to each other to form a ring. b is 2 or more
When, R₁₆May be the same or different
A ring may be formed. (5) R in general formula (I) or (II)_Ten, R₁₁But it
Each independently cyano, alkoxycarbonyl, carbo
Xyl group, acyl group, acyloxy group, thioacylthio
Group, alkylsulfonyl group, arylsulfonyl group,
Sulfonic acid group, sulfonamide group, carbamoyl group,
Groups, acylamino groups, alkyl groups, alkenyl groups,
Reel group, alkoxy group, alkylthio group, arylo group
Xy, heterocyclic, phosphonyl, phosphoryl,
(1)-characterized by being represented by a droxamate group
(4) The photoelectric conversion material. (6) R in general formula (II)_Fifteen, R₁₆Are independent of each other.
Ano group, alkoxycarbonyl group, carboxyl group,
Sil group, acyloxy group, alkylsulfonyl group, ant
Sulfonic acid group, sulfonic acid group, sulfonamide group,
Carbamoyl group, amino group, acylamino group, alkyl
Group, alkenyl group, aryl group, alkoxy group, alk
Luthio group, aryloxy group, heterocyclic group, phosphonyl
Group, phosphoryl group, hydroxamic acid group, hydroxyl
Group, alkynyl group, cycloalkyl group, halogen atom
(4) or (5), characterized in that:
Fees. (7) The dye represented by the general formula (II) is represented by the following general formula (II)
(4) to (6) characterized by being represented by I)
Conversion material.

[0010]

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In the general formula (III), R_Two, R₁₃, R₁₄, R_{twenty three}
~ R₂₈, Y₁, Y_Two, A, b, m, W₁Is the general formula (II)
It is synonymous. R_{twenty one}Is oxygen, sulfur, selenium, tellurium, = N
R₉, = CR₃₁R₃₂R represents any of₉Is hydrogen, al
A kill group or an aryl group is represented by R₃₁ , R₃₂Are independent of each other.
Ano group, alkoxycarbonyl group, carboxyl group,
Sil group, acyloxy group, thioacylthio group, alkyl
Sulfonyl group, arylsulfonyl group, sulfonic acid group,
Sulfonamide group, carbamoyl group, amino group, acyl
Amino group, alkyl group, alkenyl group, aryl group,
Alkoxy group, alkylthio group, aryloxy group, hete
Rocyclic group, phosphonyl group, phosphoryl group, hydroxamic acid
Represents a group. R₃₁, R₃₂Are linked together to form a ring
Good. R₂₉, R₃₀Are each independently a cyano group or an alkoxy group
Cicarbonyl group, carboxyl group, acyl group, acyl group
Xy group, alkylsulfonyl group, arylsulfonyl
Group, sulfonic acid group, sulfonamide group, carbamoyl
Group, amino group, acylamino group, alkyl group, alkenyl
Group, aryl group, alkoxy group, alkylthio group,
Reeloxy group, heterocyclic group, phosphonyl group, phosphoryl
Group, hydroxamic acid group, hydroxyl group, alkynyl
A cycloalkyl group, a halogen atom. (8) In general formulas (I) to (III), R_TwoIs O^-Being
(1) to (7). (9) R in general formulas (I) and (II)₁Is oxygen or =
CR_TenR₁₁In formula (III), R_{twenty one}Is oxygen
Or = CR₃₁R₃₂It is characterized by being represented by
(1) to (8). (10) R in general formulas (I) and (II)₁, The general formula (II
R in I)_{twenty one}Are each oxygen.
(1) to (9). (11) R in the general formulas (I) and (II)₁Is = CR_TenR
₁₁In formula (III), R_{twenty one}Is = CR₃₁R₃₂To
(1) to (10).
Photoelectric conversion material. (12) R in general formulas (I) and (II)_Ten, R₁₁,one
R in general formula (III)₃₁ , R₃₂But each independently
Group, alkoxycarbonyl group, carboxyl group, reed
Group, alkylsulfonyl group, arylsulfonyl group,
Sulfonic acid group, carbamoyl group, heterocyclic group, phosphoni
(1) to (11), characterized in that the light is represented by
Electric conversion material. (13) R in the general formulas (I) and (II)_Ten, R₁₁,one
R in general formula (III)₃₁ , R₃₂Are connected to each other
(1) to (12), wherein
Photoelectric conversion material. (14) R in the general formulas (I) and (II)_TenAnd R₁₁Also
Is R in the general formula (III)₃₁And R₃₂Are connected to form
Wherein the ring is a 5- or 6-membered ring (1)-
The photoelectric conversion material according to (13). (15) R in the general formula (I)_Three~ R₈, The general formula (I
R in I) and (III)_{twenty three}~ R₂₈Are both hydrogen
The photoelectric conversion material according to any one of (1) to (14), wherein (16) R in the general formula (II) or (III)₁₃, R
₁₄(4) to (1) are alkyl groups.
5) The photoelectric conversion material. (17) In general formulas (II) and (III), Y₁, Y_TwoBut
-CR₁₇R₁₈(4)-characterized by being represented by-
(16) The photoelectric conversion material. (18) The dyes represented by the general formulas (I) to (III)
Characterized by having at least one acidic group (1)
To (17). (19) The acidic group is a carboxyl group, a phosphonyl group, a phos
Holyl group, sulfonic acid group, hydroxyl group, hydroxa
(18) The light according to (18), which is any one of a humic acid group
Electric conversion material. (20) The semiconductor fine particles sensitized by the dye are
(1)-(19)
Photoelectric conversion material. (21) The photoelectric conversion material according to any one of (1) to (20)
Having a coated conductive support, charge transfer layer and counter electrode
Photoelectric conversion element. (22) It is represented by the following general formula (III)
Polymethine dye.

[0012]

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In the general formula (III), R_Two, R₁₃, R₁₄, R_{twenty three}
~ R₂₈, Y₁, Y_Two, A, b, m, W₁Is the general formula (II)
It is synonymous. R_{twenty one}Is oxygen, sulfur, selenium, tellurium, = N
R₉, = CR₃₁R₃₂R represents any of₉Is hydrogen, al
A kill group or an aryl group is represented by R₃₁ , R₃₂Are independent of each other.
Ano group, alkoxycarbonyl group, carboxyl group,
Sil group, acyloxy group, thioacylthio group, alkyl
Sulfonyl group, arylsulfonyl group, sulfonic acid group,
Sulfonamide group, carbamoyl group, amino group, acyl
Amino group, alkyl group, alkenyl group, aryl group,
Alkoxy group, alkylthio group, aryloxy group, hete
Rocyclic group, phosphonyl group, phosphoryl group, hydroxamic acid
Represents a group. R₃₁, R₃₂Are linked together to form a ring
Good. R₂₉, R₃₀Are each independently a cyano group or an alkoxy group
Cicarbonyl group, carboxyl group, acyl group, acyl group
Xy group, alkylsulfonyl group, arylsulfonyl
Group, sulfonic acid group, sulfonamide group, carbamoyl
Group, amino group, acylamino group, alkyl group, alkenyl
Group, aryl group, alkoxy group, alkylthio group,
Reeloxy group, heterocyclic group, phosphonyl group, phosphoryl
Group, hydroxamic acid group, hydroxyl group, alkynyl
A cycloalkyl group, a halogen atom. a is 2 or more
When above, R₂₉May be the same or different and are connected to each other
To form a ring. When b is 2 or more, R₃₀Is the same
And may be linked to each other to form a ring
No.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The dye of the present invention represented by formula (I) will be described in detail below. When the compound of the present invention contains an alkyl group, an alkenyl group, an alkynyl group, an alkylene group, etc., they may be linear or branched, and may be substituted or unsubstituted. When the compound of the present invention contains an aryl group, a heterocyclic group, a cycloalkyl group and the like, they may be substituted or unsubstituted, and may be monocyclic or condensed. The hetero atom of the heterocyclic group of the present invention represents, for example, oxygen, nitrogen, sulfur, selenium, tellurium and the like.

In the general formula (I), R₁Are oxygen, sulfur, selenium
N, tellurium, = NR₉, = CR_TenR₁₁ Table
And oxygen, sulfur, = NR₉, = CR_TenR₁₁That it is
Preferably, oxygen, = CR_TenR₁₁More preferred to be
No.

R ₉ is hydrogen, an alkyl group (preferably having 1 to 20 carbon atoms (hereinafter referred to as C number), for example, methyl, ethyl, n-propyl, i-propyl, t-butyl, n-
Butyl, 2-ethylhexyl, benzyl, 2-ethoxyethyl, 1-carboxylmethyl, 2-carboxylethyl, 3-carboxylpropyl, 3-sulfopropyl, 4-sulfobutyl, 2-phosphorylethyl, 2-phosphonylethyl), aryl Group (preferably 6 to 2 carbon atoms)
0, for example, phenyl, 2-naphthyl, 4-carboxylphenyl, 3-sulfophenyl, 4-methoxyphenyl), and hydrogen or an alkyl group is preferable.

R ₁₀ and R ₁₁ each independently represent a substituent, preferably a cyano group or an alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, for example, ethoxycarbonyl,
-Ethylhexyloxycarbonyl, cyclohexyloxycarbonyl), carboxyl group, acyl group (preferably having 1 to 20, for example, acetyl, benzoyl), acyloxy group (preferably having 1 to 20, for example, acetyloxy, benzoyloxy), thioacylthio Groups (preferably having 1 to 20, for example, thioacetylthio, thiobenzoylthio), alkylsulfonyl groups (preferably having 1 to 20, for example, methanesulfonyl, i-butanesulfonyl), and arylsulfonyl groups (preferably having a C number of 1 to 20) 6
To 26, for example, benzenesulfonyl, 4-methoxybenzenesulfonyl), a sulfonic acid group (—SO ₃ H), and a sulfonamide group (preferably having a C number of 0 to 20, for example, N, N
-Dimethylsulfonamide, N-phenylsulfonamide), a carbamoyl group (preferably having 1 to 20, for example, N, N-dimethylcarbamoyl, N-phenylcarbamoyl), an amino group (preferably having 0 to 20, for example, amino) , N, N-dimethylamino, anilino), an acylamino group (preferably having 1 to 20 carbon atoms such as acetylamino, benzoylamino), an alkyl group (preferably C
Formulas 1 to 20, for example, methyl, ethyl, i-propyl, t
-Butyl), alkenyl group (preferably having 2 to 20 carbon atoms,
For example, vinyl, allyl, oleyl), an aryl group (preferably having 6 to 26 carbon atoms, for example, phenyl, 1-naphthyl,
4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl, 4-carboxylphenyl, 3-sulfophenyl), alkoxy group (preferably having 1 to 20 carbon atoms such as methoxy, i-propoxy), alkylthio group (preferably C 1 to 20, for example, methylthio), an aryloxy group (preferably 6 to 26, for example, phenoxy, 2-naphthyloxy), a heterocyclic group (preferably C
A number 2 to 20, e.g., 2-thiazolyl, 2-oxazolyl), a phosphonyl group (e.g., a C number of 0 to 20, e.g., -P
_{O (OH) 2, -PO (} OC 2 H 5) 2), a phosphoryl group (preferably having a C number of 0 to 20, for example, -OPO (O
_{H) 2, -OPO (OC 2} H 5) 2), a hydroxamic acid group (preferably having a C number of 1 to 20, for example -CONHOH, -
CON (CH ₃ ) OH), more preferably a cyano group, an alkoxycarbonyl group, a carboxyl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonic acid group, a carbamoyl group, a heterocyclic group, a phosphonyl group, More preferably, it represents a cyano group, an alkoxycarbonyl group, a carboxyl group, an alkylsulfonyl group, or a heterocyclic group. Note that R ₁₀ and R ₁₁ may be the same or different.

