JP5756772B2 - Photoelectric conversion element and photoelectrochemical cell - Google Patents

Description

  The present invention relates to a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability.

  Photoelectric conversion elements are used in various optical sensors, copying machines, photoelectrochemical cells (for example, solar cells), and the like. Various types of photoelectric conversion elements have been put to practical use, such as those using metals, semiconductors, organic pigments and dyes, or combinations thereof. Above all, a solar cell using non-depleting solar energy does not require fuel, and its full-scale practical use is expected greatly as it uses inexhaustible clean energy. Among these, silicon solar cells have been researched and developed for a long time. It is spreading due to the policy considerations of each country. However, silicon is an inorganic material, and its throughput and molecular modification are naturally limited.

  Therefore, research on dye-sensitized solar cells has been vigorously conducted. In particular, Graetzel et al. Of Lausanne University of Technology in Switzerland developed a dye-sensitized solar cell in which a dye composed of a ruthenium complex was fixed on the surface of a porous titanium oxide thin film, and realized conversion efficiency comparable to amorphous silicon. As a result, dye-sensitized solar cells have attracted a great deal of attention from researchers around the world.

Patent Document 1 describes a dye-sensitized photoelectric conversion element using semiconductor fine particles sensitized with a ruthenium complex dye by applying this technique. In addition, a photoelectric conversion element using an inexpensive organic dye as a sensitizer has been reported.
Patent Document 2 proposes a photosensitized solar cell that effectively absorbs sunlight and improves photoelectric conversion efficiency by using a dye having a specific structure.
Also proposed is a photovoltaic cell in which photoelectric conversion efficiency is improved by incorporating a dopant into at least one of the core and shell of multi-layered titanium oxide fine particles having a core as a central part and a shell as an outer shell. (For example, refer to Patent Document 3).
When the present inventors produced and evaluated the photoelectric conversion element using the pigment | dye and semiconductor fine particle which were described in these patent documents, it turned out that durability may not be enough. The photoelectric conversion elements described in these patent documents are not sufficient because the photoelectric conversion elements are required to have high initial conversion efficiency, low conversion efficiency after use, and excellent durability.

US Pat. No. 5,463,057 JP 2009-200028 A JP 2004-10403 A

  An object of the present invention is to provide a photoelectric conversion element and a photoelectrochemical cell having high photoelectric conversion efficiency and excellent durability.

The inventors of the present invention made photoelectric conversion elements using various semiconductor fine particles and dyes, and intensively studied the photoelectric conversion efficiency and durability. As a result, the durability cannot be improved by simply mixing different semiconductor fine particles, and the durability can be improved simply by using tin oxide coated with aluminum oxide or magnesium oxide as the semiconductor fine particles. I found it difficult to do.
Therefore, the present inventors conducted extensive studies on semiconductor fine particles and pigments. As a result, the photoelectric conversion element and the photoelectrochemical cell using the metal complex dye in which the semiconductor fine particles have two or more kinds of metals or metal compounds and the ligand has a specific substituent are the initial photoelectric It was found that not only conversion efficiency but also durability was excellent.
The present invention has been made based on these findings.

According to the present invention, the following means are provided.
<1> A photoelectric conversion element comprising a conductive support, a photoreceptor layer composed of a semiconductor fine particle layer containing a dye, a charge transfer layer, and a counter electrode, wherein the semiconductor fine particles are two or more kinds of metals. or locally has become in a metal compound, Ri compound der which the dye is represented by the following general formula (1),
The semiconductor fine particles are
A metal chalcogenide or metal carbonate selected from the group consisting of aluminum oxide, magnesium oxide, calcium carbonate, titanium oxide and titanium oxide / magnesium oxide, having as its core a metal chalcogenide selected from the group consisting of titanium oxide and tin oxide Semiconductor fine particles having a salt as a shell part, or
Semiconductor fine particles obtained by doping a metal chalcogenide selected from the group consisting of titanium oxide and tin oxide with at least one metal atom selected from the group consisting of Nb, V and Ta,
Der Ru, photoelectric conversion element.

Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · (CI) _m4 General formula (1)

[Mz represents a Ru atom, LL ¹ is a bidentate ligand represented by the following general formula (2), and LL ² is a bidentate ligand represented by the following general formula (3). is there.
X represents a Lee Sochioshianeto group.
CI represents a counter ion that neutralizes the charge of the compound represented by the general formula (1).
m1 represents an integer of 1 or 2 , and when m1 is 2, LL ¹ may be the same or different. m2 is to table an integer of 0 or 1. m3 is to Table 2. m4 represents an integer of 0 to 3, and when m4 is 2 or more, CIs may be the same or different.

In the general formula (2), R ¹⁰¹ and R ¹⁰² represent, respectively it mosquito carboxyl group. R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, and R ¹⁰⁵ and R ¹⁰⁶ each independently represent a group consisting of at least one selected from the group consisting of an alkyl group, an aryl group, and a heterocyclic group.
L ¹ and L ² each independently represents a conjugated chain composed of an ethenylene group and / or an ethynylene group.
a1 and a2 to display the 0 or 1 each independently represents an integer. b1 and b2 represent it respectively 0. d1 and d2 each independently represent an integer of 0 or 1 . d3 represents 1 .

In the general formula (3), Za, Zb and Zc each represent a nonmetallic atom group capable of forming a pyridine ring, and c represents 0. However, when a1 and a2 are each 0 in the general formula (2), each of two pyridine rings formed by Za and Zb has a carboxyl group as a substituent. ]
<2> The photoelectric conversion element according to <1>, wherein the semiconductor fine particles have a particle diameter of 1 to 1000 nm.
<3> The photoelectric conversion element according to <1> or <2>, wherein the semiconductor fine particles include an additive made of a conductive material.
<4> The photoelectric conversion element according to <3>, wherein the conductive material is graphene.
<5> The photoelectric conversion element according to any one of <1> to <4>, wherein LL ¹ is represented by the general formula (4-3) in the general formula (1).

[R ^{101 to} R ¹⁰⁴ , a 1, a 2, b 1, b 2, and d 3 have the same meaning as in general formula (2) . R ¹²⁷ and R ¹²⁸ each independently represents an alkyl group or an alkynyl group . ]
< 6 > A photoelectrochemical cell comprising the photoelectric conversion element according to any one of <1> to < 5 >.

  According to the present invention, it is possible to provide a photoelectric conversion element and a photoelectrochemical cell having high conversion efficiency and excellent durability.

It is sectional drawing shown typically about one embodiment of the photoelectric conversion element of this invention.

  As a result of intensive studies, the inventors have made a photoelectric conversion comprising a conductive support, a photosensitive layer composed of a semiconductor fine particle layer containing a dye of a specific compound, a charge transfer layer, and a counter electrode. It was discovered that a photoelectric conversion element and a photoelectrochemical cell, each of which is an element and the semiconductor fine particles locally have two or more kinds of metals or metal compounds, have high conversion efficiency and excellent durability. . The present invention has been made based on these findings.

  A preferred embodiment of the photoelectric conversion element of the present invention will be described with reference to the schematic cross-sectional view of FIG.

As shown in FIG. 1, the photoelectric conversion element 10 includes a conductive support 1, a photosensitive layer 2, a charge transfer layer 3, and a counter electrode 4 arranged in that order on the conductive support 1. The conductive support 1 and the photoreceptor layer 2 constitute a light receiving electrode 5.
The photoreceptor layer 2 has semiconductor fine particles 22 and a sensitizing dye (hereinafter also simply referred to as a dye) 21. At least a part of the sensitizing dye 21 is adsorbed on the semiconductor fine particles 22 (the sensitizing dye 21 is in an adsorption equilibrium state and may partially exist in the charge transfer layer 3). The charge transfer body layer 3 functions as, for example, a hole transport layer that transports holes. The conductive support 1 on which the photoreceptor layer 2 is formed functions as a working electrode in the photoelectric conversion element 10. The photoelectric conversion element 10 can be operated as the photoelectrochemical cell 100 by causing the external circuit 6 to work.

  The light receiving electrode 5 is an electrode composed of a conductive support 1 and a photosensitive layer 2 (semiconductor film) of semiconductor fine particles 22 adsorbed by a sensitizing dye 21 coated on the conductive support 1. Light incident on the photoreceptor layer 2 (semiconductor film) excites the dye. The excited dye has high energy electrons. Therefore, the electrons are transferred from the sensitizing dye 21 to the conduction band of the semiconductor fine particles 22 and reach the conductive support 1 by diffusion. At this time, the molecule of the sensitizing dye 21 is an oxidant. The electrons on the electrode return to the oxidant while working in the external circuit 6, thereby acting as the photoelectrochemical cell 100. At this time, the light receiving electrode 5 functions as a negative electrode of the battery.

  The photoreceptor layer 2 is composed of a porous semiconductor layer composed of a layer of semiconductor fine particles 22 to which a dye described later is adsorbed. This dye may be partially dissociated in the electrolyte. The photoreceptor layer 2 is designed according to the purpose and has a multilayer structure.

  As described above, since the photosensitive layer 2 includes the semiconductor fine particles 22 on which a specific dye is adsorbed, the light receiving sensitivity is high, and when used as the photoelectrochemical cell 100, high photoelectric conversion efficiency can be obtained. Furthermore, it has high durability.

(A) Dye In the photoreceptor layer 2, the porous semiconductor layer is sensitized with at least one dye 21 represented by the following general formula (1).

Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · CI General formula (1)

(A1) Metal atom Mz
Mz is to table the Ru atom.

(A2) Ligand LL ¹
The ligand LL ¹ is a bidentate ligand represented by the general formula (2).
M1 representing the number of ligands LL ¹ is an integer of 1 or 2 . When m1 is 2 , the ligands LL ¹ may be the same or different. m1 is preferably 1.

In the general formula (2), R ¹⁰¹ and R ¹⁰² represent, respectively it mosquito carboxyl group. R ¹⁰¹ and R ¹⁰² may be substituted on any carbon atom on the pyridine ring.

a1 and a2 each independently represent an integer of 0 or 1 . the sum of a 1 and a2 is preferably an integer of 0 to 2.

In the general formula (2), R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, preferably an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, such as methyl, ethyl, isopropyl, t-butyl, pentyl. , Heptyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl, 1-carboxymethyl, etc.), an alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, such as vinyl, allyl, oleyl, etc.), an alkynyl group ( Preferably an alkynyl group having 2 to 20 carbon atoms such as ethynyl, butadiynyl, phenylethynyl, etc., a cycloalkyl group (preferably a cycloalkyl group having 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, 4 -Methylcyclohexyl, etc.), an aryl group (preferably an ant having 6 to 26 carbon atoms) Group such as phenyl, 1-naphthyl, 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl and the like, a heterocyclic group (preferably a heterocyclic group having 2 to 20 carbon atoms, such as 2-pyridyl, 4-pyridyl, 2-imidazolyl, 2-benzimidazolyl, 2-thiazolyl, 2-oxazolyl, etc.), an alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, such as methoxy, ethoxy, isopropyloxy, benzyloxy, etc.) An aryloxy group (preferably an aryloxy group having 6 to 26 carbon atoms, such as phenoxy, 1-naphthyloxy, 3-methylphenoxy, 4-methoxyphenoxy, etc.), an alkoxycarbonyl group (preferably having 2 to 2 carbon atoms) 20 alkoxycarbonyl groups such as ethoxycarbonyl, 2-ethylhexyloxycarbonyl, etc.), Mino group (preferably an amino group having 0 to 20 carbon atoms, such as amino, N, N-dimethylamino, N, N-diethylamino, N-ethylamino, anilino, etc.), sulfonamide group (preferably the number of carbon atoms 0-20 sulfonamide groups, such as N, N-dimethylsulfonamide, N-phenylsulfonamide, etc.), acyloxy groups (preferably acyloxy groups having 1-20 carbon atoms, such as acetyloxy, benzoyloxy, etc.) A carbamoyl group (preferably a carbamoyl group having 1 to 20 carbon atoms such as N, N-dimethylcarbamoyl, N-phenylcarbamoyl, etc.), an acylamino group (preferably an acylamino group having 1 to 20 carbon atoms such as acetyl Amino, benzoylamino, etc.), cyano group, or halogen atom (for example, fluorine atom, chlorine atom, bromine atom, And more preferably an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an amino group, an acylamino group, a cyano group, or a halogen atom, An alkyl group, an alkenyl group, a heterocyclic group, an alkoxy group, an alkoxycarbonyl group, an amino group, an acylamino group, or a cyano group is preferable.

b1 and b2 are to table it respectively 0.

In the general formula (2), R ¹⁰⁵ and R ¹⁰⁶ each independently represent a group consisting of at least one selected from the group consisting of an alkyl group, an aryl group, and a heterocyclic group. R ¹⁰⁵ and R ¹⁰⁶ are each independently an aromatic group (preferably an aromatic group having 6 to 30 carbon atoms, such as phenyl, substituted phenyl, naphthyl, substituted naphthyl, etc.) or a heterocyclic group (preferably a carbon atom A heterocyclic group having a number of 1 to 30, for example, 2-thienyl group, 2-pyrrolyl group, 2-imidazolyl group, 1-imidazolyl group, 4-pyridyl group, 3-indolyl group) is preferable, and 1 to 3 electrons A heterocyclic group having a donor group is more preferred, and a thienyl group is more preferred. Electric child Azukamoto alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group, an acylamino group (preferred examples above if the same R ¹⁰¹ and R ¹⁰²⁾ are or hydroxyl groups preferably An alkyl group, an alkoxy group, an amino group or a hydroxyl group is more preferable, and an alkyl group is particularly preferable. R ¹⁰⁵ and R ¹⁰⁶ may be the same or different, but are preferably the same.

In the general formula (2), L ¹ and L ² each independently represent a conjugated chain composed of an ethenylene group and / or an ethynylene group. When the ethenylene group has a substituent, examples of the substituent include those shown as specific examples of the substituent for R ¹⁰³ and R ¹⁰⁴ . The substituent is preferably an alkyl group, and more preferably methyl. L ¹ and L ² are each independently preferably a conjugated chain having 2 to 6 carbon atoms, more preferably ethenylene, butadienylene, ethynylene, butadienylene, methylethenylene or dimethylethenylene, particularly ethenylene or butadienylene. Preferably, ethenylene is most preferred. L ¹ and L ² may be the same or different, but are preferably the same. When the conjugated chain includes a carbon-carbon double bond, each double bond may be a trans isomer, a cis isomer, or a mixture thereof.

d1 and d2 each independently represent an integer of 0 or 1 . If d1 and d2 is 0, R ¹⁰⁵ and R ¹⁰⁶ are directly bonded to the benzene ring. When d1 and d2 are 1 , R ¹⁰⁵ and R ¹⁰⁶ are bonded to the benzene ring via L ¹ or L ² .

d3 represents 1 .

When the ligand LL ¹ contains an alkyl group, an alkenyl group or the like, these may be linear or branched, and may be substituted or unsubstituted. Further, when the ligand LL ¹ contains an aromatic group such as an aryl group, a heterocyclic group or the like, these may be monocyclic or condensed, and may be substituted or unsubstituted. Examples of the substituent include those shown as specific examples of the substituent for R ¹⁰³ and R ¹⁰⁴ .

The ligand LL ¹ in the general formula (1) is preferably represented by the following general formula (4-1), (4-2) or (4-3).

In the general formulas (4-1) to (4-3), R ^{101 to} R ¹⁰⁴ , a1, a2, b1, b2, and d3 have the same meanings as those in the general formula (2), and preferred ranges are also the same. .

In the general formula (4-2), R ¹⁰⁷ represents an acidic group, preferably a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group, more preferably a carboxyl group or a phosphoryl group. A carboxyl group is more preferable.

In general formula (4-2), a3 represents the integer of 0-3, Preferably the integer of 0-2 is represented. When d3 is 0, a3 is preferably 1 or 2, and when d3 is 1, a3 is preferably 0 or 1. a3 is the R ¹⁰⁷ when two or more may be the same or different.

In the general formula (4-2), R ¹⁰⁸ represents a substituent, preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group or an acylamino group (above preferred examples are R ¹⁰³ and R ¹⁰⁴ in the general formula (2), and more preferably an alkyl group, an alkoxy group, an amino group, or an acylamino group.

In general formula (4-2), b3 represents the integer of 0-3, Preferably the integer of 0-2 is represented. When b3 is 2 or more, R ¹⁰⁸ may be the same or different.

In General Formulas (4-1) and (4-2), R ^{121 to} R ¹²⁴ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an aryl group. Preferred examples of R ^{121 to} R ¹²⁴ are the same as the preferred examples of R ¹⁰³ and R ¹⁰⁴ in formula (2). R ^{121 to} R ¹²⁴ are more preferably an alkyl group or an aryl group, and still more preferably an alkyl group. When R ^{121 to} R ¹²⁴ are alkyl groups, they may further have a substituent, and the substituent is preferably an alkoxy group, a cyano group, an alkoxycarbonyl group or a carbonamido group, particularly preferably an alkoxy group.
R ¹²¹ and R ^{122 and} R ¹²³ and R ¹²⁴ may be connected to each other to form a ring. As the ring to be formed, a pyrrolidine ring, a piperidine ring, a piperazine ring, a morpholine ring or the like is preferable.

In the general formulas (4-1) to (4-3), R ¹²⁵ , R ¹²⁶ , R ¹²⁷ and R ¹²⁸ each independently represent a substituent, preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, An alkoxy group, an aryloxy group, an amino group, an acylamino group (preferred examples are the same as those for R ¹⁰³ and R ¹⁰⁴ in the general formula (2)) or a hydroxyl group, more preferably an alkyl group, An alkenyl group, an alkynyl group, an alkoxy group, an amino group or an acylamino group, particularly preferably an alkyl group or an alkynyl group.

In General Formulas (4-1) and (4-2), d4 and d5 each independently represents an integer of 0 to 4. When d4 is 1 or more, R ¹²⁵ may be linked to one or both of R ¹²¹ and R ¹²² to form a ring. The ring formed is preferably a piperidine ring or a pyrrolidine ring. When d4 is 2 or more, R ¹²⁵ may be the same or different, and may be linked to each other to form a ring. When d5 is 1 or more, R ¹²⁶ may be linked to one or both of R ¹²³ and R ¹²⁴ to form a ring. The ring formed is preferably a piperidine ring or a pyrrolidine ring. When d5 is 2 or more, R ¹²⁶ may be the same or different and may be linked to each other to form a ring.

(A3) Ligand LL ²
Ligand LL ² are Oh Ru in bidentate ligand represented by the general formula (3).
M2 representing the number of ligands LL ² is an integer of 0 or 1 , and 1 is more preferable .
In the present invention, the ligand LL ² preferably has an acidic group such as a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group, or a phosphonyl group.

In the general formula (3), Za, Zb and Zc each represent a nonmetallic atom group capable of forming a pyridine ring . The formed pyridine ring may be substituted or unsubstituted, and may be monocyclic or condensed. Examples of the substituent include the substituent W described later.

The pyridine ring formed by Za, Zb and Zc may have a hydrogen atom or a halogen atom. Moreover, when a1 and a2 are each 0 in General formula (2), each of the two pyridine rings formed by Za and Zb has a carboxyl group as a substituent.

In general formula (3), c represents 0 .

The ligand LL ² is preferably represented by any one of the following general formulas (5-1) to (5- 4 ), and the general formula (5-1), (5-2), or (5-4) ), More preferably represented by formula (5-1) or (5-2), and most preferably represented by formula (5-1). .

Although the general formula (5-1) ~ (5- 4) R 151 ~ R 154 and R ¹⁵⁹ ~ R ¹⁶² in are depicted as substituted on convenience one illustrated ring, the ring It may be above or substituted with a different ring from that shown.

In the general formula (5-1) ~ (5- 4) , R 151 ~R 154 each independently represent an acidic group. R ^{151 to} R ¹⁵⁴ are, for example, a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group (preferably a hydroxamic acid group having 1 to 20 carbon atoms, such as —CONHOH, —CONCH ₃ OH, etc.), a phosphoryl group ( For example, -OP (O) (OH) ₂ etc.) or a phosphonyl group (for example, -P (O) (OH) ₂ etc.) is represented. R ^{151 to} R ¹⁵⁴ are preferably a carboxyl group, a phosphoryl group, or a phosphonyl group, more preferably a carboxyl group or a phosphonyl group, and even more preferably a carboxyl group.

In the general formula (5-1) ~ (5- 4) , R 159 ~R 162 independently represents a substituent, preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a heterocyclic group, an alkoxy group , An aryloxy group, an alkoxycarbonyl group, an amino group, an acyl group, a sulfonamide group, an acyloxy group, a carbamoyl group, an acylamino group, a cyano group, or a halogen atom (above preferred examples are R ¹⁰³ and R ¹⁰⁴ in the general formula (2)) More preferably an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an alkoxycarbonyl group, an amino group, an acylamino group or a halogen atom, particularly preferably an alkyl group or an alkenyl group. , An alkoxy group, an alkoxycarbonyl group, an amino group, or an acylamino group.

In the general formula (5-1) ~ (5- 4) , R 151 ~ R 154 and R ¹⁵⁹ ~ R ¹⁶² may be bonded to any position on the ring.