R ₁₀ and R ₁₁ may be linked to each other to form a ring. At that time, it is preferable to form a 5- or 6-membered ring, a cycloalkane ring, a cycloalkene ring and a hetero ring are preferably formed, more preferably a hetero ring is formed, and a pyrazolidinedione ring and barbi Tool acid ring, thiobarbituric acid ring, isoxazolone ring, pyrazolone ring, pyridone ring, rhodanine ring, pyrrolotriazole ring, pyrazolotriazole ring, indandione ring,
It is more preferable to form a hydantoin ring, a thiohydantoin ring, a thiazolidinedione ring, an oxazolidinonethione ring, and a pyrazolidinedione ring, a pyrazolone ring, a rhodanin ring, an indandione ring, a thiazolidinedione ring,
It is more preferable to form an oxazolidinonethione ring, and it is particularly preferable to form a pyrazolidinedione ring, a pyrazolone ring and a rhodanine ring. In the present invention, the cycloalkane ring group is represented by a cyclic hydrocarbon ring, has no unsaturated bond in the ring portion, and has a hydrocarbon bonding structure in which ＯO or the like can be bonded to a ring carbon atom. The ring may be condensed with an aromatic ring (such as a benzene ring) or may have a substituent. The cycloalkane ring preferably has 3 to 40 carbon atoms, preferably a 5- or 6-membered ring, and more preferably a 4,4-dimethylcyclohexane-2,6-dione ring, an indandione ring or the like. In the present invention, the cycloalkene ring group is represented by a cyclic hydrocarbon ring, has at least one double bond in the ring portion, and has a hydrocarbon ring structure to which a ＯO or the like can be bonded to a ring carbon atom. Further, the ring refers to a ring represented by a ring group in which an aromatic ring (such as a benzene ring) may be condensed or may have a substituent. The cycloalkene ring preferably has 3 to 40 carbon atoms, and is preferably a 5- or 6-membered ring, and is preferably an oxocyclohexadiene ring, an oxobenzocyclohexadiene ring, or the like.

[0019] Hereinafter, = CR ₁₀ shown by R ₁₁ Preferred examples of the ring R ₁₀ and R ₁₁ are formed by connecting in detail, but the present invention is not limited thereto.

[0020]

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[0021]

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[0022] In the general formula (I), R ₂ is ^{O -, S -, Se -} ,
Te ^-, -NR12 ^- represents preferably ^{O -,} S -, -N
R ₁₂ ^-, more preferably an O ^- a. R ₁₂ is hydrogen,
Represents an alkyl group or an aryl group (preferable examples are the same as R ₉ ), and is preferably hydrogen or an alkyl group.

In the general formula (I), R _{3 to} R ₈ each independently represent hydrogen or a substituent (preferable examples are the same as R ₁₀ and R ₁₁ ), preferably hydrogen and an alkyl group (preferable examples are R
₉ ), an alkenyl group (preferably having 2 to 20 carbon atoms,
For example, allyl, vinyl, oleyl), cycloalkyl group (preferably having 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl), aryl group (preferable examples are the same as R9), heterocyclic group (Preferably has 1 to 20 carbon atoms, for example, 4-pyridyl, 2-pyridyl, 1-imidazolyl, 1-oxazolyl, 1-thiazolyl), preferably represents hydrogen, an alkyl group, or an alkenyl group, and more preferably represents hydrogen. Represent. In the general formula (I), m represents 0 or 1, and more preferably 0.

In the general formula (I), P ₁ and P ₂ each independently represent a cycloalkene ring group (preferably having 3 to 40 carbon atoms) or a heterocyclic group (preferably having 1 to 40 carbon atoms), and more preferably May be substituted or condensed. P ₁ ,
P ₂ is more preferably a heterocyclic group. P ₁ , P ₂
Are cyclopropene, cyclopentadiene, cyclohexadiene, benzocyclohexadiene, benzothiazole, benzoxazole, benzoselenazole, benzotellurazole, 2-quinoline, 4-quinoline, Represents a benzimidazole ring, a thiazoline ring, an indolenine ring, an oxadiazole ring, a thiazole ring, or an imidazole ring, and more preferably, any of which may be substituted or condensed, a benzothiazole ring, a benzoxazole ring, a benzoselenazole Represents a ring, a benzotellurazole ring, a 2-quinoline ring, a 4-quinoline ring, a benzimidazole ring, or an indolenine ring, and more preferably any of them may be substituted or condensed.
It represents a benzothiazole ring, a benzoxazole ring, a benzimidazole ring, or an indolenine ring, and particularly preferably represents an indolenine ring.

In the general formula (I), W ₁ represents a counter ion when a counter ion is required to neutralize the charge. Whether a dye is a cation, an anion, or has a net ionic charge depends on its auxochrome and substituents. When the substituent has a dissociable group, it may dissociate and have a negative charge, and in this case, the charge of the entire molecule is neutralized by W ₁ . Typical cations are inorganic or organic ammonium ions (eg, tetraalkylammonium ions, pyridinium ions), alkali metal ions, and protons, while the anions are specifically either inorganic or organic anions. For example, a halogen anion (eg, fluoride ion, chloride ion, bromide ion, iodide ion), a substituted arylsulfonic acid ion (eg, p-toluenesulfonic acid ion, p-chlorobenzenesulfonic acid) Ion), aryldisulfonate ion (for example,
1,3-benzenedisulfonate ion, 1,5-naphthalenedisulfonic acid ion, 2,6-naphthalenedisulfonic acid ion), alkyl sulfate ion (for example, methyl sulfate ion), sulfate ion, thiocyanate ion, perchlorate ion , Tetrafluoroborate ion, picrate ion, acetate ion and trifluoromethanesulfonic acid ion. Further, an ionic polymer or another dye having a charge opposite to that of the dye may be used as the charge-balancing counter ion, or a metal complex ion (for example, bisbenzene-1,2-dithiolatonic nickel (III)) may be used. is there

The dye represented by the general formula (I) is
It is preferred to be represented by I). In the general formula (II), R ₁ ,
R ₂ and W ₁ have the same meanings as in formula (I). R ₁₃ and R ₁₄ each independently represent hydrogen, an alkyl group, an alkenyl group, or an aryl group (preferable examples are the same as R _{3 to} R ₈ ), preferably represent an alkyl group or an aryl group, and more preferably represent an alkyl group. Represent. R _{23 to} R ₂₈ each independently represent hydrogen, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or a heterocyclic group (preferable examples are the same as R _{3 to} R ₈ ); And more preferably hydrogen.

In the general formula (II), Y ₁ and Y ₂ are each independently oxygen, sulfur, selenium, tellurium, —CR ₁₇ R ₁₈ —, —N
R ₁₉ - represents preferably an oxygen, sulfur, -CR ₁₇ R
₁₈ -, - NR ₁₉ -; more preferably, sulfur, -CR
₁₇ R ₁₈ —, and most preferably —CR ₁₇ R ₁₈ —. R ₁₇ , R ₁₈ and R ₁₉ are each independently hydrogen, an alkyl group, an alkenyl group or an aryl group (preferable examples are R _{3 to} R ₈
And preferably an alkyl group.

In the general formula (II), R_Fifteen, R₁₆Is German
Stands for a substituent, preferably a cyano group, an alkoxyca
Rubonyl group, carboxyl group, acyl group, acyloxy
Group, alkylsulfonyl group, arylsulfonyl group,
Sulfonic acid group, sulfonamide group, carbamoyl group,
Groups, acylamino groups, alkyl groups, alkenyl groups,
Reel group, alkoxy group, alkylthio group, arylo group
Xy, heterocyclic, phosphonyl, phosphoryl,
A droxamate group (preferred examples are R_Ten, R₁₁ Same as
), Hydroxyl group, alkynyl group (preferably C number
2-20, for example ethynyl, 2-phenylethynyl),
A cycloalkyl group (preferably having 3 to 20 carbon atoms, for example,
Chloropropyl, cyclopentyl, cyclohexyl), ha
Shows logen atoms (eg, fluorine, chlorine, bromine, iodine)
And preferably a cyano group, an alkoxycarbonyl group,
Ruboxyl group, acyloxy group, alkylsulfonyl
Group, arylsulfonyl group, sulfonic acid group, sulfone
A mid group, a carbamoyl group, an alkyl group, an alkenyl group,
Alkoxy, phosphonyl, phosphoryl, hydroxy
Represents succinic acid group, hydroxyl group, halogen atom, and more
Preferably cyano group, alkoxycarbonyl group, carbo
Xyl group, alkylsulfonyl group, arylsulfonyl
Group, sulfonic acid group, sulfonamide group, carbamoyl
Group, alkyl group, alkenyl group, alkoxy group, phospho
Nyl group, phosphoryl group, hydroxyl group, halogen atom
Represents

In the general formula (II), a and b each independently represent an integer of 0 to 4, more preferably an integer of 1 to 4. When a is 2 or more, R ₁₅ may be the same or different, and may be linked to each other to form a ring. When b is 2 or more, R ₁₆ may be the same or different, and may combine with each other to form a ring. The ring formed by connecting R _{15 to} each other and R _{16 to} each other is preferably a benzene ring.

Further, the dye represented by the general formula (I) is more preferably represented by the general formula (III). In the general formula (III), R ₂ , R ₁₃ , R ₁₄ , R _{23 to} R ₂₈ , Y ₁ , Y ₂ ,
a, b, m, and W ₁ have the same meanings as in formula (II).

In the general formula (III), R ₂₁ represents any one of oxygen, sulfur, selenium, tellurium, ＮＲNR ₉ , ＣＲCR ₃₁ R ₃₂ , preferably oxygen, sulfur, ＮＲNR ₉ , ＣＲCR ₃₁ R is preferably _32, oxygen, and more preferably = CR ₃₁ R _32. R ₉ is the general formula (I) in R ₉ synonymous with hydrogen, an alkyl group, an aryl group, an alkyl group is more preferable.