In the general formula (5-1) ~ (5- 4) , e1~e 4 each independently represents an integer of 0 to 4, preferably an integer of 1-2. e 9~e1 2 each independently represents an integer of 0-6. E9～e 12 is is preferably each independently an integer of 0-3.

When E1～e 4 is 2 or more, may be R ¹⁵¹ to R ¹⁵⁴ may be the same or different, respectively, may form a ring. When E9～e 12 is 2 or more, may be R ¹⁵⁹ to R ¹⁶² may be the same or different, respectively, may form a ring.

When the ligand LL ² contains an alkyl group, an alkenyl group or the like, they may be linear or branched and may be unsubstituted substituted. Further, when the ligand LL ² contains an aromatic group such as an aryl group, a heterocyclic group or the like, these may be monocyclic or condensed, and may be substituted or unsubstituted.

(A4) Ligand X
In the general formula (1), the ligand X represents an isothiocyanate group . To Table 2 is m3 which represents the number of ligands X.

(A5) Counter ion CI
CI in the general formula (1) represents a counter ion when a counter ion is necessary to neutralize the charge. In general, whether a dye is a cation or an anion, or has a net ionic charge, depends on the metal, ligand and substituent in the dye.

  The dye of the general formula (1) may be dissociated and have a negative charge because the substituent has a dissociable group. In this case, the entire charge of the dye of the general formula (1) is electrically neutralized by the counter ion CI. M4 which is the number of CI is an integer of 0-3.

  When the counter ion CI is a positive counter ion, examples of the counter ion CI include inorganic or organic ammonium ions (for example, tetraalkylammonium ions, pyridinium ions, etc.), alkali metal ions, and protons.

  When the counter ion CI is a negative counter ion, the counter ion CI may be an inorganic anion or an organic anion. For example, halogen anions (eg, fluoride ions, chloride ions, bromide ions, iodide ions, etc.), substituted aryl sulfonate ions (eg, p-toluene sulfonate ions, p-chlorobenzene sulfonate ions, etc.), aryl disulfones Acid ions (for example, 1,3-benzenedisulfonate ion, 1,5-naphthalenedisulfonate ion, 2,6-naphthalenedisulfonate ion, etc.), alkyl sulfate ions (for example, methyl sulfate ion), sulfate ions, thiocyanate ions Perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, picrate ion, acetate ion, trifluoromethanesulfonate ion and the like. Furthermore, an ionic polymer or another dye having a charge opposite to that of the dye may be used as the charge balance counter ion, and a metal complex ion (for example, bisbenzene-1,2-dithiolatonickel (III)) can also be used. is there.

(A6) Adsorbing group (bonding group)
The dye having the structure represented by the general formula (1) has one or more suitable acidic groups (bonding groups) to the surface of the semiconductor fine particles. It is more preferable to have 1 to 6 of these groups in the dye, and it is particularly preferable to have 1 to 4 of these groups. Carboxyl group, sulfonic acid group, hydroxyl group, hydroxamic acid group (for example, -CONHOH), phosphoryl group (for example, -OP (O) (OH) ₂ ), phosphonyl group (for example, -P (O) (OH) ₂ ) It is preferable that the dye has an acidic group (substituent having a dissociable proton). Especially, it is preferable to have a carboxyl group (COOH group) on a ligand. In the present specification, an acidic group refers to a substituent that releases a proton. In addition, when “having a specific functional substituent” such as “having an acidic group”, the functional substituent is directly bonded to the mother nucleus within a range not impairing the effects of the present invention. In addition, it is meant to include those linked (linked) via a predetermined linking group.

The substituent in this specification can represent the substituent W shown below, for example except what was described especially.
・ Halogen atoms (for example, fluorine atom, chlorine atom, bromine atom, iodine atom),
-Alkyl group [Represents a linear, branched, or cyclic substituted or unsubstituted alkyl group. They are alkyl groups (preferably alkyl groups having 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, eicosyl, 2-chloroethyl, 2-cyanoethyl, 2-ethylhexyl) A cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, such as cyclohexyl, cyclopentyl, 4-n-dodecylcyclohexyl), a bicycloalkyl group (preferably having 5 to 30 carbon atoms). A substituted or unsubstituted bicycloalkyl group, that is, a monovalent group obtained by removing one hydrogen atom from a bicycloalkane having 5 to 30 carbon atoms, for example, bicyclo [1,2,2] heptan-2-yl, bicyclo [2,2,2] octan-3-yl), and tricyclo structures having more ring structures are also included. An alkyl group (for example, an alkyl group of an alkylthio group) in the substituents described below also represents such an alkyl group. ],
-Alkenyl group [Represents a linear, branched, or cyclic substituted or unsubstituted alkenyl group. They are alkenyl groups (preferably substituted or unsubstituted alkenyl groups having 2 to 30 carbon atoms, such as vinyl, allyl, prenyl, geranyl, oleyl), cycloalkenyl groups (preferably substituted or substituted groups having 3 to 30 carbon atoms). An unsubstituted cycloalkenyl group, that is, a monovalent group obtained by removing one hydrogen atom of a cycloalkene having 3 to 30 carbon atoms (for example, 2-cyclopenten-1-yl, 2-cyclohexen-1-yl), Bicycloalkenyl group (a substituted or unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, that is, a monovalent group obtained by removing one hydrogen atom of a bicycloalkene having one double bond. For example, bicyclo [2,2,1] hept-2-en-1-yl, bicyclo [2,2,2] oct-2-en-4-yl) It is intended to embrace. ],
An alkynyl group (preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, such as ethynyl, propargyl, trimethylsilylethynyl group, aryl group (preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, Such as phenyl, p-tolyl, naphthyl, m-chlorophenyl, o-hexadecanoylaminophenyl),
Aromatic groups (for example, benzene ring, furan ring, pyrrole ring, pyridine ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyrazole ring, isoxazole ring, isothiazole ring, pyrimidine ring, pyrazine ring or these A ring fused with
A heterocyclic group (preferably a monovalent group obtained by removing one hydrogen atom from a 5- or 6-membered substituted or unsubstituted aromatic or non-aromatic heterocyclic compound, more preferably a carbon number of 3 To 30- or 5-membered aromatic heterocyclic group such as 2-furyl, 2-thienyl, 2-pyrimidinyl, 2-benzothiazolyl),
A cyano group,
・ Hydroxyl group,
・ Nitro group,
・ Carboxyl group,
An alkoxy group (preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, such as methoxy, ethoxy, isopropoxy, t-butoxy, n-octyloxy, 2-methoxyethoxy),
Aryloxy group (preferably a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, such as phenoxy, 2-methylphenoxy, 4-t-butylphenoxy, 3-nitrophenoxy, 2-tetradecanoylamino Phenoxy),
A silyloxy group (preferably a silyloxy group having 3 to 20 carbon atoms, such as trimethylsilyloxy, t-butyldimethylsilyloxy),
A heterocyclic oxy group (preferably a substituted or unsubstituted heterocyclic oxy group having 2 to 30 carbon atoms, 1-phenyltetrazol-5-oxy, 2-tetrahydropyranyloxy),
An acyloxy group (preferably a formyloxy group, a substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms, such as formyloxy, acetyloxy, Pivaloyloxy, stearoyloxy, benzoyloxy, p-methoxyphenylcarbonyloxy),
A carbamoyloxy group (preferably a substituted or unsubstituted carbamoyloxy group having 1 to 30 carbon atoms, such as N, N-dimethylcarbamoyloxy, N, N-diethylcarbamoyloxy, morpholinocarbonyloxy, N, N-di -n-octylaminocarbonyloxy, Nn-octylcarbamoyloxy),
An alkoxycarbonyloxy group (preferably a substituted or unsubstituted alkoxycarbonyloxy group having 2 to 30 carbon atoms, such as methoxycarbonyloxy, ethoxycarbonyloxy, t-butoxycarbonyloxy, n-octylcarbonyloxy),
An aryloxycarbonyloxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having 7 to 30 carbon atoms, such as phenoxycarbonyloxy, p-methoxyphenoxycarbonyloxy, pn-hexadecyloxyphenoxycarbonyloxy),
Amino groups (preferably amino groups, substituted or unsubstituted alkylamino groups having 1 to 30 carbon atoms, substituted or unsubstituted anilino groups having 6 to 30 carbon atoms, such as amino, methylamino, dimethylamino, anilino N-methyl-anilino, diphenylamino),
Acylamino group (preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms, substituted or unsubstituted arylcarbonylamino group having 6 to 30 carbon atoms, such as formylamino, acetylamino Pivaloylamino, lauroylamino, benzoylamino, 3,4,5-tri-n-octyloxyphenylcarbonylamino),
Aminocarbonylamino group (preferably substituted or unsubstituted aminocarbonylamino having 1 to 30 carbon atoms, such as carbamoylamino, N, N-dimethylaminocarbonylamino, N, N-diethylaminocarbonylamino, morpholinocarbonylamino) ,
An alkoxycarbonylamino group (preferably a substituted or unsubstituted alkoxycarbonylamino group having 2 to 30 carbon atoms, such as methoxycarbonylamino, ethoxycarbonylamino, t-butoxycarbonylamino, n-octadecyloxycarbonylamino, N-methyl- Methoxycarbonylamino),
An aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms, such as phenoxycarbonylamino, p-chlorophenoxycarbonylamino, mn-octyloxyphenoxycarbonylamino),
A sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, such as sulfamoylamino, N, N-dimethylaminosulfonylamino, Nn-octylaminosulfonylamino) ,
Alkyl and arylsulfonylamino groups (preferably substituted or unsubstituted alkylsulfonylamino having 1 to 30 carbon atoms, substituted or unsubstituted arylsulfonylamino having 6 to 30 carbon atoms, such as methylsulfonylamino, butylsulfonylamino, Phenylsulfonylamino, 2,3,5-trichlorophenylsulfonylamino, p-methylphenylsulfonylamino),
・ Mercapto group,
An alkylthio group (preferably a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, such as methylthio, ethylthio, n-hexadecylthio),
An arylthio group (preferably a substituted or unsubstituted arylthio having 6 to 30 carbon atoms, such as phenylthio, p-chlorophenylthio, m-methoxyphenylthio),
A heterocyclic thio group (preferably a substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms, such as 2-benzothiazolylthio, 1-phenyltetrazol-5-ylthio),
A sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, such as N-ethylsulfamoyl, N- (3-dodecyloxypropyl) sulfamoyl, N, N-dimethylsulfamoyl, N -Acetylsulfamoyl, N-benzoylsulfamoyl, N- (N'-phenylcarbamoyl) sulfamoyl),
・ Sulfo group,
Alkyl and arylsulfinyl groups (preferably substituted or unsubstituted alkylsulfinyl groups having 1 to 30 carbon atoms, substituted or unsubstituted arylsulfinyl groups having 6 to 30 carbon atoms such as methylsulfinyl, ethylsulfinyl, phenylsulfinyl, p -Methylphenylsulfinyl),
Alkyl and arylsulfonyl groups (preferably substituted or unsubstituted alkylsulfonyl groups having 1 to 30 carbon atoms, substituted or unsubstituted arylsulfonyl groups having 6 to 30 carbon atoms such as methylsulfonyl, ethylsulfonyl, phenylsulfonyl, p- Methylphenylsulfonyl),
Acyl group (preferably formyl group, substituted or unsubstituted alkylcarbonyl group having 2 to 30 carbon atoms, substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, substituted or unsubstituted carbon group having 4 to 30 carbon atoms A heterocyclic carbonyl group bonded to a carbonyl group at a carbon atom (eg, acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, pn-octyloxyphenylcarbonyl, 2-pyridylcarbonyl, 2-furylcarbonyl),
An aryloxycarbonyl group (preferably a substituted or unsubstituted aryloxycarbonyl group having 7 to 30 carbon atoms, such as phenoxycarbonyl, o-chlorophenoxycarbonyl, m-nitrophenoxycarbonyl, pt-butylphenoxycarbonyl),
An alkoxycarbonyl group (preferably a substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, n-octadecyloxycarbonyl),
A carbamoyl group (preferably a substituted or unsubstituted carbamoyl having 1 to 30 carbon atoms such as carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N, N-di-n-octylcarbamoyl, N- ( Methylsulfonyl) carbamoyl),
Aryl and heterocyclic azo groups (preferably substituted or unsubstituted arylazo groups having 6 to 30 carbon atoms, substituted or unsubstituted heterocyclic azo groups having 3 to 30 carbon atoms, such as phenylazo, p-chlorophenylazo, 5 -Ethylthio-1,3,4-thiadiazol-2-ylazo),
An imide group (preferably N-succinimide, N-phthalimide),
A phosphino group (preferably a substituted or unsubstituted phosphino group having 2 to 30 carbon atoms, such as dimethylphosphino, diphenylphosphino, methylphenoxyphosphino),
A phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms, such as phosphinyl, dioctyloxyphosphinyl, diethoxyphosphinyl),
A phosphinyloxy group (preferably a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, such as diphenoxyphosphinyloxy, dioctyloxyphosphinyloxy),
A phosphinylamino group (preferably a substituted or unsubstituted phosphinylamino group having 2 to 30 carbon atoms, such as dimethoxyphosphinylamino, dimethylaminophosphinylamino),
A silyl group (preferably a substituted or unsubstituted silyl group having 3 to 30 carbon atoms, such as trimethylsilyl, t-butyldimethylsilyl, phenyldimethylsilyl).
In addition, the substituent may be further substituted. In that case, the above-mentioned substituent can be mentioned as an example of a substituent.

  In the present invention, among the compounds represented by the general formula (1), a compound in which Mz is Ru, m1 is 1, m2 is 1, X is an isothiocyanate group, and m3 is 2. preferable.

  Specific examples of the dye having the structure represented by the general formula (1) used in the present invention are shown below, but the present invention is not limited thereto. In addition, when the pigment | dye in the following specific example contains the ligand which has a proton dissociable group, this ligand may dissociate as needed and may discharge | release a proton.

  The method of synthesizing the dye represented by the general formula (1) can be referred to the method described in Examples below, and can be synthesized by appropriately applying a conventional method based on the method. In addition, J.H. Am. Chem. Soc., 1999, vol. 121, p. 4047, Can. J. Chem., Vol. 75, p. 318 (1997), Inorg. Chem., 1988, vol. 27, p. Reference can be made to documents such as 4007 and the methods cited in the literature, and the dyes and methods described therein are cited herein. Information described in JP 2001-291534 A and WO 2007/091525 can also be referred to, and the dyes and methods described herein are cited in this specification.

  The maximum absorption wavelength of the dye solution represented by the general formula (1) is preferably in the range of 300 to 1000 nm, more preferably in the range of 350 to 950 nm, and particularly preferably in the range of 370 to 900 nm.

  In the present invention, the content of the dye represented by the general formula (1) is not particularly limited, but is preferably 0.001 to 1 mmol, and preferably 0.1 to 0.5 mmol with respect to 1 g of the semiconductor fine particles. It is more preferable that By setting it as the said lower limit or more, the sensitization effect in a semiconductor can fully be acquired, and the reduction of the sensitization effect by desorption of a pigment | dye can be suppressed by setting it as the said upper limit or less. In the present invention, two or more dyes represented by the general formula (1) may be used.

(B) Charge transfer body layer The layer which consists of electrolyte composition is applicable to the charge transfer body layer used for the photoelectric conversion element of this embodiment. As the redox pair, for example, a combination of iodine and iodide (eg, lithium iodide, tetrabutylammonium iodide, tetrapropylammonium iodide, etc.), alkyl viologen (eg, methyl viologen chloride, hexyl viologen bromide, benzyl viologen tetrafluoro) Borate) and its reduced form, a combination of polyhydroxybenzenes (for example, hydroquinone, naphthohydroquinone, etc.) and its oxidized form, a combination of divalent and trivalent iron complexes (for example, red blood salt and yellow blood salt) Etc. Of these, a combination of iodine and iodide is preferred.
The cation of the iodine salt is preferably a 5-membered or 6-membered nitrogen-containing aromatic cation. In particular, when the compound represented by the general formula (1) is not an iodine salt, it is described in WO95 / 18456, JP-A-8-259543, Electrochemistry, Vol. 65, No. 11, page 923 (1997), etc. It is preferable to use iodine salts such as pyridinium salts, imidazolium salts, and triazolium salts.
The electrolyte composition used for the photoelectric conversion element preferably contains iodine together with the heterocyclic quaternary salt compound. The iodine content is preferably 0.1 to 20% by mass, and more preferably 0.5 to 5% by mass with respect to the entire electrolyte composition.

The electrolyte composition may contain a solvent. The content of the solvent in the electrolyte composition is preferably 50% by mass or less, more preferably 30% by mass or less, and particularly preferably 10% by mass or less based on the entire composition.
As the solvent, a solvent having a low viscosity and high ion mobility, a high dielectric constant and capable of increasing the effective carrier concentration, or both is preferable because it can exhibit excellent ion conductivity. Examples of such solvents include carbonate compounds (ethylene carbonate, propylene carbonate, etc.), heterocyclic compounds (3-methyl-2-oxazolidinone, etc.), ether compounds (dioxane, diethyl ether, etc.), chain ethers (ethylene glycol dialkyl ether, Propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, polypropylene glycol dialkyl ether, etc.), alcohols (methanol, ethanol, ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, polyethylene glycol monoalkyl ether, polypropylene glycol monoalkyl ether, etc.), Polyhydric alcohols (ethylene glycol, propylene glycol, polyethylene glycol Polypropylene glycol, glycerin, etc.), nitrile compounds (acetonitrile, glutarodinitrile, methoxyacetonitrile, propionitrile, benzonitrile, biscyanoethyl ether, etc.), esters (carboxylic esters, phosphate esters, phosphonates, etc.), non- Protic polar solvent (dimethyl sulfoxide (DMSO), sulfolane, etc.), water, hydrous electrolyte described in JP-A No. 2002-110262, JP-A No. 2000-36332, JP-A No. 2000-243134, and republication WO / 00 And electrolyte solvents described in Japanese Patent No. -54361. These solvents may be used as a mixture of two or more.

  Further, as the electrolyte solvent, an electrochemically inert salt that is in a liquid state at room temperature and / or has a melting point lower than room temperature may be used. For example, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, etc., nitrogen-containing heterocyclic quaternary salt compounds such as imidazolium salt and pyridinium salt, or tetraalkylammonium Examples include salt.

  A polymer or an oil gelling agent may be added to the electrolyte composition, or it may be gelled (solidified) by a technique such as polymerization of polyfunctional monomers or a crosslinking reaction of the polymer.

  When the electrolyte composition is gelled by adding a polymer, the compounds described in Polymer Electrolyte Reviews-1 and 2 (JR MacCallum and CA Vincent, ELSEVIER APPLIED SCIENCE) are added. be able to. In this case, it is preferable to use polyacrylonitrile or polyvinylidene fluoride.

  In the case where the electrolyte composition is gelled by adding an oil gelling agent, J.I. Chem. Soc. Japan, Ind. Chem. Soc., 1943, p. 46779, J.H. Am. Chem. Soc., 1989, vol. 111, p. 5542, J.A. Chem. Soc., Chem. Commun., 1993, p. 390, Angew. Chem. Int. Ed. Engl., 1996, vol. 35, p. 1949, Chem. Lett., 1996, p. 885, J.H. Chem. Soc., Chem. Commun., 1997, p. The compounds described in 545 and the like can be used, and it is preferable to use a compound having an amide structure.

  When gelling the electrolyte composition by polymerization of polyfunctional monomers, prepare a solution from the polyfunctional monomers, polymerization initiator, electrolyte and solvent, and use methods such as casting, coating, dipping, and impregnation. A method in which a sol-like electrolyte layer is formed on an electrode carrying a dye and then gelled by radical polymerization of a polyfunctional monomer is preferred. The polyfunctional monomers are preferably compounds having two or more ethylenically unsaturated groups, such as divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol Ethylene glycol dimethacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate and the like are preferable.

  The gel electrolyte may be formed by polymerization of a mixture containing a monofunctional monomer in addition to the above polyfunctional monomers. Monofunctional monomers include acrylic acid or α-alkyl acrylic acid (acrylic acid, methacrylic acid, itaconic acid, etc.) or esters or amides thereof (methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n- Butyl acrylate, i-butyl acrylate, t-butyl acrylate, n-pentyl acrylate, 3-pentyl acrylate, t-pentyl acrylate, n-hexyl acrylate, 2,2-dimethylbutyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate 4-methyl-2-propylpentyl acrylate, cetyl acrylate, n-octadecyl acrylate, cyclohexyl acrylate, cyclopentyl acrylate, benzyl acrylate, hydroxyethyl acrylate, 2-hydroxy Cypropyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-methoxyethoxyethyl acrylate, phenoxyethyl acrylate, 3-methoxybutyl acrylate, ethyl carbitol acrylate, 2-methyl-2-nitropropyl acrylate, 2, 2,2-trifluoroethyl acrylate, octafluoropentyl acrylate, heptadecafluorodecyl acrylate, methyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, t-pentyl methacrylate, n-octadecyl methacrylate, benzyl methacrylate , Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-methoxy Ciethoxyethyl methacrylate, dimethylaminoethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, heptadecafluorodecyl methacrylate, ethylene glycol ethyl carbonate methacrylate, 2-isobornyl methacrylate, 2-norbornylmethyl methacrylate, 5-norbornen-2-ylmethyl methacrylate, 3-methyl-2-norbornylmethyl methacrylate, acrylamide, Ni-propylacrylamide, Nn-butylacrylamide, Nt-butylacrylamide, N, N- Dimethylacrylamide, N-methylolacrylamide, diacetoneacrylamide, 2-acrylamido-2-methylpropanesulfonic acid, acrylamidopropyltrimethyl Ruammonium chloride, methacrylamide, N-methylmethacrylamide, N-methylolmethacrylamide, etc.), vinyl esters (vinyl acetate, etc.), maleic acid or fumaric acid or esters derived therefrom (dimethyl maleate, maleic acid) Dibutyl, diethyl fumarate, etc.), sodium salt of p-styrenesulfonic acid, acrylonitrile, methacrylonitrile, dienes (butadiene, cyclopentadiene, isoprene, etc.), aromatic vinyl compounds (styrene, p-chlorostyrene, t-butyl) Styrene, α-methylstyrene, sodium styrenesulfonate, etc.), N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide, vinylsulfonic acid, sodium vinylsulfonate Allylsulfo Sodium acid, sodium methacrylate sulfonate, vinylidene fluoride, vinylidene chloride, vinyl alkyl ethers (methyl vinyl ether), ethylene, propylene, butene, isobutene, N- phenylmaleimide, etc. can be used.