R ₃₁ and R ₃₂ each independently represent a cyano group, an alkoxycarbonyl group, a carboxyl group, an acyl group, an acyloxy group, a thioacylthio group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonic acid group, a sulfonamide group, a carbamoyl group, Amino group, acylamino group,
Alkyl group, alkenyl group, aryl group, alkoxy group, alkylthio group, aryloxy group, heterocyclic group,
Represents a phosphonyl group, a phosphoryl group, or a hydroxamic acid group (preferable examples are the same as R ₁₀ and R ₁₁ ), and is more preferably a cyano group, an alkoxycarbonyl group, a carboxyl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, And a carbamoyl group, a heterocyclic group and a phosphonyl group, more preferably a cyano group, an alkoxycarbonyl group, a carboxyl group, an alkylsulfonyl group and a heterocyclic group. Note that R ₃₁ and R ₃₂ may be the same or different.

R ₃₁ and R ₃₂ may be linked to each other to form a ring. At that time, it is preferable to form a 5- or 6-membered ring, a cycloalkane ring, a cycloalkene ring and a hetero ring are preferably formed, more preferably a hetero ring is formed, and a pyrazolidinedione ring and barbi Tool acid ring, thiobarbituric acid ring, isoxazolone ring, pyrazolone ring, pyridone ring, rhodanine ring, pyrrolotriazole ring, pyrazolotriazole ring, indandione ring,
It is more preferable to form a hydantoin ring, a thiohydantoin ring, a thiazolidinedione ring, an oxazolidinonethione ring, and a pyrazolidinedione ring, a pyrazolone ring, a rhodanin ring, an indandione ring, a thiazolidinedione ring,
It is more preferable to form an oxazolidinonethione ring, and it is particularly preferable to form a pyrazolidinedione ring, a pyrazolone ring and a rhodanine ring.

R ₂₉ and R ₃₀ are each independently a cyano group, an alkoxycarbonyl group, a carboxyl group, an acyl group, an acyloxy group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonic acid group, a sulfonamide group, a carbamoyl group, an amino group, Acylamino group, alkyl group, alkenyl group, aryl group, alkoxy group, alkylthio group,
Represents an aryloxy group, a heterocyclic group, a phosphonyl group, a phosphoryl group, a hydroxamic acid group, a hydroxyl group, an alkynyl group, a cycloalkyl group, or a halogen atom (preferable examples are the same as R ₁₅ and R ₁₆ ); Alkoxycarbonyl group, carboxyl group, acyloxy group, alkylsulfonyl group, arylsulfonyl group, sulfonic acid group, sulfonamide group, carbamoyl group, alkyl group, alkenyl group, alkoxy group, phosphonyl group,
Phosphoryl group, hydroxamic acid group, hydroxyl group, represents a halogen atom, more preferably a cyano group, an alkoxycarbonyl group, a carboxyl group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonic acid group, a sulfonamide group, a carbamoyl group, an alkyl group, Alkenyl group,
Represents an alkoxy group, a phosphonyl group, a phosphoryl group, a hydroxyl group, or a halogen atom. When a is 2 or more, R ₂₉
May be the same or different, and may be connected to each other to form a ring. When b is 2 or more, R ₃₀ may be the same or different, and may combine with each other to form a ring. The ring formed by connecting R ₂₉ and R _{30 to} each other is preferably a benzene ring.

The dyes represented by the general formulas (I) to (III)
Suitable binding groups (interlocki) for the surface of the semiconductor fine particles
ng group). Preferred linking groups include carboxyl (COO
H) group, sulfonic acid (SO ₃ H) group, phosphonyl (eg -P
An (O) (OH) ₂ ) group, a phosphoryl (eg, -OP (O) (OH) ₂ ) group,
Hydroxyl group, hydroxamic acid group (for example, -CONHOH,
—CON (CH ₃ ) OH) or a chelating group having π conductivity such as oxime, dioxime, hydroxyquinoline, salicylate and α-keto enolate. No.
These groups may form a salt with an alkali metal or the like, or may form an inner salt. General formula (I)
The dyes represented by (III) more preferably have an acidic group, and further preferably have a carboxyl group, a phosphoryl group, a phosphonyl group, and a sulfonic acid group. These acidic groups are represented by R _{9 to} R in the general formula (I).
₁₂ , P ₁ or P ₂ , and in the general formula (II), R
It is preferably contained in any of _{9 to} R ₁₂ and R _{13 to} R ₁₆ , and in general formula (III), any of R ₉ , R _{12 to} R ₁₄ and R _{29 to} R ₃₂ .

Hereinafter, specific examples of the compound represented by formula (I) of the present invention are shown, but the present invention is not limited thereto. In addition, the structural formula of the dye described herein is only the ultimate structure of one of many possible resonance structures.

[0037]

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[0038]

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[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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The synthesis of the compound represented by the general formula (I) used in the present invention is carried out according to Ukrainskii Khimicheskii Zhurnal.
Vol. 40, No. 3, pages 253-258, Chem. Ber., 92, 1809, (19
59), Tetrahedoron Lett., 41, 5341, (1985) and the references cited therein.

The general method for synthesizing the dye of the present invention is shown below, but the present invention is not limited thereto.

[0047]

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[0048]

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The dye of the present invention can be generally synthesized by the following method. As shown in Scheme 1, first, the aldehyde 2 was reacted by a Vilsmeier reaction of methylene base 1 (phosphorus oxychloride-dimethylformamide).
Is synthesized, and 3 is synthesized by reaction with a methyl Grignard reagent (CH ₃ MgI) in ether. next,
The quaternary salt 4 and diethyl squarate 5 are refluxed in a solvent such as ethanol in the presence of a base such as triethylamine to hydrolyze the terminal ethyl squarate 6 with a base such as sodium hydroxide to synthesize terminal squaric acid 7. The dye 8 of the present invention can be synthesized by a method of refluxing in a protic solvent such as butanol or ethanol together with the dye No. 3. X ^1- of 4 in Scheme 1 represents a counter anion.

In the dye of the general formula (I), R ₁ is CR ₁₀ R ₁₁
In the case of synthesizing the dye represented by the formula (1), a method using R ₁₀ CH ₂ R ₁₁ (9) as a raw material as shown in Scheme 2 is preferable, and these are generally called active methylene compounds and have a wide variety of raw materials for reaction. Is preferable. Further, a so-called "4-equivalent coupler" known in silver salt photography can also be used, which is preferable. This method is also preferable because it can be applied to the case where R ₁₀ and R ₁₁ are linked to form a ring. At that time, the dye of the general formula (I) generally has a terminal ethyl squarate 6 and an active methylene compound R ₁₀ CH ₂ R
₁₁ Substituted terminal squaric acid 10 obtained by reacting (9) in a solvent such as butanol or ethanol in the presence of a base such as sodium methoxide, potassium t-butoxide, triethylamine, potassium carbonate or the like in an equivalent amount or more.
Can be synthesized by a method of refluxing in a protic solvent such as butanol and ethanol together with 3.

Next, the structure and material of the photoelectric conversion material and the photoelectric conversion element of the present invention will be described in detail. In the present invention, the photoelectric conversion material has a semiconductor and a dye for sensitizing the semiconductor. The semiconductor used for photoelectric conversion is a so-called photoconductor,
It absorbs light and separates charges to generate electrons and holes. In a dye-sensitized semiconductor, light absorption and the resulting generation of electrons and holes mainly occur in the dye, and the semiconductor is responsible for receiving and transmitting the electrons.

In the present invention, the dye-sensitized photoelectric conversion element comprises a conductive support, a semiconductor film (photosensitive layer) sensitized by a dye provided on the conductive support, a charge transfer layer, and a counter electrode. Here, the above photoelectric conversion material is used for a semiconductor film sensitized by a dye, that is, a photosensitive layer. A photocell that can use this photoelectric conversion element for a battery to work in an external circuit is a photocell. The photosensitive layer is designed according to the purpose, and may have a single-layer structure or a multilayer structure. Light incident on the photosensitive layer excites a dye or the like. The excited dye or the like has high-energy electrons. The electrons are transferred from the dye or the like to the conduction band of the semiconductor fine particles, and reach the conductive support by diffusion. At this time, molecules such as dyes are oxidized. In a photovoltaic cell, electrons on a conductive support return to an oxidized substance such as a dye through a counter electrode and a charge transfer layer while working in an external circuit, and the dye or the like is regenerated. The semiconductor film functions as a negative electrode of this battery. In the present invention, at the boundary between the layers (for example, the boundary between the conductive layer and the photosensitive layer of the conductive support, the boundary between the photosensitive layer and the charge transfer layer, the boundary between the charge transfer layer and the counter electrode, etc.), the constituent components of each layer They may be mutually diffused and mixed.

As the semiconductor, in addition to a simple semiconductor such as silicon or germanium, a III-V compound semiconductor, a metal chalcogenide (eg, oxide, sulfide, selenide, or the like), a compound having a perovskite structure, or the like is used. be able to. Preferably as a metal chalcogenide titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium or tantalum oxide, cadmium, zinc, lead, silver,
Examples include antimony, sulfide of bismuth, cadmium, selenide of lead, and telluride of cadmium. Examples of the compound semiconductor include phosphides such as zinc, gallium, indium, and cadmium, gallium arsenide, copper-indium-selenide, and copper-indium-sulfide. Further, as the compound having a perovskite structure, strontium titanate, calcium titanate, sodium titanate, barium titanate, and potassium niobate are preferably exemplified.

[0054] More preferred as a semiconductor used in the present invention.
Specifically, specifically, Si, TiO_Two, Sn O_Two, Fe_TwoO_Three, WO_Three, Zn
O, Nb_TwoO_Five, CdS, ZnS, PbS, Bi_TwoS_Three, CdSe, CdTe, GaP, I
nP, GaAs, CuInS_Two, CuInSe_TwoIs mentioned. Even more preferred
Or TiO_Two, ZnO, SnO_Two, Fe_TwoO_Three , WO_Three, Nb_TwoO_Five, CdS, Pb
S, CdSe, InP, GaAs, CuInS_Two, CuInSe_TwoEspecially good
Preferably, TiO_TwoOr Nb_TwoO_FiveAnd most preferably TiO
_TwoIt is.

The semiconductor used in the present invention may be single crystal or polycrystal. Although a single crystal is preferable as the conversion efficiency, a polycrystal is preferable in terms of manufacturing cost, securing of raw materials, energy payback time, and the like, and a fine particle semiconductor having a nanometer to micrometer size is particularly preferable.

The particle size of these semiconductor fine particles is preferably 5 to 200 nm as a primary particle as an average particle size using the diameter when the projected area is converted into a circle, and particularly preferably 8 to 1 nm.
Preferably it is 00 nm. The average particle size of the semiconductor fine particles (secondary particles) in the dispersion is 0.01 to 10
It is preferably 0 μm.

Further, two or more kinds of fine particles having different particle size distributions may be mixed and used. In this case, the average size of the small particles is preferably 5 nm or less. Also, in order to improve the light capture rate by scattering incident light,
Semiconductor particles having a large particle size, for example, about 300 nm may be mixed.

The method for producing the semiconductor fine particles is described in Sol-gel described in "Sol-gel method science" by Agaku Shofusha (1988) by Sakubana Suzuka and "Thin-film coating technique by sol-gel method" (1995) by Technical Information Association. Tadao Sugimoto, "Synthesis of Monodisperse Particles and Size Morphology Control by New Synthetic Gel-Sol Method" Materia, Vol. 35, No. 9, 1012
The gel-sol method described on pages 10 to 1018 (1996) is preferred.

Further, a method developed by Degussa to produce an oxide by high-temperature hydrolysis of chloride in an oxyhydrogen flame is also preferable.

In the case of titanium oxide, the above-mentioned sol-gel method, gel-sol method, and high-temperature hydrolysis method of chloride in an oxyhydrogen flame are all preferable. 1997) can also be used.

In the case of titanium oxide, among the sol-gel methods described above, in particular, "Journal of American
Ceramic Society Vol. 80, No. 12, 31
Pages 57 to 3171 (1997) "and Burnside et al.," Chemical Materials Vol. 10, No. 9, pages 2419 to 2425 "
The described method is preferred.

As the conductive support, use is made of a support such as a metal which has conductivity, or a glass or plastic support having a conductive layer (conductive layer) containing a conductive agent on the surface. Can be. In the latter case, preferred conductive agents include metals (for example, platinum, gold, silver, copper, aluminum, rhodium, indium, etc.), carbon, or conductive metal oxides (indium-tin composite oxide, tin oxide doped with fluorine). And the like). The conductive agent layer preferably has a thickness of about 0.02 to 10 μm.

The lower the surface resistance of the conductive support, the better. The preferred range of the surface resistance is 100 Ω / □ or less, and more preferably 40 Ω / □ or less. The lower limit is not particularly limited, but is usually about 0.1 Ω / □.

Preferably, the conductive support is substantially transparent. Substantially transparent means that the light transmittance is 10%
The above means that it is preferably at least 50%, particularly preferably at least 70%. As the transparent conductive support, a support obtained by coating a conductive metal oxide on glass or plastic is preferable. Of these, conductive glass in which a conductive layer made of tin dioxide doped with fluorine is deposited on a transparent substrate made of low-cost soda-lime float glass is particularly preferable. Further, it is preferable to use a transparent polymer film provided with the above conductive layer for a low-cost flexible photoelectric conversion element or solar cell.
Transparent polymer films include tetraacetyl cellulose (TAC), polyethylene terephthalate (PET),
Polyethylene naphthalate (PEN), syndioctatic polysterene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC), polyarylate (PAr), polysulfone (PSF), polyester sulfone (PES), polyetherimide (PE
I), cyclic polyolefin, brominated phenoxy and the like. When a transparent conductive support is used, it is preferable that light is incident from the support side. In this case, the coating amount of the conductive metal oxide is preferably 0.01 to 100 g per 1 m ² of a glass or plastic support.

It is preferable to use a metal lead for the purpose of lowering the resistance of the transparent conductive substrate. The material of the metal lead is preferably a metal such as aluminum, copper, silver, gold, platinum, and nickel, and particularly preferably aluminum and silver. It is preferable that the metal lead is provided on a transparent substrate by vapor deposition, sputtering, or the like, and a transparent conductive layer made of tin oxide doped with fluorine or an ITO film is provided thereon. It is also preferable to provide a metal lead on the transparent conductive layer after providing the transparent conductive layer on a transparent substrate. The decrease in the amount of incident light due to the installation of metal leads is 1 to 10%, more preferably 1 to 5%.
It is.

The method of applying the semiconductor fine particles on the conductive support includes a method of applying a dispersion or colloidal solution of the semiconductor fine particles on the conductive support, and the above-mentioned sol-gel method. In consideration of mass production of photoelectric conversion elements, liquid physical properties, and flexibility of a support, a wet film forming method is relatively advantageous. As a wet type film applying method, a coating method and a printing method are typical.

As a method for preparing a dispersion of semiconductor fine particles, in addition to the above-mentioned sol-gel method, a method of grinding with a mortar, a method of dispersing while grinding using a mill, or a method of synthesizing a semiconductor in a solvent when synthesizing a semiconductor. A method of precipitating it as fine particles and using it as it is, may be mentioned. Examples of the dispersion medium include water and various organic solvents (eg, methanol, ethanol, isopropyl alcohol, dichloromethane, acetone, acetonitrile, ethyl acetate, etc.). When dispersing,
If necessary, a polymer, a surfactant, an acid, a chelating agent or the like may be used as a dispersing aid.

The application method includes a roller method and a dipping method as an application system, an air knife method and a blade method as a metering system.
No. 4,589,294, U.S. Pat. No. 2,761,419, and U.S. Pat.
A slide hopper method, an extrusion method, a curtain method and the like described in US Pat. As a general-purpose machine, a spin method or a spray method is also preferably used.

As the wet printing method, three types of printing methods, namely, relief printing, offset printing and gravure printing, intaglio printing, rubber printing, screen printing and the like have been conventionally preferred.

From the above methods, a preferable film forming method is selected according to the liquid viscosity and the wet thickness.

The viscosity of the liquid greatly depends on the type and dispersibility of the semiconductor fine particles, the type of solvent used, and additives such as a surfactant and a binder. High viscosity liquid (for example, 0.01 to 500 Po
In ise), an extrusion method or a casting method is preferable, and in a low-viscosity liquid (for example, 0.1 Poise or less), a slide hopper method, a wire bar method, or a spin method is preferable, and a uniform film can be formed.

In the case of applying a low-viscosity liquid by the extrusion method, the application is possible as long as the application amount is a certain amount.

Screen printing is often used for applying a high-viscosity paste of semiconductor fine particles, and this method can also be used.

As described above, the method of applying the wet film may be appropriately selected according to the parameters such as the liquid viscosity of the coating liquid, the coating amount, the support, and the coating speed.

Further, the semiconductor fine particle containing layer need not be limited to a single layer. It is also possible to apply a multi-layer coating of dispersion liquids having different particle diameters, and different types of semiconductors.
Alternatively, the coating layers having different compositions of the binder and the additives can be applied in multiple layers, and the multilayer coating is effective even when the film thickness is insufficient by one application. The extrusion method or the slide hopper method is suitable for multilayer coating. In the case of multi-layer coating, multi-layer coating may be performed at the same time, or several to dozens of times may be sequentially applied. Furthermore, a screen printing method can also be preferably used in the case of successive coating.

In general, as the thickness of the layer containing semiconductor fine particles increases, the amount of dye carried per unit projected area increases, so that the light capture rate increases. However, the diffusion distance of generated electrons increases, so that the loss due to charge recombination also increases. growing. Therefore, the semiconductor fine particle-containing layer has a preferable thickness, but typically has a thickness of 0.1 to 100 μm. When used as a photovoltaic cell, the thickness is preferably 1 to 30 μm,
It is more preferable that the thickness be 25 μm. The coating amount per support 1 m ² of the semiconductor fine particles 0.5～400G, more 5~100g is preferred.

The semiconductor fine particles are preferably subjected to a heat treatment after they are applied to the conductive support, in order to bring the particles into electronic contact with each other, and to improve the strength of the coating film and the adhesion to the support. The preferred range of the heat treatment temperature is 40 ° C. or more and less than 700 ° C., more preferably 1 ° C.
It is not less than 00 ° C and not more than 600 ° C. The heat treatment time is 1
It is about 0 minutes to 10 hours. When a support having a low melting point or softening point, such as a polymer film, is used, high-temperature treatment is not preferable because it causes deterioration of the support. It is preferable that the temperature is as low as possible from the viewpoint of cost. The lowering of the temperature can be achieved by the above-mentioned combination of small semiconductor particles of 5 nm or less, heat treatment in the presence of a mineral acid, and the like.

After the heat treatment, chemical plating using, for example, an aqueous solution of titanium tetrachloride for the purpose of increasing the surface area of the semiconductor particles, increasing the purity near the semiconductor particles, and increasing the efficiency of electron injection from the dye into the semiconductor particles. Alternatively, an electrochemical plating process using an aqueous solution of titanium trichloride may be performed.

The semiconductor fine particles preferably have a large surface area so that many dyes can be adsorbed. Therefore, the surface area when the semiconductor fine particle layer is coated on the support is preferably at least 10 times, more preferably at least 100 times the projected area. The upper limit is not particularly limited, but is usually about 1000 times.

The method of adsorbing the dye on the semiconductor fine particles can be carried out by immersing the working electrode containing the semiconductor particles which are well dried in the dye solution, or by applying the dye solution to the semiconductor fine particle layer and adsorbing it. . In the former case, a dipping method, a dipping method, a roller method, an air knife method, or the like can be used. The latter coating method includes a wire bar method, a slide hopper method, an extrusion method, a curtain method, a spin method, and a spray method, and the printing method includes letterpress, offset, gravure, screen printing, and the like. The solvent can be appropriately selected according to the solubility of the dye. For example, alcohols (methanol, ethanol, t-butanol, benzyl alcohol, etc.), nitriles (acetonitrile, propionitrile, 3-methoxypropionitrile, etc.), nitromethane, halogenated hydrocarbons (dichloromethane, dichloroethane, chloroform, chlorobenzene) ), Ethers (eg, diethyl ether, tetrahydrofuran), dimethyl sulfoxide, amides (eg, N, N-dimethylformamide, N, N-dimethylacetamide), N-methylpyrrolidone, 1,3-dimethylimidazolidinone , 3-methyloxazolidinone, esters (ethyl acetate, butyl acetate, etc.), carbonates (diethyl carbonate, ethylene carbonate, propylene carbonate, etc.), ketones (acetone, 2-butanone, cyclohexanone, etc.), hydrocarbons Hexane, petroleum ether, benzene, toluene, etc.) or mixed solvents thereof.

As in the case of the formation of the semiconductor fine particle layer, the viscosity of the liquid is the same as that for the formation of the semiconductor fine particle layer. In addition to the extrusion method for a high-viscosity liquid (for example, 0.01 to 500 Poise), various printing methods are used. A slide hopper method, a wire bar method, or a spin method is suitable, and a uniform film can be obtained.

As described above, the viscosity of the dye coating solution, the coating amount,
An application method may be appropriately selected according to parameters such as a support and a coating speed. The time required for dye adsorption after coating should be as short as possible in consideration of mass production.