The blending amount of the polyfunctional monomer is preferably 0.5 to 70% by mass and more preferably 1.0 to 50% by mass with respect to the whole monomer. The above-mentioned monomers are the same as those described in Takayuki Otsu and Masaaki Kinoshita “Experimental Methods for Polymer Synthesis” (Chemistry Dojin) and Takayuki Otsu “Lecture Polymerization Reaction Theory 1 Radical Polymerization (I)” (Chemical Doujinshi). Polymerization can be performed by radical polymerization which is a polymer synthesis method. The monomer for gel electrolyte used in the present invention can be radically polymerized by heating, light or electron beam, or electrochemically, and is particularly preferably radically polymerized by heating. In this case, preferably used polymerization initiators are 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis (2-methylpropyl). Pionate), azo initiators such as dimethyl 2,2′-azobisisobutyrate, peroxide initiators such as lauryl peroxide, benzoyl peroxide, and t-butyl peroctoate. The preferable addition amount of a polymerization initiator is 0.01-20 mass% with respect to the monomer total amount, More preferably, it is 0.1-10 mass%.
The weight composition range of the monomer in the gel electrolyte is preferably 0.5 to 70% by mass. More preferably, it is 1.0-50 mass%. When the electrolyte composition is gelled by a polymer crosslinking reaction, it is preferable to add a polymer having a reactive group capable of crosslinking to the composition and a crosslinking agent. Preferred reactive groups are nitrogen-containing heterocycles such as pyridine ring, imidazole ring, thiazole ring, oxazole ring, triazole ring, morpholine ring, piperidine ring, piperazine ring, and the preferred crosslinking agent is a functional group capable of nucleophilic attack by the nitrogen atom. Is a compound (electrophile) having two or more of, for example, a bifunctional or higher functional alkyl halide, halogenated aralkyl, sulfonic acid ester, acid anhydride, acid chloride, isocyanate and the like.

The electrolyte composition, the metal iodide (LiI, NaI, KI, CsI , CaI 2 , etc.), a metal bromide (LiBr, NaBr, KBr, CsBr , CaBr 2 , etc.), quaternary ammonium bromine salt (tetraalkylammonium bromide, Pyridinium bromide, etc.), metal complexes (ferrocyanate-ferricyanate, ferrocene-ferricinium ion, etc.), sulfur compounds (sodium polysulfide, alkylthiol-alkyl disulfides, etc.), viologen dye, hydroquinone-quinone, etc. You can do it. These may be used as a mixture.

  Further, in the present invention, J.P. Am. Ceram. Soc., 1997, vol. 80, no. 12, p. Basic compounds such as t-butylpyridine described in 3157-3171, 2-picoline, and 2,6-lutidine may be added. A preferable concentration range in the case of adding a basic compound is 0.05 to 2M. As the electrolyte, a charge transport layer containing a hole conductor material may be used. As the hole conductor material, a 9,9'-spirobifluorene derivative or the like can be used.

(C) Conductive support As the conductive support, glass or a polymer material having a conductive film layer on the surface, such as a metal having a conductive property as the support itself, can be used. It is preferable that the conductive support is substantially transparent. Substantially transparent means that the light transmittance is 10% or more, preferably 50% or more, particularly preferably 80% or more. As the conductive support, a glass or polymer material coated with a conductive metal oxide can be used. The coating amount of the conductive metal oxide at this time is preferably 0.1 to 100 g per 1 m ² of the support of glass or polymer material. When a transparent conductive support is used, light is preferably incident from the support side. Examples of polymer materials that are preferably used include tetraacetyl cellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC), Examples include polyarylate (PAR), polysulfone (PSF), polyester sulfone (PES), polyetherimide (PEI), cyclic polyolefin, and brominated phenoxy. On the conductive support, the surface may be provided with a light management function. For example, an antireflection film in which high refractive films and low refractive index oxide films described in JP-A-2003-123859 are alternately laminated, The light guide function described in Open 2002-260746 is raised.
In addition to this, a metal support can also be preferably used. Examples thereof include titanium, aluminum, copper, nickel, iron, stainless steel, and copper. These metals may be alloys. More preferably, titanium, aluminum, and copper are preferable, and titanium and aluminum are particularly preferable.

It is preferable that the conductive support has a function of blocking ultraviolet light. For example, a method in which a fluorescent material capable of changing ultraviolet light into visible light is present in the transparent support or on the surface of the transparent support, and a method using an ultraviolet absorber are also included.
A function described in JP-A No. 11-250944 may be further provided on the conductive support.

Preferred conductive films include metals (eg, platinum, gold, silver, copper, aluminum, rhodium, indium, etc.), carbon, or conductive metal oxides (indium-tin composite oxide, tin oxide doped with fluorine, etc.) ).
The thickness of the conductive film layer is preferably 0.01 to 30 μm, more preferably 0.03 to 25 μm, and particularly preferably 0.05 to 20 μm.
The lower the surface resistance of the conductive support, the better. The range of the surface resistance is preferably 50 Ω / cm ² or less, more preferably 10 Ω / cm ² or less. This lower limit is not particularly limited, but is usually about 0.1 Ω / cm ² .

Since the resistance value of the conductive film increases as the cell area increases, a collecting electrode may be disposed. A gas barrier film and / or an ion diffusion prevention film may be disposed between the support and the transparent conductive film. As the gas barrier layer, a resin film or an inorganic film can be used.
Moreover, you may provide a transparent electrode and a porous semiconductor electrode photocatalyst content layer. The transparent conductive layer may have a laminated structure, and as a preferable method, for example, FTO can be laminated on ITO.

(D) Semiconductor fine particles Semiconductor fine particles locally contain two or more kinds of metals or metal compounds. In the present invention, the metal compound represents an inorganic compound containing a metal and one or more atoms other than the metal in the molecule, and examples thereof include metal chalcogenides, metal carbonates, and metal nitrates. In the present invention, the semiconductor fine particles locally having two or more kinds of metals or metal compounds are treated with two or more kinds of metals or metal compounds in advance to thereby obtain two or more kinds of metals or fine particles in the fine particles. A metal compound is present locally. The semiconductor fine particles locally having two or more kinds of metals or metal compounds include those having a core-shell structure formed of two or more kinds of metals or metal compounds as described later, The part and other parts are formed of different metals or metal compounds. Therefore, a simple mixture of two or more kinds of semiconductor fine particles is not included. By using a dye having a specific substituent on the semiconductor fine particles locally having two or more kinds of metals or metal compounds, the dye can be efficiently adsorbed onto the semiconductor fine particles and has high durability. A photoelectric conversion element can be realized.

The semiconductor fine particles preferably contain a metal atom, a metal chalcogenide, a metal carbonate and / or a metal nitrate.
Metal atoms include Ti (titanium), Sn (tin), Au (gold), Ag (silver), Cu (copper), Al (aluminum), Zr (zirconium), Nb (niobium), V (vanadium) and Ta At least one selected from the group consisting of (tantalum) is preferred. More preferred are Ti, Sn, Zr, Nb, V, and Ta, and particularly preferred are Nb, V, and Ta.
Metal chalcogenides are cadmium sulfide, cadmium selenide or Ti (titanium), Sn (tin), Zn (zinc), Mg (magnesium), Al (aluminum), W (tungsten), Zr (zirconium), Hf (hafnium) At least one metal oxide selected from the group consisting of Sr (strontium), In (indium), Ce (cerium), Y (yttrium), La (lanthanum), V (vanadium) and Ta (tantalum). preferable. More preferably, it is at least one metal oxide selected from the group consisting of Ti, Sn, Zn, Mg, Al, and more preferably at least one selected from the group consisting of Ti, Sn, Mg, Al. It is a kind of metal oxide, and particularly preferably at least one kind of metal oxide selected from the group consisting of Ti, Sn, and Al.
The metal carbonate is preferably at least one selected from the group consisting of calcium carbonate, potassium carbonate and barium carbonate. More preferred are calcium carbonate and barium carbonate, and particularly preferred is calcium carbonate.
The metal nitrate is preferably lanthanum nitrate.

The semiconductor fine particles having locally two or more kinds of metals or metal compounds preferably have a core-shell structure, and the core-shell structure allows the metal atom, metal chalcogenide, metal carbonate and / or metal nitrate to be contained. More preferably. In the present specification, the “core-shell structure” refers to a structure having a shell portion so as to cover a core portion serving as a nucleus. It is not necessary for the core part to be entirely covered with the shell part, but preferably 50% or more, more preferably 80% or more, particularly 90% of the surface area of the core part is preferably covered with the shell part. . The semiconductor fine particles having a core-shell structure can exhibit an effect of improving the open circuit voltage by suppressing the electrons injected from the excited dye from returning to I ³⁻ in the electrolytic solution.