Since the presence of unadsorbed dye causes disturbance of device performance, it is preferable to remove the dye by washing immediately after adsorption. It is preferable to perform cleaning with a polar solvent such as acetonitrile and an organic solvent such as an alcohol solvent using a wet cleaning tank. Further, in order to increase the amount of the adsorbed dye, it is preferable to perform the heat treatment before the adsorption. After the heat treatment, in order to avoid the adsorption of water on the surface of the semiconductor fine particles, it is also preferable to quickly adsorb the dye at 40 to 80 ° C. without returning to normal temperature.

The total amount of the dye used is preferably 0.01 to 100 mmol per 1 m ² of the support. The amount of the dye adsorbed on the semiconductor fine particles is preferably 0.01 to 1 mmol per 1 g of the semiconductor fine particles. With such an amount of the dye, a sensitizing effect in the semiconductor can be sufficiently obtained. On the other hand, if the amount of the dye is small, the sensitizing effect becomes insufficient, and if the amount of the dye is too large, the dye not adhering to the semiconductor floats and causes a reduction in the sensitizing effect. In addition,
In the present invention, the dye of the present invention and a known dye, in order to widen the wavelength range of photoelectric conversion as much as possible and to increase the conversion efficiency,
For example, a ruthenium complex dye, an organic dye (for example, polymethine dye) and the like can be used in combination. Dyes to be mixed and their proportions can be selected so as to match the wavelength range and intensity distribution of the target light source.

A colorless compound may be co-adsorbed for the purpose of reducing interaction between dyes such as association. Examples of the hydrophobic compound to be co-adsorbed include steroid compounds having a carboxy group (for example, chenodeoxycholic acid). Further, an ultraviolet absorber can be used in combination.

For the purpose of promoting the removal of excess dye, the surface of the semiconductor fine particles may be treated with an amine after adsorbing the dye. Preferred amines include pyridine, 4-tert-butylpyridine, polyvinylpyridine and the like. When these are liquids, they may be used as they are or may be used by dissolving them in an organic solvent.

Hereinafter, the charge transfer layer and the counter electrode will be described in detail. The charge transfer layer is a layer having a function of replenishing an oxidized dye with electrons. Examples of typical charge transfer layers that can be used in the present invention include a liquid in which a redox couple is dissolved in an organic solvent (electrolyte solution) and a so-called gel in which a liquid in which a redox couple is dissolved in an organic solvent is impregnated in a polymer matrix. Examples of the electrolyte include an electrolyte and a molten salt containing a redox couple.
Further, a solid electrolyte or a hole transporting material can be used.

The electrolyte used in the present invention comprises an electrolyte, a solvent,
And additives. The electrolyte of the present invention is LiI as a combination (iodides I ₂ and an iodide, NaI, KI, CsI, metal iodide such as CaI ₂ or tetraalkylammonium iodide, pyridinium iodide, imidazolium iodide, etc. 4 Iodine salts of quaternary ammonium compounds), Br
Combination of ₂ and bromide (bromide is LiBr, N
ABR, KBr, CsBr, metal bromide such as CaBr ₂ or tetraalkylammonium bromide,
Bromide salts of quaternary ammonium compounds such as pyridinium bromide), metal complexes such as ferrocyanate-ferricyanate and ferrocene-ferricinium ions, sulfur compounds such as sodium polysulfide and alkylthiol-alkyldisulfide, and viologen Dyes, hydroquinone-quinone and the like can be used. I ₂ and LiI or pyridinium iodide Among these, an electrolyte that combines iodine salt of imidazolium iodide and quaternary ammonium compounds are preferred in the present invention. The above-mentioned electrolytes may be used as a mixture. The electrolyte is EP-718
No.288, WO95 / 18456, J. Electrochem.Soc., Vol.14
3, No. 10, 3099 (1996), Inorg. Chem. 1996, 35, 1168-1178
The salt in a molten state at room temperature (molten salt) described in (1) can also be used. When a molten salt is used as an electrolyte, a solvent need not be used.

The preferred electrolyte concentration is 0.1 M or more and 15 M or less, more preferably 0.2 M or more and 10 M or less. In addition, when iodine is added to the electrolyte, the preferable concentration of iodine is 0.01M or more and 0.5M or less.

The solvent used for the electrolyte in the present invention is a compound capable of exhibiting excellent ionic conductivity by lowering the viscosity and improving the ionic mobility or increasing the dielectric constant and improving the effective carrier concentration. Desirably. Examples of such a solvent include carbonate compounds such as ethylene carbonate and propylene carbonate, 3-methyl-
Heterocyclic compounds such as 2-oxazolidinone, dioxane, ether compounds such as diethyl ether, ethylene glycol dialkyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, chain ethers such as polypropylene glycol dialkyl ether, methanol, ethanol,
Alcohols such as ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, polyethylene glycol monoalkyl ether, and polypropylene glycol monoalkyl ether; polyhydric alcohols such as ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, and glycerin; acetonitrile; Nitrile compounds such as glutaronitrile, methoxyacetonitrile, propionitrile, and benzonitrile; aprotic polar substances such as dimethylsulfoxide (DMSO) and sulfolane; and water can be used.

In the present invention, J. Am. Ceram. Soc.,
80 (12) 3157-3171 (1997), ter-butylpyridine, and basic compounds such as 2-picoline and 2,6-lutidine can also be added. The preferred concentration range when adding a basic compound is 0.05M or more and 2M or less.

In the present invention, the electrolyte may be gelled (solidified) by a method such as addition of a polymer, addition of an oil gelling agent, polymerization containing a polyfunctional monomer, and crosslinking reaction of the polymer. When gelling by adding a polymer, use the Polymer Electrolyte Review-1 and 2
(Co-edited by JR MacCallum and CA Vincent, ELSEVIER APPLI
Compounds described in ED SCIENCE) can be used, and particularly, polyacrylonitrile and polyvinylidene fluoride can be preferably used. When gelling by adding an oil gelling agent, use J. Chem Soc. Japan, Ind.
Chem.Sec., 46, 779 (1943), J. Am. Chem. Soc., 111,
5542 (1989), J. Chem. Soc., Chem. Commun., 1993, 3
90, Angew. Chem. Int. Ed. Engl., 35, 1949 (1996), Ch.
em. Lett., 1996, 885, J. Chm. Soc., Chem. Commun.,
Although the compounds described in 1997,545 can be used, preferred compounds are compounds having an amide structure in the molecular structure.

When the gel electrolyte is formed by polymerization of polyfunctional monomers, a solution is prepared from the polyfunctional monomers, a polymerization initiator, an electrolyte, and a solvent, and the solution is prepared by a method such as a casting method, a coating method, a dipping method, or an impregnation method. A method in which a sol-like electrolyte layer is formed on an electrode supporting a dye and then gelled by radical polymerization is preferable. The polyfunctional monomer is preferably a compound having two or more ethylenically unsaturated groups, for example, divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and triethylene glycol dimethacrylate. Ethylene glycol diacrylate, triethylene glycol dimethacrylate,
Preferred examples include pentaerythritol triacrylate and trimethylolpropane triacrylate. The monomers constituting the gel electrolyte may include a monofunctional monomer in addition to the above, and may include acrylic acid or α-
Esters or amides derived from alkylacrylic acids (such as methacrylic acid) (such as Nis
o-propylacrylamide, acrylamide, 2-acrylamide-2-methylpropanesulfonic acid, acrylamidopropyltrimethylammonium chloride,
Methyl acrylate, hydroxyethyl acrylate,
n-propyl acrylate, n-butyl acrylate,
2-methoxyethyl acrylate, cyclohexyl acrylate, etc.), vinyl esters (eg, vinyl acetate), esters derived from maleic acid or fumaric acid (eg, dimethyl maleate, dibutyl maleate, diethyl fumarate, etc.), maleic acid, Fumaric acid,
p-styrenesulfonic acid sodium salt, acrylonitrile, methacrylonitrile, dienes (eg, butadiene, cyclopentadiene, isoprene), aromatic vinyl compound (eg, styrene, p-chlorostyrene, sodium styrenesulfonate), nitrogen-containing heterocycle A vinyl compound having a quaternary ammonium salt,
N-vinylformamide, N-vinyl-N-methylformamide, vinyl sulfonic acid, sodium vinyl sulfonate, vinylidene fluoride, vinylidene chloride, vinyl alkyl ethers (eg, methyl vinyl ether), ethylene, propylene, 1-butene, isobutene, N-phenylmaleimide and the like can be preferably used. The preferred weight composition range of the polyfunctional monomer in the total amount of the monomers is preferably from 0.5% by weight to 70% by weight, more preferably from 1.0% by weight to 50% by weight.
% By weight or less.

The above-mentioned monomers are generally described in Takatsu Otsu and Masayoshi Kinoshita: Experimental Methods for Polymer Synthesis (Chemical Doujin) and Takatsu Otsu: Lecture Polymerization Reaction Theory 1 Radical Polymerization (I) (Chemical Doujin) It can be polymerized by radical polymerization, which is a simple polymer synthesis method. The monomer for a gel electrolyte that can be used in the present invention can be radically polymerized by heating, light, electron beam, or electrochemically, but it is particularly preferable to radically polymerize by heating. The polymerization initiator preferably used when the crosslinked polymer is formed by heating,
For example, 2,2'-azobisisobutyronitrile, 2,2
2'-azobis (2,4-dimethylvaleronitrile),
Azo initiators such as dimethyl 2,2'-azobis (2-methylpropionate) (dimethyl 2,2'-azobisisobutyrate); and peroxide initiators such as benzoyl peroxide. The preferred amount of the polymerization initiator is from 0.01% by weight to 20% by weight, more preferably from 0.1% by weight to 10% by weight, based on the total amount of the monomers.
It is as follows.

The weight composition range of the monomers in the gel electrolyte is preferably 0.5% by weight or more and 70% by weight or less, more preferably 1.0% by weight or more and 50% by weight or less.

When the electrolyte is gelled by a crosslinking reaction of the polymer, it is desirable to use a polymer having a crosslinkable reactive group and a crosslinking agent together. In this case, a preferable crosslinkable reactive group is a nitrogen-containing heterocyclic ring (for example, a pyridine ring, an imidazole ring, a thiazole ring, an oxazole ring, a triazole ring, a morpholine ring, a piperidine ring, a piperazine ring, etc.), and a preferable crosslinking agent. Is a bifunctional or higher functional reagent capable of electrophilic reaction with a nitrogen atom (for example, alkyl halide, aralkyl halide, sulfonic acid ester, acid anhydride, acid chloride, isocyanate, etc.).

In the present invention, an organic or inorganic material or a hole transporting material combining the both can be used instead of the electrolyte. Organic hole transport materials applicable to the present invention include N, N'-diphenyl-N, N'-bis (4-methoxyphenyl)-(1,1'-biphenyl) -4,4'-diamine
(J. Hagen et al., Synthetic Metal 89 (1997) 215-22
0), 2,2 ', 7,7'-tetrakis (N, N-di-p-methoxyphenylamine) 9,9'-spirobifluorene (Nature, Vol. 395,
8 Oct. 1998, p583-585 and WO97 / 10617), aromatic diamine compounds linked to tertiary aromatic amine units of 1,1-bis {4- (di-p-tolylamino) phenyl} cyclohexane 59-194393), two or more fused aromatic rings containing two or more tertiary amines represented by 4,4-bis [(N-1-naphthyl) -N-phenylamino] biphenyl Aromatic amine substituted with a nitrogen atom (JP-A-5
-234681), an aromatic triamine having a starburst structure as a derivative of triphenylbenzene (US Pat. No. 4,923,774, JP-A-4-308688), N, N'-diphenyl-N, N Aromatic diamines such as' -bis (3-methylphenyl)-(1,1'-biphenyl) -4,4'-diamine (US Pat. No. 4,764,625), α, α, α ′, α '-Tetramethyl-α, α'-bis (4-di-p-tolylaminophenyl) -p-
Xylene (JP-A-3-269084), p-phenylenediamine derivative, triphenylamine derivative which is sterically asymmetric as a whole molecule (JP-A-4-129271), and a pyrenyl group substituted with a plurality of aromatic diamino groups (JP-A-4-175395) and an aromatic diamine in which a tertiary aromatic amine unit is linked by an ethylene group (JP-A-4-264189).
JP-A-5-25473), an aromatic diamine having a styryl structure (JP-A-4-290851), a benzylphenyl compound (JP-A-4-364153), and a tertiary amine linked by a fluorene group (JP-A-5-25473). JP-A-5-239455), a triamine compound (JP-A-5-239455), a pisdipyridylaminobiphenyl (JP-A-5-320634), an N, N, N-triphenylamine derivative (JP-A-6-1972), Aromatic diamines having a phenoxazine structure (JP-A-7-13856)
No. 2), aromatic amines such as diaminophenylphenanthridine derivatives (JP-A-7-252474), α-octylthiophene and α, ω-dihexyl-α-octylthiophene (Adv. Mater. 1997, 9, N0.7, p557), hexadodecyldodecithiophene (Angew.Chem.Int.Ed.Eng.
l. 1995, 34, No. 3, p303-307), 2,8-dihexyl anthra [2,3-b: 6,7-b '] dithiophene (JACS, Vol120, N0.4,199
Oligothiophene compounds such as polypyrrole (K. Murakoshi et al.,; Chem. Lett. 1997, p47).
1) 、 ¨Handbook of Organic Conductive Molecules an
d Polymers Vol.1,2,3,4¨ (by NALWA, published by WILEY), polyacetylene and its derivatives, poly (p
-Phenylene) and its derivatives, poly (p-phenylenevinylene) and its derivatives, polythienylenevinylene and its derivatives, polythiophene and its derivatives,
Conductive polymers such as polyaniline and its derivatives, polytoluidine and its derivatives can be preferably used. Natur is used as the organic hole transport material.
e, Vol. 395, 8 Oct. 1998, p583-585. To control dopant levels, compounds containing cation radicals such as tris (4-bromophenyl) aminium hexachloroantimonate were used. A salt such as Li [(CF ₃ SO ₂ ) ₂ N] may be added for controlling the potential of the oxide semiconductor surface (compensating for the space charge layer).

The organic hole transporting material can be introduced into the inside of the electrode by a method such as a vacuum evaporation method, a casting method, a coating method, a spin coating method, an immersion method, an electrolytic polymerization method, and a photoelectrolytic polymerization method. When a hole transport material is used in place of the electrolyte, it is used to prevent a short circuit. Electorochim. Acta 40, 643-652
(1995), it is preferable to apply a thin layer of titanium dioxide as an undercoat layer using a technique such as spray pyrolysis.

When an inorganic solid compound is used instead of the electrolyte, copper iodide (p-CuI) (J. Phys. D: Appl. Phys. 31
(1998) 1492-1496), copper thiocyanate (Thin Solid Film)
s 261 (1995) 307-310, J. Appl. Phys. 80 (8), 15 Octobe
r 1996, p4749-4754, Chem. Mater. 1998, 10, 1501-150.
9, Semicond. Sci. Technol. 10, 1689-1693) can be introduced into the inside of the electrode by a method such as a casting method, a coating method, a spin coating method, a dipping method, and an electrolytic plating method.

There are two methods for forming the charge transfer layer. One is a method in which a counter electrode is first stuck on a semiconductor fine particle-containing layer carrying a sensitizing dye, and a liquid charge transfer layer is sandwiched in the gap. Another one
One is to apply the charge transfer layer directly on the semiconductor fine particle-containing layer, and the counter electrode is applied thereafter.

As the method of sandwiching the charge transfer layer in the former case, a normal pressure process utilizing a capillary phenomenon due to immersion or the like and a vacuum process of replacing the gas phase with a liquid phase at a pressure lower than normal pressure can be used.

In the latter case, the wet charge transfer layer is provided with a counter electrode in an undried state, and measures are taken to prevent liquid leakage at the edge. In the case of a gel electrolyte, there is also a method of applying it by a wet method and solidifying it by a method such as polymerization. In this case, a counter electrode can be provided after drying and fixing. As a method for applying a wet organic hole transport material or a gel electrolyte in addition to the electrolytic solution, the immersion method, the roller method, the dipping method, the air knife method, the extrusion method, and the slide method are the same as the method for applying the semiconductor fine particle-containing layer and the dye. A hopper method, a wire bar method, a spin method, a spray method, a casting method, various printing methods and the like can be considered. In the case of a solid electrolyte or a solid hole (hole) transport material, the charge transfer layer can be formed by a dry film forming process such as a vacuum evaporation method or a CVD method, and then a counter electrode can be provided.

In consideration of mass production, in the case of an electrolyte which cannot be solidified or a wet hole transport material, it is possible to cope by sealing the edge portion immediately after coating, but it is possible to solidify. In the case of a hole transport material, it is more preferable to solidify the layer by a method such as photopolymerization or thermal radical polymerization after forming the hole transport layer by wet application. As described above, the film application method may be appropriately selected depending on the physical properties of the liquid and the process conditions.

The water content in the charge transfer layer was 10,
2,000 ppm or less, more preferably 2,0 ppm
It is at most 00 ppm, particularly preferably at most 100 ppm.

The counter electrode functions as a positive electrode of the photovoltaic cell when the photoelectric conversion element is a photovoltaic cell. As the counter electrode, a support having a conductive layer can be used as in the case of the above-described conductive support. However, the support is not necessarily required in a configuration in which the strength and the sealing property are sufficiently maintained. Specifically, the conductive material used for the counter electrode is a metal (for example, platinum,
Gold, silver, copper, aluminum, rhodium, indium, etc., carbon, or conductive metal oxide (indium-
Tin composite oxide, tin oxide doped with fluorine, etc.). The thickness of the counter electrode is not particularly limited,
It is preferably 3 nm or more and 10 μm or less. In the case of a metal material, the film thickness is preferably 5 μm or less, more preferably 5 nm or more and 3 μm or less.

In order for light to reach the photosensitive layer, at least one of the conductive support and the counter electrode must be substantially transparent. In the photovoltaic cell of the present invention, it is preferable that the conductive support is transparent and sunlight is incident from the support side. In this case, it is more preferable that the counter electrode has a property of reflecting light. In the present invention, as the counter electrode, glass or plastic on which a metal or a conductive oxide is deposited, or a metal thin film can be used.

As described in the application of the charge transfer layer, the counter electrode is applied on the charge transfer layer or first on the semiconductor fine particle-containing layer. In either case, depending on the type of counter electrode material and the type of charge transfer layer,
The counter electrode material can be appropriately formed on the charge transfer layer or the semiconductor fine particle-containing layer by a method such as coating, laminating, vapor deposition, or bonding. For example, in the case of attaching a counter electrode, a substrate provided as a conductive layer can be attached by a method such as application, evaporation, or CVD of the above conductive material. When the charge transfer layer is solid, the above-mentioned conductive material is directly applied thereon, plated, PVD, CV
The counter electrode can be formed by a technique such as D.

Further, it is also possible to provide a layer having other necessary functions such as a protective layer and an antireflection film on the conductive support or the counter electrode of the working electrode. When such layers are separated in function by multiple layers, simultaneous multilayer coating or sequential coating can be performed, but simultaneous multilayer coating is more preferable in terms of productivity. In the simultaneous multi-layer coating, the slide hopper method and the extrusion method are suitable in consideration of productivity and uniformity of film formation. In addition, these functional layers can be provided by a technique such as vapor deposition or pasting depending on the material.

In the photovoltaic cell of the present invention, it is preferable to seal the side surface of the cell with a polymer, an adhesive or the like in order to prevent deterioration of components and volatilization of contents.

Next, a cell structure and a module structure when the photoelectric conversion element of the present invention is applied to a so-called solar cell will be described.

The structure inside the cell of the dye-sensitized solar cell is as follows:
Basically, it is the same as the above-described photoelectric conversion element or photovoltaic cell, but various forms are possible according to the purpose as shown in FIG. 2 or FIG. When roughly divided into two, a structure that allows light to enter from both sides [FIGS. 2 (a), (d) and 3 (g)]
And types [FIGS. 2 (b) (c) and 3 (e) (f) (h)] that are possible only from one side.

FIG. 2A shows a dye-adsorbed TiO ₂ layer 10 which is a layer containing dye-adsorbed semiconductor fine particles between transparent conductive layers 12.
And the charge transfer layer 11. FIG.
(B), a metal lead 9 is partially provided on a transparent substrate 13;
Further, a transparent conductive layer 12 is provided, an undercoat layer 14, a dye-adsorbed TiO ₂ layer 10, a charge transfer layer 11 and a metal layer 8 are provided in this order, and a support substrate 15 is further provided.
FIG. 2 (c) shows that a metal layer 8 is further provided on a support substrate 15, a dye-adsorbed TiO ₂ layer 10 is provided via an undercoat layer 14, and a charge transfer layer 11 and a transparent conductive layer 12 are further provided.
This is a structure in which a transparent substrate 13 partially provided with a metal lead 9 is arranged with the metal lead 9 side inside. FIG. 2 (d)
Has a structure in which a metal lead 9 is partially provided on a transparent substrate 13, and an undercoat layer 14, a dye-adsorbed TiO ₂ layer 10, and a charge transfer layer 11 are interposed between a transparent conductive layer 12 and a transparent conductive layer 12. FIG. 3 (e) has a transparent conductive layer 12 on a transparent substrate 13, a dye-adsorbed TiO ₂ layer 10 is provided via an undercoat layer 14, and a charge transfer layer 11 and a metal layer 8 are further provided thereon. This is a structure in which a support substrate 15 is arranged. FIG.
(F) has a metal layer 8 on a support substrate 15, a dye-adsorbed TiO ₂ layer 10 is provided via an undercoat layer 14, a charge transfer layer 11 and a transparent conductive layer 12 are further provided, and a transparent substrate 13 is arranged. FIG. 3 (g) shows a transparent conductive layer 1 between transparent substrates 13 having a transparent conductive layer 12.
2 on the inside, the undercoat layer 14, the dye-adsorbed TiO ₂ layer 1
0 and the charge transfer layer 11 are interposed. FIG.
(H), a metal layer 8 is provided on a support substrate 15, a dye-adsorbed TiO ₂ layer 10 is provided via an undercoat layer 14, a solid charge transfer layer 16 is further provided, and a part of the metal layer 8 or This is a structure having metal leads 9.