The semiconductor fine particles having a core-shell structure can be obtained by adding the semiconductor fine particles to be the core to a solution of the metal atom or metal compound to be the shell and reacting appropriately. One kind or two or more kinds of semiconductor fine particles to be used as the core may be used, and one kind or two or more kinds of metal atoms or metal compounds to be used as the shell may be used.
As the core-shell semiconductor fine particles, for example, the core-shell semiconductor fine particles having titanium oxide as a core and calcium carbonate as a shell can be prepared by the following method, but the method and conditions are limited. There is nothing. First, 12 g (0.2 mol) of acetic acid is added dropwise to 58.6 g (0.2 mol) of tetraisopropyl titanate while stirring with a stirrer. The resulting mixture is stirred for 15 minutes and added to 290 mL of distilled water. After stirring for 1 hour, 4 ml of 65% nitric acid is added and heated to 78 ° C. over 40 minutes, keeping the temperature constant for 75 minutes. Remove the reaction vessel from the heater and add 370 mL of water. The obtained liquid is transferred to a titanium autoclave and heated at 250 ° C. for 12 hours. Thereafter, 2.4 mL of 65% nitric acid is added and stirred with an ultrasonic homogenizer, and then the dispersion is concentrated until the amount of titanium oxide is 13 to 15%. Separate the concentrate by centrifugation, discard the supernatant distilled water, and add the same amount of ethanol as the distilled water. Then, the titanium oxide dispersion liquid of a core is obtained by stirring with an ultrasonic homogenizer. Next, titanium oxide particles as a core are added to a 1 to 3% by mass calcium acetate aqueous solution and stirred for 30 minutes to 3 hours. After stirring, the calcium acetate aqueous solution is removed by centrifugation, washed with distilled water, centrifuged, and then fired at 525 ° C. for 1 hour, whereby the core-shell with titanium oxide as the core and calcium carbonate as the shell Semiconductor fine particles having a structure can be obtained.
It can be determined by observation with a transmission electron microscope (TEM) that the obtained semiconductor fine particles have a core-shell structure. The volume ratio of the core portion to the shell portion is not particularly limited, but the core: shell volume ratio is preferably 50:50 to 98: 2, and more preferably 70:30 to 95: 5. This volume ratio can be obtained by observing with TEM.

In the core-shell structure semiconductor fine particles, the core portion preferably includes a metal atom, a metal chalcogenide, or a metal nitrate. More preferably, the core portion is a metal atom or a metal chalcogenide, and particularly preferably, the core portion is a metal chalcogenide. It is preferred that the shell portion comprises a metal chalcogenide or metal carbonate.
When a metal atom is used as the core portion, at least one metal atom selected from the group consisting of Ti, Nb, Sn, Zn and La is preferred. More preferably, they are Ti, Sn, and Zn. Particularly preferred are Ti and Sn. When metal chalcogenide is used as the core portion, it is preferably at least one metal oxide selected from oxides of Ti, Sn, Zn, Mg and Al. More preferred are an oxide of Ti, an oxide of Sn, and an oxide of Zn. Particularly preferred are an oxide of Ti and an oxide of Sn. When metal nitrate is used as the core portion, lanthanum nitrate is preferred.
When a metal chalcogenide is used as the shell portion, it is preferable to use oxides of Ti, Mg, and Al. When using a metal carbonate as the shell portion, it is preferable to use calcium carbonate.

  With respect to the particle size of the semiconductor fine particles, the average particle size of the primary particles is preferably 1 nm or more and 1000 nm or less, more preferably 2 nm or more and 100 nm or less for the purpose of keeping the viscosity of the semiconductor fine particle dispersion high. Here, the particle size refers to that measured by a laser diffraction type particle size distribution measuring device, for example, a master sizer (trade name) manufactured by MALVERN. Two or more kinds of fine particles having different particle size distributions may be mixed. In this case, the average size of the small particles is preferably 5 nm or less. In addition, for the purpose of scattering incident light and improving the light capture rate, large particles having an average particle size exceeding 50 nm can be added to the ultrafine particles at a low content, or another layer can be applied. In this case, the content of the large particles is preferably 50% or less, more preferably 20% or less of the mass of particles having an average particle size of 50 nm or less. The average particle size of the large particles added and mixed for the above purpose is preferably 100 nm or more, and more preferably 250 nm or more.

As a method for producing the semiconductor fine particles, the gel-sol method described in Sakuo Sakuo's “Science of Sol-Gel Method”, Agne Jofu Co., Ltd. (1998) and the like is preferable. Also preferred is a method of producing an oxide by hydrolyzing a chloride developed by Degussa in an oxyhydrogen salt. When the semiconductor fine particles are titanium oxide, the above sol-gel method, gel-sol method, and high-temperature hydrolysis method in oxyhydrogen salt of chloride are preferred, but Kiyoshi Manabu's “Titanium oxide properties and applied technology” The sulfuric acid method and the chlorine method described in Gihodo Publishing (1997) can also be used. Further, as the sol-gel method, the method described in Journal of American Ceramic Society, Vol. 80, No. 12, 3157-3171 (1997), or the chemistry of Burnside et al. The method described in Materials, Vol. 10, No. 9, pages 2419-2425 is also preferable.
When manufacturing semiconductor fine particles having a core-shell structure, first, as described above, the semiconductor fine particles to be the core portion can be manufactured by the conventional method. For example, when titanium oxide (titania) is used as the core, the production method of titania nanoparticles is preferably a method by flame hydrolysis of titanium tetrachloride, a combustion method of titanium tetrachloride, hydrolysis of a stable chalcogenide complex, orthotitanic acid The semiconductor fine particles that become the core portion are produced by hydrolyzing, dissolving and removing the soluble portions after forming the semiconductor fine particles from the soluble portion and the insoluble portion, and hydrothermal synthesis of an aqueous peroxide solution. Then, by the above-mentioned method, it can obtain by adding the semiconductor fine particle which should be a core in the solution of the metal atom or metal compound which should be a shell, and making it react suitably.
Examples of the crystal structure of titania as a core part include anatase type, brookite type, and rutile type, and anatase type and brookite type are preferable. Titania nanotubes, nanowires, and nanorods may be mixed with titania fine particles.

The semiconductor fine particles locally having two or more kinds of metals or metal compounds used in the present invention are semiconductor fine particles having two or more kinds of metal atoms by doping the semiconductor fine particles with metal atoms. There may be. By doping metal atoms, the flat band potential is positively shifted, and the effect of increasing the charge injection efficiency can increase the short-circuit current.
Examples of the metal atom to be doped include Nb, V, and Ta. More preferably, they are Nb and V. For example, Nb powder and tetrabutyl titanate are added to an aqueous solution containing hydrogen peroxide and ammonia (v / v = 5/1) and stirred. After stirring, excess hydrogen peroxide and ammonia are removed by heating to 80 ° C. The obtained solution is transferred to an autoclave made of Teflon (registered trademark) and stirred at 180 ° C. for 20 hours. The obtained precipitate can be doped with metal atoms by a method of washing with distilled water of pH = 7 and drying at 100 ° C. for 6 hours.

The semiconductor fine particles may contain additives other than metal atoms, metal chalcogenides, metal carbonates and metal nitrates. As an additive, a conductive material is preferable. An example of the conductive material is a coating type conductive material. Examples thereof include carbon materials such as carbon nanotubes, graphene, and graphite, π-conjugated polymers that are conductive polymers, and silver nanowires. These materials can form a thin film exhibiting conductivity by coating, and can be manufactured at low cost. Among these, carbon materials such as graphite, graphene, and carbon nanotube are preferable, and graphene is more preferable. By adding a conductive material to the semiconductor fine particles, the aforementioned dye excited by light irradiation can be held as it is, the reaction of returning the dye to the ground state can be suppressed, and battery performance, particularly photoelectric conversion efficiency can be improved. Can do. More preferred is graphite or graphene having a planar structure. An additive such as a conductive material can be added to the semiconductor fine particles by a method in which the additive is added to the semiconductor fine particle paste and dispersed with an ultrasonic homogenizer. The conductive material preferably has an electric resistance value of 10 ⁷ Ω · cm or less, more preferably 10 ⁵ Ω · cm or less.
In addition to the semiconductor fine particles, additives for improving the necking between the semiconductor fine particles and additives on the surface for preventing reverse electron transfer may be used. Examples of preferred additives include ITO, SnO particles, whiskers, fibrous graphite / carbon nanotubes, zinc oxide necking binders, fibrous materials such as cellulose, metals, organic silicon, dodecylbenzenesulfonic acid, silane compounds, etc. Examples thereof include a mobile binding molecule and a potential gradient dendrimer. For the purpose of removing surface defects on the semiconductor fine particles, the semiconductor fine particles may be subjected to acid-base or redox treatment before dye adsorption. Etching, oxidation treatment, hydrogen peroxide treatment, dehydrogenation treatment, UV-ozone, oxygen plasma, or the like may be used.

As the semiconductor fine particles locally having two or more kinds of metals or metal compounds used in the present invention, a core having a metal chalcogenide or a metal carbonate as a shell portion is used. A semiconductor fine particle having a shell structure and a semiconductor fine particle obtained by doping a metal chalcogenide with a metal atom are preferable, and a metal chalcogenide selected from the group consisting of titanium oxide (TiO ₂ ) and tin oxide (SnO ₂ ) is used as a core. As a portion, selected from the group consisting of aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO), calcium carbonate (CaCO ₃ ), titanium oxide (TiO ₂ ) and titanium oxide / magnesium oxide (TiO ₂ / MgO) Core-shell structure having a metal chalcogenide or metal carbonate as a shell portion Fine particles, and the chalcogenide of a metal selected from the group consisting of titanium oxide and tin oxide, Nb, at least one of the semiconductor fine particles obtained metal atom doped selected from the group consisting of V and Ta are more preferred.

(E) Preparation of Semiconductor Fine Particle Dispersion and Production of Semiconductor Fine Particle Layer A semiconductor fine particle layer can be obtained by applying the semiconductor fine particle dispersion to the conductive support and heating it appropriately. In the semiconductor fine particle dispersion, the solid content other than the semiconductor fine particles is preferably 10% by mass or less of the entire semiconductor fine particle dispersion.
In addition to the sol-gel method described above, a method of preparing a semiconductor fine particle dispersion is a method of depositing fine particles in a solvent and using them as they are when synthesizing a semiconductor. Ultrafine particles are irradiated with ultrasonic waves. Or a method of mechanically pulverizing and crushing using a mill or mortar. As the dispersion solvent, water and / or various organic solvents can be used. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, citronellol and α-terpineol, ketones such as acetone, esters such as ethyl acetate, dichloromethane, acetonitrile and the like.
In the dispersion, if necessary, for example, a polymer such as polyethylene glycol, butyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, a surfactant, an acid, a chelating agent, or the like may be used in a small amount as a dispersion aid. However, most of these dispersing aids are preferably removed by a filtration method, a method using a separation membrane, a centrifugal method or the like before the step of forming a film on a conductive support. In the semiconductor fine particle dispersion, the solid content other than the semiconductor fine particles can be 10% by mass or less of the total dispersion. This concentration is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less. More preferably, it is 0.5% or less, and particularly preferably 0.2%. That is, in the semiconductor fine particle dispersion, the solid content other than the solvent and the semiconductor fine particles can be 10% by mass or less of the entire semiconductor fine dispersion. It is preferable to consist essentially of semiconductor fine particles and a dispersion solvent.
If the viscosity of the semiconductor fine particle dispersion is too high, the dispersion will aggregate and cannot be formed into a film. Conversely, if the viscosity of the semiconductor fine particle dispersion is too low, the liquid will flow and cannot be formed into a film. is there. Therefore, the viscosity of the dispersion is preferably 10 to 300 N · s / m ² at 25 ° C. More preferably, it is 50 to 200 N · s / m ² at 25 ° C.