The module structure of the dye-sensitized solar cell of the present invention can have basically the same structure as a conventional solar cell module. Generally, a cell is formed on a supporting substrate such as a metal or ceramic, and the cell is covered with a filling resin or a protective glass or the like, and light can be taken in from the opposite side of the supporting substrate. It is also possible to use a transparent material such as tempered glass for the substrate, form a cell thereon, and take in light from the transparent support substrate side. Specifically, a module structure called a superstrate type, a substrate type, or a potting type, or a module structure such as an integrated substrate type used in an amorphous silicon solar cell or the like is possible. These module structures can be appropriately selected depending on the purpose of use and the place of use (environment). FIG. 4 shows an example in which the element of the present invention is formed into a module with an integrated substrate.

The structure shown in FIG. 4 has a transparent conductive layer 12 on one surface of a transparent substrate 13, on which a dye-adsorbed Ti
A cell provided with an O ₂ layer 10, a solid charge transfer layer 16 and a metal layer 8 is modularized and comprises a transparent substrate 13.
An anti-reflection layer 17 is provided on the other surface. In this case, in order to increase the utilization efficiency of incident light, it is preferable to increase the area ratio of the dye-adsorbed TiO ₂ layer 10 as the photosensitive portion (the area ratio when viewed from the transparent substrate 13 side which is the light incident surface). preferable.

In a typical structure of a superstrate type or a substrate type, cells are arranged at a fixed interval between supporting substrates which are transparent on one or both sides and have been subjected to an antireflection treatment, and metal leads or adjacent cells are provided between adjacent cells. They are connected by a flexible wiring or the like, and have a structure in which current collecting electrodes are arranged on the outer edge to take out generated power to the outside. Various types of plastic materials such as ethylene vinyl acetate (EVA) can be used between the substrate and the cell in the form of a film or a filling resin, depending on the purpose, in order to protect the cell and increase current collection efficiency. When using in places where it is not necessary to cover the surface with a hard material, such as places where there is little external impact, make the surface protective layer a transparent plastic film or cure the above-mentioned filling and sealing material. It is also possible to provide a protection function and eliminate the support substrate on one side. The periphery of the support substrate is fixed in a sandwich shape with a metal frame in order to seal the inside and ensure the rigidity of the module, and the space between the support substrate and the frame is hermetically sealed with a sealing material.

When a flexible material is used for the cell itself, the support substrate, the filler and the sealing member, a solar cell can be formed on a curved surface. In this way, solar cells having various shapes and functions according to the purpose of use and environment of use can be manufactured.

[0117] The super straight type solar cell module is, for example, a method in which a front substrate sent from a substrate supply device is conveyed by a belt conveyor or the like, and a cell is placed thereon with a sealing material, a lead wire for connection between cells, and a back surface sealing. After laminating sequentially with materials and the like, a back substrate or a back cover can be placed, and a frame can be set on the outer edge portion to make it.

On the other hand, in the case of the substrate type, the cells are sequentially stacked together with the inter-cell connection lead wires and the sealing material while the support substrate sent out from the substrate supply device is transported by a belt conveyor or the like. It can be manufactured by placing a front cover and setting a frame on the periphery.

The module having the structure shown in FIG. 4 is formed by selective plating, selective etching, and CVD so that transparent electrodes, photosensitive layers, charge transfer layers, back electrodes, and the like are arranged three-dimensionally at regular intervals on a supporting substrate.・ Laser scribing or plasma CVM (Solar Ener) after semiconductor process technology such as PVD, or pattern application or wide application
gy Materials and Solar Cells, 48, p373-381) or a mechanical method such as grinding or the like, and a desired module structure can be obtained.

The other members and steps will be described below in detail. Examples of the sealing material include liquid-state EVA (ethylene vinyl acetate), a vinylidene fluoride copolymer and an acrylic resin mixture film-like EVA, and the like. Various materials can be used according to the purpose of improving (impact).

These are fixed on the cell according to the physical properties of the sealing material. For film-like materials, heat adhesion after roll pressing or heat adhesion after vacuum pressure, and for liquid or paste materials, roll adhesion. There are various methods such as coating, bar coating, spray coating, screen printing and the like.

Further, by incorporating a transparent filler into the sealing material, the strength can be increased and the light transmittance can be increased.

The space between the outer edge of the module and the frame surrounding the peripheral edge is preferably sealed with a resin having high weather resistance and moisture resistance.

When a flexible material such as PET or PEN is used as the support substrate, a roll-shaped support is drawn out to form a cell thereon, and then the sealing layer is continuously laminated by the above method. And a highly productive process can be made.

In order to increase the power generation efficiency, the surface of the substrate (generally tempered glass) on the light intake side of the module is subjected to an anti-reflection treatment. This includes a method of laminating an antireflection film and a method of coating an antireflection layer.

Further, by treating the surface of the cell by a method such as grooving or texturing, it is possible to increase the utilization efficiency of incident light.

In order to increase the power generation efficiency, it is most important that light is taken into the module without loss. However, light that has passed through the photoelectric conversion layer and has reached the inside thereof is reflected and efficiently returned to the photoelectric conversion layer side. It is also important. For this purpose, after mirror-polishing the surface of the supporting substrate, a method of depositing or plating Ag or Al or the like, a method of providing an alloy layer such as Al-Mg or Al-Ti as a reflective layer on the lowermost layer of the cell,
Alternatively, there is a method in which a texture structure is formed in the lowermost layer by annealing to increase the reflectance.

In order to increase the power generation efficiency, it is important to reduce the connection resistance between cells in order to suppress the internal voltage drop.

The connection is generally made by wire bonding or a conductive flexible sheet. However, a method of using a conductive adhesive tape or a conductive adhesive to have both a cell fixing function and an electric connection function, a conductive hot melt Is applied to a desired position in a pattern.

In a solar cell using a flexible support such as a polymer film, cells are sequentially formed and cut into a desired size by the method described in the description of semiconductor coating while feeding a roll-shaped support. In addition, the periphery can be sealed with a flexible and moisture-proof material to produce a battery body. Also, Solar Energy Materials andSo
LAR Cells, 48, p383-391, and a module structure called “SCAF” can also be used.

In a solar cell having a flexible support, the solar cell can be further used by being adhered and fixed to a curved glass or the like.

[0132]

The present invention will be specifically described below with reference to examples. Example 1: D-1, D-35, D-5, D-6, D-9
(1) Synthesis of D-1

[0133]

Embedded image

7.5 ml of phosphorus oxychloride (80 mm
l) is cooled to 24 ml of dry dimethylformamide and
While maintaining the temperature at 0 ° C., the solution was added dropwise, and while maintaining the temperature at 10 ° C., 13.0 g (7.5 mmol) of methylene base / 6 ml of dry dimethylformamide were added dropwise. After stirring at 35 ° C. for 45 minutes, the mixture was cooled and poured into water, and a solution of 14.3 g of sodium hydroxide / 75 ml of water was added and refluxed for 5 minutes.
After cooling, the mixture was extracted three times with ether, dried over magnesium sulfate and concentrated. Purified by silica gel column chromatography (developing solvent: ethyl acetate: hexane = 1: 1),
7.8 g (52% yield) of a viscous liquid of aldehyde 22 was obtained.

Magnesium sharpener 3.92 g (164 m
mol) and 120 ml of dry ether were stirred at room temperature,
8.52 g (60 mmol) of methyl iodide / 60 ml of dry ether were added dropwise over 40 minutes, and the mixture was further stirred at room temperature for 3 hours. Aldehyde 22, 4.40 g (22 mmo
l) / 240 ml of ether was slowly added, and the mixture was further stirred at room temperature for 30 minutes. Open it on 320 g of ice, add 240 ml of 5% ammonium chloride solution, stir, and separate.
Washed three times with water. Concentrate after drying with magnesium sulfate,
Purification was performed by silica gel column chromatography (developing solvent: ethyl acetate: hexane = 1: 10) to obtain 3.0 g of liquid 23 (69% yield).

Indolenine quaternary salt 24, 8.07 g (2
0 mmol), 3.44 g of diethyl squarate (20
mmol), 6.68 g of triethylamine (66 mmol)
l) was dissolved in 50 ml of ethanol and refluxed for 4 hours. After cooling, dilute hydrochloric acid was added to adjust the pH to 3, and the crystals were separated by filtration and washed with ethanol to obtain 4.55 g (yield: 64%) of yellow crystals of terminal ethyl squarate 25.

Ethyl terminal squarate 25, 3.55 g
(10 mmol) was dissolved in 10 ml of ethanol, and 1.2 g (30 mmol) of sodium hydroxide in 5 ml of water was added thereto, followed by refluxing for 1 hour. After cooling, add hydrochloric acid to pH 3,
The generated crystals are filtered off and washed with water, and the terminal squaric acid 26
As a result, 2.32 g (yield: 71%) of yellow crystal was obtained.

23, 0.2 g (1 mmol) and terminal squaric acid 26, 0.33 g (1 mmol) were dissolved in 5 ml of butanol and refluxed for 4 hours. After concentration, the residue was purified by silica gel column chromatography (developing solvent: methylene chloride: methanol = 10: 1), and recrystallized from ethanol to obtain 0.05 g (yield: 10%) of the objective D-1. The structure was confirmed by NMR and MS spectra.

(2) Synthesis of D-35

[0140]

Embedded image

In the synthesis of D-1 in (1), D-35 and D-35 were synthesized in exactly the same manner except that equimolar terminal squaric acid 27 was used instead of 26.
4 g were synthesized. The structure was confirmed by NMR and MS spectra.

(3) Synthesis of D-5 Ethyl squarate at terminal 28 synthesized by the same method as in 25, 1.20 g (3 mmol), malononitrile 0.22 g (3.3 mmol), sodium methoxide / methanol 28% solution 0 0.69 g (3.6 mmol)
Was dissolved in 20 ml of butanol and refluxed for 2 hours. After cooling, hydrochloric acid was added to adjust the pH to 3, and the crystals were filtered off and washed with ethanol to obtain 0.75 g of 29 orange crystals (yield: 60).
%).