As a method for applying the semiconductor fine particle dispersion, a roller method, a dip method, or the like can be used as an application method. Moreover, an air knife method, a blade method, etc. can be used as a metering method. Further, the application system method and the metering system method can be made the same part. The wire bar method disclosed in Japanese Patent Publication No. 58-4589, the slide hopper method described in US Pat. The method and the curtain method are preferable. It is also preferable to apply by a spin method or a spray method using a general-purpose machine. As the wet printing method, intaglio, rubber plate, screen printing and the like are preferred, including the three major printing methods of letterpress, offset and gravure. From these, a preferred film forming method is selected according to the liquid viscosity and the wet thickness. Further, since the semiconductor fine particle dispersion has a high viscosity and has a viscous property, it may have a strong cohesive force and may not be well adapted to the support during coating. In such a case, by performing cleaning and hydrophilization of the surface by UV ozone treatment, the binding force between the applied semiconductor fine particle dispersion and the surface of the conductive support increases, and the semiconductor fine particle dispersion can be easily applied.
The preferred thickness of the entire semiconductor fine particle layer is 0.1 to 100 μm. The thickness of the semiconductor fine particle layer is further preferably 1 to 30 μm, and more preferably 2 to 25 μm. The amount of the semiconductor fine particles supported per 1 m ² of the support is preferably 0.5 g to 400 g, more preferably 5 to 100 g.

The applied semiconductor fine particle layer is subjected to heat treatment in order to enhance the electronic contact between the semiconductor fine particles and to improve the adhesion to the support and to dry the applied semiconductor fine particle dispersion. . By this heat treatment, a porous semiconductor fine particle layer can be formed. In addition, the semiconductor fine particle layer may be formed by a known method as appropriate according to the characteristics and application of the member. For example, the materials, preparation methods, and manufacturing methods described in Japanese Patent Application Laid-Open No. 2001-291534 can be referred to, and are cited in this specification.
In addition to heat treatment, light energy can also be used. For example, when titanium oxide is used as the semiconductor fine particles, the surface may be activated by applying light absorbed by the semiconductor fine particles such as ultraviolet light, or only the surface of the semiconductor fine particles may be activated by laser light or the like. Can do. By irradiating the semiconductor fine particles with light absorbed by the fine particles, the impurities adsorbed on the particle surface are decomposed by the activation of the particle surface, and can be brought into a preferable state for the above purpose. When heat treatment and ultraviolet light are combined, it is preferable that heating be performed at 100 ° C. or higher and 250 ° C. or lower, or preferably 100 ° C. or higher and 150 ° C. or lower, while irradiating the semiconductor fine particles with light absorbed by the fine particles. Thus, by photoexciting the semiconductor fine particles, impurities mixed in the fine particle layer can be washed by photolysis, and physical bonding between the fine particles can be strengthened.

In addition, the semiconductor fine particle dispersion may be applied to the conductive support, and other treatments may be performed in addition to heating and light irradiation. Examples of preferred methods include energization and chemical treatment.
A pressure may be applied after application, and examples of a method for applying pressure include Japanese Patent Application Publication No. 2003-500857. Examples of light irradiation include JP-A No. 2001-357896. Examples of plasma, microwave, and energization include JP-A-2002-353453. Examples of the chemical treatment include JP-A-2001-357896.

The method for coating the above-mentioned semiconductor fine particles on the conductive support is not only the method for coating the above-mentioned semiconductor fine particle dispersion on the conductive support, but also the semiconductor fine particle precursor described in Japanese Patent No. 2664194. A method such as a method of obtaining a semiconductor fine particle film by coating on a conductive support and hydrolyzing with moisture in the air can be used.
Examples of the precursor include (NH ₄ ) ₂ TiF ₆ , titanium peroxide, metal alkoxide / metal complex / metal organic acid salt, and the like.
Also, a method of forming a semiconductor film by applying a slurry in which a metal organic oxide (such as an alkoxide) coexists, and heat treatment, light treatment, etc., a slurry in which an inorganic precursor coexists, titania dispersed in the slurry pH The method which specified the property of particle | grains is mentioned. A binder may be added to these slurries in a small amount, and examples of the binder include cellulose, fluoropolymer, crosslinked rubber, polybutyl titanate, carboxymethyl cellulose and the like.
Techniques related to the formation of semiconductor fine particles or precursor layers thereof include corona discharge, plasma, a method of hydrophilizing by physical methods such as UV, a chemical treatment with alkali, polyethylenedioxythiophene and polystyrenesulfonic acid, polyaniline, etc. For example, formation of an interlayer film for bonding may be mentioned.

  As a method of coating the semiconductor fine particles on the conductive support, (2) the dry method and (3) other methods may be used in combination with the above (1) wet method. (2) As a dry method, JP 2000-231943 A is preferable. (3) As other methods, JP-A-2002-134435 is preferable.

Examples of the dry method include vapor deposition, sputtering, and aerosol deposition method. Further, electrophoresis or electrodeposition may be used.
Moreover, after producing a coating film once on a heat-resistant board | substrate, you may use the method of transcribe | transferring to films, such as a plastics. Preferably, a method of transferring via EVA described in JP-A No. 2002-184475, a semiconductor layer / conductive layer on a sacrificial substrate containing an inorganic salt that can be removed with ultraviolet rays and an aqueous solvent described in JP-A No. 2003-98977 And a method of removing the sacrificial substrate after transfer to an organic substrate.

  The semiconductor fine particles preferably have a large surface area so that many dyes can be adsorbed. For example, in a state where the semiconductor fine particles are coated on the support, the surface area is preferably 10 times or more, more preferably 100 times or more the projected area. Although there is no restriction | limiting in particular in this upper limit, Usually, it is about 5000 times. JP-A-2001-93591 and the like are preferable as the structure of the semiconductor fine particles.

In general, as the thickness of the semiconductor fine particle layer increases, the amount of dye that can be supported per unit area increases, so that the light absorption efficiency increases. However, the diffusion distance of the generated electrons increases, and the loss due to charge recombination also increases. The preferred thickness of the semiconductor fine particle layer varies depending on the use of the device, but is typically 0.1 to 100 μm. When using as a photoelectrochemical cell, it is preferable that it is 1-50 micrometers, and it is more preferable that it is 3-30 micrometers. The semiconductor fine particles may be heated at a temperature of 100 to 800 ° C. for 10 minutes to 10 hours in order to adhere the particles to each other after being applied to the support. When glass is used as the support, the film forming temperature is preferably 400 to 600 ° C.
When a polymer material is used as the support, it is preferably heated after film formation at 250 ° C. or lower. In this case, the film forming method may be any one of (1) a wet method, (2) a dry method, and (3) an electrophoresis method (including an electrodeposition method), preferably (1) a wet method, or ( 2) A dry method, more preferably (1) a wet method.
The coating amount of the semiconductor fine particles per 1 m ² of the support is preferably 0.5 to 500 g, more preferably 5 to 100 g.

(F) Photoreceptor layer A photoreceptor layer can be formed by adsorbing a dye to the semiconductor fine particle layer produced as described above.
In order to adsorb the dye to the semiconductor fine particles, it is preferable to immerse the well-dried semiconductor fine particles in a dye adsorbing dye solution composed of a solution and a dye for a long time. The solution used for the dye solution for dye adsorption can be used without particular limitation as long as the solution can dissolve the dye. For example, ethanol, methanol, isopropanol, toluene, t-butanol, acetonitrile, acetone, n-butanol and the like can be used. Among these, ethanol and toluene can be preferably used.
You may heat the pigment | dye solution for pigment | dye adsorption which consists of a solution and a pigment | dye to 50 to 100 degreeC as needed. The adsorption of the dye may be performed before or after application of the semiconductor fine particles. Further, the semiconductor fine particles and the dye may be applied and adsorbed simultaneously. Unadsorbed dye is removed by washing. When baking a coating film, it is preferable to adsorb | suck a pigment | dye after baking. It is particularly preferable that the dye is quickly adsorbed after the baking and before water adsorbs on the surface of the coating film. The dye to be mixed is selected so as to make the wavelength range of photoelectric conversion as wide as possible. When mixing the dyes, it is preferable to prepare a dye solution for dye adsorption by dissolving all the dyes.

The total amount of the dye used is preferably 0.01 to 100 mmol, more preferably 0.1 to 50 mmol, and particularly preferably 0.1 to 10 mmol per 1 m ² of the support. In this case, it is preferable that the usage-amount of a pigment | dye shall be 5 mol% or more.
Further, the adsorption amount of the dye to the semiconductor fine particles is preferably 0.001 to 1 mmol, more preferably 0.1 to 0.5 mmol, with respect to 1 g of the semiconductor fine particles. By using such a dye amount, a sensitizing effect in a semiconductor can be sufficiently obtained.

Further, a colorless compound may be co-adsorbed for the purpose of reducing the interaction between dyes such as association. Examples of the hydrophobic compound to be co-adsorbed include steroid compounds having a carboxyl group (for example, cholic acid and pivaloyl acid).
After adsorbing the dye, the surface of the semiconductor fine particles may be treated with amines. Preferred amines include 4-tert-butylpyridine and polyvinylpyridine. These may be used as they are in the case of a liquid, or may be used by dissolving in an organic solvent.

(G) Counter electrode The counter electrode (counter electrode) serves as the positive electrode of the photoelectrochemical cell. The counter electrode is usually synonymous with the conductive support described above, but the support is not necessarily required in a configuration in which the strength is sufficiently maintained. However, having a support is advantageous in terms of hermeticity. Examples of the material for the counter electrode include platinum, carbon, conductive polymer, and the like. Preferable examples include platinum, carbon, and conductive polymer.

As the structure of the counter electrode, a structure having a high current collecting effect is preferable. Preferable examples include JP-A-10-505192.
As the light receiving electrode, a composite electrode such as titanium oxide and tin oxide (TiO ₂ / SnO ₂ ) may be used. Examples of mixed electrodes other than titania include JP-A Nos. 2001-185243 and 2003-282164.