29, 0.42 g (1 mmol), 23,
0.20 g (1 mmol) was dissolved in 5 ml of butanol and refluxed for 4 hours. After concentration, silica gel column chromatography (developing solvent: methylene chloride: methanol = 10:
Purification in 1) and recrystallization from ethanol yielded 0.09 g (yield 15%) of the target crystal of D-5. The structure was confirmed by NMR spectrum and MS spectrum.

(4) Synthesis of D-6 30 was obtained in exactly the same manner as in the synthesis of 29 and D-5 except that butyl cyanoacetate was used in an equimolar amount instead of malononitrile. .19 g were obtained. The structure was confirmed by NMR spectrum and MS spectrum.

(5) Synthesis of D-9

[0146]

Embedded image

In the synthesis of 29 and D-5, except that pyrazolidinedione 31 was used in an equimolar amount instead of malononitrile, 32 was obtained in exactly the same manner.
24 g were obtained. The structure was confirmed by NMR spectrum and MS spectrum.

(6): Measurement of Absorption Spectra Absorption spectra in methanol of D-1, D-2, D-5, D-6, D-9 and D-35 and Comparative Dye 1 were measured. Table 1 shows the absorption maximum wavelength.

[0149]

[Table 1]

In each case, the wavelength was at least 100 nm longer than that of Comparative Dye 1, and the maximum absorption wavelength reached an infrared region longer than 700 nm. Therefore, when used as a photochemical cell, it is very preferable because light having a longer wavelength can be spectrally sensitized and converted into a photocurrent.

Example 2 (1) Preparation of Titanium Dioxide Dispersion Internal volume 2 coated with Teflon (registered trademark)
15 g of titanium dioxide (Degussa P-25, Nippon Aerosil Co., Ltd.) and water 4 in a 00 ml stainless steel vessel
5 g, dispersant (Triton X-, manufactured by Aldrich)
100) 1 g and 30 g of zirconia beads having a diameter of 0.5 mm (manufactured by Nikkato Co., Ltd.) were added, and dispersed at 1500 rpm for 2 hours using a sand grinder mill (manufactured by Imex). The zirconia beads were removed by filtration from the dispersion. The average particle size of titanium dioxide in this case is 2.5 μm
Met. The particle size at this time was measured with a master sizer manufactured by MALVERN.

(2) Preparation of TiO ₂ Electrode Adsorbing Dye Conductive surface of conductive glass coated with fluorine-doped tin oxide (TCO glass-U manufactured by Asahi Glass cut into a size of 20 mm × 20 mm) The dispersion was applied to the side using a glass rod. At this time, adhesive tape is applied to a part (3 mm from the end) on the conductive surface side as a spacer,
Arrange the glass so that the adhesive tape is
It was applied one by one. After application, the adhesive tape was peeled off and air-dried at room temperature for one day. Next, this glass was placed in an electric furnace (muffle furnace FP-32 manufactured by Yamato Scientific Co., Ltd.) and heated at 450 ° C. for 3 hours.
After baking for 0 minutes, a TiO ₂ electrode was obtained. After the electrode was taken out and cooled, it was immersed in a methanol solution of the dye shown in Table 1 (each dye was 3 × 10 ^-4 mol / l) for 15 hours. The TiO ₂ electrode on which the dye was dyed was immersed in 4-tert-butylpyridine for 15 minutes, washed with ethanol and dried naturally. The thickness of the photosensitive layer thus obtained was 10 μm, and the coating amount of the semiconductor fine particles was 20 g / m ² . The surface resistance of the conductive glass was about 30Ω / □.

(3) Preparation of Photoelectrochemical Cell The color-sensitized TiO ₂ electrode substrate (2 cm × 2 cm) prepared as described above was overlaid with platinum-evaporated glass of the same size. Next, 0.65 mol / l of iodine salt of 1-methyl-3-hexylimidazolium and 0.05 iodine of iodine of 1-methyl-3-hexylimidazolium were used as an electrolyte in an electrolytic solution (3-methoxypropionitrile) using a capillary phenomenon in a gap between both glasses. (Mol / liter added) and introduced into a TiO ₂ electrode to obtain a photoelectrochemical cell. According to this embodiment,
As shown in FIG. 1, conductive glass 1 (a conductive agent layer 2 is provided on glass), TiO ₂ layer 3, dye layer 4,
Electrolyte 5, platinum layer 6 and glass 7 were laminated in this order, and a photoelectrochemical cell sealed with an epoxy sealing agent was produced.

(4) Measurement of Photoelectric Conversion Wavelength and Photoelectric Conversion Efficiency The photoelectric conversion capability of the photoelectric conversion element of the present invention was measured using an IPTER manufactured by Optel.
CE (Incident Photonto Current Conversion Efficienc
y) Measured by a measuring device. Table 2 summarizes the wavelength at which the photochemical cell using each dye exhibits the maximum conversion capability and the photoelectric conversion efficiency of the monochromatic light.

[0155]

[Table 2]

All of the dyes of the present invention have high photoelectric conversion characteristics in the near infrared to infrared region. In particular, it can have a high photoelectric conversion ability even in an infrared region having a wavelength longer than 700 nm.

[0157]

According to the present invention, a dye-sensitized photoelectric conversion material and a photoelectric conversion element having high photoelectric conversion characteristics in the near infrared to infrared region are provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a photoelectrochemical cell prepared in an example.

FIG. 2 is a cross-sectional view showing a basic configuration example of a photoelectrochemical cell.

FIG. 3 is a cross-sectional view illustrating a basic configuration example of a photoelectrochemical cell.

FIG. 4 is a cross-sectional view showing an example of a module configuration of a substrate integrated type.

[Description of Signs] 1 conductive glass 2 conductive agent layer 3 TiO ₂ layer 4 dye layer 5 electrolyte 6 platinum layer 7 glass 8 metal layer 9 metal lead 10 dye adsorption TiO ₂ layer 11 charge transfer layer 12 transparent conductive layer 13 transparent Substrate 14 Undercoat layer 15 Support substrate 16 Solid charge transfer layer 17 Anti-reflection layer

Claims (8)

[Claims] Claims: 1. A dye represented by the following general formula (I):
Characterized by containing semiconductor particles sensitized by heat
Conversion material. Embedded imageIn the general formula (I), R₁Is oxygen, sulfur, selenium, tellurium, =
NR₉, = CR_TenR₁₁ R represents any of₉Is hydrogen,
Represents an alkyl group or an aryl group;_Ten, R₁₁Is German
Stand for a substituent. R_Ten, R₁₁Are connected to each other to form a ring
May be implemented. R_TwoIs O^-, S^-, Se^-, Te^-, -NR
₁₂ ^-And R₁₂Represents hydrogen, an alkyl group, or an aryl group.
You. R_Three~ R₈Each independently represents hydrogen or a substituent
And m represents 0 or 1. P₁, P_TwoAre independently
Represents a cycloalkene ring group or a heterocyclic group. W₁Is
If counter ions are needed to neutralize the load
Represent. 2. The dye represented by the general formula (I)
The photoelectric conversion according to claim 1, which is represented by I).
Replacement material. Embedded imageIn the general formula (II), R₁, R_Two, W₁Is synonymous with general formula (I)
is there. R₁₃, R₁₄Are each independently hydrogen, an alkyl group,
Represents an alkenyl group or an aryl group;_{twenty three}~ R₂₈ Each
Independently of hydrogen, alkyl, alkenyl, cycloal
Represents a kill group, an aryl group, or a heterocyclic group. Y₁, Y_TwoHaso
Independently oxygen, sulfur, selenium, tellurium, -CR₁₇R
₁₈-, -NR₁₉-Represents R₁₇, R₁₈, R₁₉Are each
Independently hydrogen, alkyl group, alkenyl group, aryl group
Represent. R_Fifteen, R₁₆Each independently represents a substituent, a,
b represents the integer of 0-4 each independently. a is 2 or more
When R_FifteenMay be the same or different,
A ring may be formed. When b is 2 or more, R₁₆Is the same
And may be mutually connected to form a ring. 3. A dye represented by formula (I) or (II), R ₂ is O ^- expressed in, and characterized in that R ₁ represents oxygen or = CR ₁₀ R ₁₁ The photoelectric conversion material according to claim 1. 4. In the general formula (II), Y ₁ and Y ₂ are each —CR ₁₇ R
_The photoelectric conversion material according to claim 2, wherein the photoelectric conversion material is represented by ₁₈ −. 5. The photoelectric conversion material according to claim 1, wherein the dye represented by formula (I) or (II) has at least one acidic group. 6. The semiconductor fine particles sensitized by a dye are titanium oxide fine particles.
The photoelectric conversion material according to any one of the above. 7. A photoelectric conversion element comprising a conductive support coated with the photoelectric conversion material according to claim 1, a charge transfer layer, and a counter electrode. 8. A compound represented by the following general formula (III)
Characteristic polymethine dye. [Formula 3] 1In the general formula (III), R_Two, R₁₃, R₁₄, R_{twenty three}~ R₂₈,
Y₁, Y_Two, A, b, m, W₁Is synonymous with general formula (II)
You. R_{twenty one}Is oxygen, sulfur, selenium, tellurium, = NR₉, =
CR₃₁R₃₂R represents any of₉Is hydrogen, alkyl
Group, aryl group, R₃₁ , R₃₂Are each independently cyano
Group, alkoxycarbonyl group, carboxyl group, acyl
Group, acyloxy group, thioacylthio group, alkyl sulf
Honyl group, arylsulfonyl group, sulfonic acid group, sulfonate group
Honamido group, carbamoyl group, amino group, acylamido
Group, alkyl group, alkenyl group, aryl group, alcohol
Xy group, alkylthio group, aryloxy group, hetero ring
Group, phosphonyl group, phosphoryl group, hydroxamic acid group
Represent. R₃₁, R₃₂May be linked to each other to form a ring
No. R₂₉, R₃₀Are each independently a cyano group, an alkoxy
Carbonyl, carboxyl, acyl, acyloxy
Si group, alkylsulfonyl group, arylsulfonyl group,
Sulfonic acid group, sulfonamide group, carbamoyl group,
Amino group, acylamino group, alkyl group, alkenyl group,
Aryl group, alkoxy group, alkylthio group, aryl
Oxy group, heterocyclic group, phosphonyl group, phosphoryl group,
Hydroxamic acid groups, hydroxyl groups, alkynyl groups,
Represents a cycloalkyl group or a halogen atom. if a is 2 or more
Come, R₂₉May be the same or different, and
May be formed. When b is 2 or more, R₃₀Is the same
They may be different and may be connected to each other to form a ring.