(H) Configuration of photoelectric conversion element As a configuration of the photoelectric conversion element, a conductive support (electrode layer), a photoelectric conversion layer (photosensitive layer and charge transfer layer), a hole transport layer, a conductive layer, and a counter electrode layer are sequentially formed. Can be stacked. A hole transport material that functions as a p-type semiconductor can be used as a hole transport layer. As a preferred hole transport layer, for example, an inorganic or organic hole transport material can be used. Examples of the inorganic hole transport material include CuI, CuO, and NiO. Examples of the organic hole transport material include high molecular weight materials and low molecular weight materials, and examples of the high molecular weight materials include polyvinyl carbazole, polyamine, and organic polysilane. Moreover, as a low molecular weight thing, a triphenylamine derivative, a stilbene derivative, a hydrazone derivative, a phenamine derivative etc. are mentioned, for example. Among these, organic polysilanes are preferred because, unlike conventional carbon-based polymers, σ electrons delocalized along the main chain Si contribute to photoconductivity and have high hole mobility (Phys. Rev. B, 1987, vol. 35, p.

The conductive layer is not particularly limited as long as it has good conductivity, and examples thereof include inorganic conductive materials, organic conductive materials, conductive polymers, and intermolecular charge transfer complexes. Among them, an intermolecular charge transfer complex formed from a donor material and an acceptor material is preferable. Among these, what was formed from the organic donor and the organic acceptor can be used preferably. The donor material is preferably a material rich in electrons in the molecular structure. For example, organic donor materials include those having a substituted or unsubstituted amine group, hydroxyl group, ether group, selenium or sulfur atom in the π-electron system of the molecule, specifically, phenylamine-based, triphenylmethane , Carbazole, phenol, and tetrathiafulvalene materials. As the acceptor material, those lacking electrons in the molecular structure are preferable. For example, organic acceptor materials include fullerenes, those having a substituent such as a nitro group, a cyano group, a carboxyl group or a halogen group in the π-electron system of the molecule, specifically, PCBM, benzoquinone, naphthoquinone, etc. Quinone, fluoroenone, chloranil, bromanyl, tetracyanoquinodimethane, tetracyanoethylene and the like.
The thickness of the conductive layer is not particularly limited, but is preferably such that the porous layer can be completely filled.

  The element may have a structure in which a first electrode layer, a first photoreceptor layer, a conductive layer, a second photoreceptor layer, and a second electrode layer are sequentially stacked. In this case, the dyes used in the first photoreceptor layer and the second photoreceptor layer may be the same or different, and if they are different, it is preferable that the absorption spectra are different. In addition, structures and members that are applied to this type of electrochemical element can be applied as appropriate.

The light receiving electrode may be a tandem type in order to increase the utilization rate of incident light. Preferred examples of the tandem type configuration include those described in JP-A Nos. 2000-90989 and 2002-90989.
A light management function for efficiently performing light scattering and reflection inside the light receiving electrode layer may be provided. Preferably, the thing of Unexamined-Japanese-Patent No. 2002-93476 is mentioned.

In order to prevent reverse current due to direct contact between the electrolyte and the electrode, it is preferable to form a short-circuit prevention layer between the conductive support and the photoreceptor layer. Preferable examples include Japanese Patent Application Laid-Open No. 06-507999.
In order to prevent contact between the light receiving electrode and the counter electrode, it is preferable to use a spacer or a separator. A preferable example is JP-A No. 2001-283941.

  Cell and module sealing methods include polyisobutylene thermosetting resin, novolak resin, photo-curing (meth) acrylate resin, epoxy resin, ionomer resin, glass frit, method using aluminum alkoxide for alumina, low melting point glass paste It is preferable to use a laser melting method. When glass frit is used, powder glass mixed with acrylic resin as a binder may be used.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.

Synthesis Example 1 (Preparation of Exemplified Dye (X-26))
Exemplified dye (X-26) was prepared according to the method of the following scheme.

(I) Preparation of compound (d-1-2) 25 g of compound (d-1-1), 33.8 g of Pd ₂ (dba) ₃ , 8.6 g of triphenylphosphine, 2.5 g of copper iodide, 1-he 25.2 g of puttin was stirred in a mixed solution of 70 mL of triethylamine and 50 mL of tetrahydrofuran (THF) at room temperature, and stirred at 80 ° C. for 4.5 hours. After concentration, 26.4 g of compound (d-1-2) was obtained by purification by column chromatography.

(Ii) Preparation of Compound (d-1-4) 6.7 g of Compound (d-1-3) was dissolved in 200 mL of tetrahydrofuran at −15 ° C. under a nitrogen atmosphere, and separately prepared LDA (lithium diisopropylamide) was used as the compound. 2.5 equivalents of (d-1-3) was added dropwise and stirred for 75 minutes. Thereafter, a solution of 15 g of compound (d-1-2) dissolved in 30 mL of tetrahydrofuran was dropped, and the mixture was stirred at 0 ° C. for 1 hour and then stirred at room temperature for 17 hours. After concentration, 150 mL of water was added, liquid separation and extraction were performed with 150 mL of methylene chloride, the organic layer was washed with brine, and the organic layer was concentrated. The obtained crystal was recrystallized from methanol to obtain 18.9 g of compound (d-1-4).

(Iii) Preparation of Compound (d-1-5) 13.2 g of Compound (d-1-4) and 1.7 g of PPTS (pyridinium paratoluenesulfonic acid) are added to 1000 mL of toluene and heated under a nitrogen atmosphere for 5 hours. Reflux was performed. After concentration, liquid separation was performed with saturated aqueous sodium hydrogen carbonate and methylene chloride, and the organic layer was concentrated. The obtained crystals were recrystallized from methanol and methylene chloride to obtain 11.7 g of compound (d-1-5).

(Iv) Preparation of Exemplified Dye (X-26) 4.0 g of compound (d-1-5) and 2.2 g of compound (d-1-6) were added to 60 mL of DMF (dimethylformamide) at 70 ° C. for 4 hours. Stir. Thereafter, 2.1 g of the compound (d-1-7) was added and the mixture was heated and stirred at 160 ° C. for 3.5 hours. Thereafter, 19.0 g of ammonium thiocyanate was added and stirred at 130 ° C. for 5 hours. After concentration, 1.3 mL of water was added and filtered, and washed with diethyl ether. The crude product was dissolved in a methanol solution together with TBAOH (tetrabutylammonium hydroxide) and purified with a Sephadex LH-20 column. The main layer fraction was collected and concentrated, and then 0.2 M nitric acid was added. The precipitate was filtered and washed with water and diethyl ether to obtain 600 mg of a crude product. The crude product was dissolved in a methanol solution, 1M nitric acid was added, the precipitate was filtered, and washed with water and diethyl ether to obtain 570 mg of Exemplified dye (X-26).

The structure of the obtained exemplary dye (X-26) was confirmed by NMR measurement.
¹ H-NMR (DMSO-d ₆ , 400 MHz): δ (ppm) in aromatic regions: 9.37 (1H, d), 9.11 (1H, d), 9.04 (1H, s), 8. 89 (2H), 8.74 (1H, s), 8.26 (1H, d), 8.10-7.98 (2H), 7.85-7.73 (2H), 7.60 (1H , D), 7.45-7.33 (2H), 7.33-7.12 (5H, m), 6.92 (1H, d)

  About the obtained exemplary pigment | dye (X-26), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 568 nm.

Synthesis Example 2 (Preparation of Exemplified Dye (X-30))
Compound (d-2-4) was prepared according to the method of the following scheme, and compound (d-1-2) was replaced with compound (d-2-4) in the same manner as Exemplified dye (X-26). Example dye (X-30) was prepared.

  About the obtained exemplary pigment | dye (X-30), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 570 nm.

Synthesis Example 3 (Preparation of Exemplified Dye (X-32))
Compound (d-3-2) was prepared according to the method of the following scheme, and was the same as Exemplified dye (X-26) except that compound (d-1-2) was replaced with compound (d-3-2). Example dye (X-32) was prepared.

  About the obtained exemplary pigment | dye (X-32), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 574 nm.

Synthesis Example 4 (Preparation of Exemplified Dye (X-31))
Compound (d-4-2) was prepared according to the method of the following scheme, and compound (d-1-2) was replaced with compound (d-4-2) in the same manner as Exemplified dye (X-26). Example dye (X-31) was prepared.

  About the obtained exemplary pigment | dye (X-31), when it prepared so that the density | concentration of pigment | dye might be set to 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 588 nm.

Synthesis Example 5 (Preparation of Exemplified Dye (X-33))
Compound (d-5-6) was prepared according to the method of the following scheme, and compound (d-1-5) was replaced with compound (d-5-6) in the same manner as Exemplified dye (X-26). Thus, Exemplified dye (X-33) was prepared.

  About the obtained exemplary pigment | dye (X-33), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 570 nm.

Synthesis Example 6 (Preparation of Exemplified Dye (X-34))
Compound (d-6-3) was prepared according to the method of the following scheme, and was the same as Exemplified dye (X-26) except that compound (d-1-5) was replaced with compound (d-6-3). Example dye (X-34) was prepared.

  About the obtained exemplary pigment | dye (X-34), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 571 nm.

Synthesis Example 7 (Preparation of Exemplified Dye (X-35))
In the preparation of the exemplified dye (X-30), the exemplified dye (X-35) was prepared in the same manner except that the following compound (d-7-1) was used instead of the compound (d-2-2). did.

  About the obtained exemplary pigment | dye (X-35), when it prepared so that the density | concentration of a pigment | dye might be 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 574 nm.

Synthesis Example 8 (Preparation of Exemplified Dye (X-36))
Exemplified dye (X-36) was prepared in the same manner as Exemplified dye (X-26) below according to the method of the following scheme.

  About the obtained exemplary pigment | dye (X-36), when it prepared so that the density | concentration of pigment | dye might be set to 8.5 micromol / L with an ethanol solvent, and the spectral absorption measurement was performed, the absorption maximum wavelength was 580 nm.

The same applies to the exemplified dye (X-22), the exemplified dye (X-23), the exemplified dye (X-24), the exemplified dye (X-25), the exemplified dye (X-27), and the exemplified dye (X-28). It was prepared by the method.
As comparative dyes, the following dyes (X-19), (X-20) and (X-21) Am. Chem. Soc., 2001, vol. 123, p. It was prepared with reference to the method described in 1613-1624.

<Evaluation of dye>
The maximum absorption wavelengths of the dyes (X-19) to (X-36) were measured. The results are shown in Table 1. The measurement was performed with a spectrophotometer (U-4100 (trade name), manufactured by Hitachi High-Tech), and the solution was adjusted to a concentration of 2 μM using THF: ethanol = 1: 1.

<Preparation of Dispersion of Semiconductor Fine Particles (II) Containing Locally Two or More Kinds of Metals or Metal Compounds>
Semiconductor fine particles (I) were prepared, and semiconductor fine particles (II) comprising two or more kinds of metals or metal compounds locally were prepared using the fine particles.
1. Preparation of semiconductor fine particles (I) (1) Tin oxide (SnO ₂ )
Puratronic (trade name) manufactured by Alfa Aesar was used without purification. The particle size of the tin oxide was measured by a laser diffraction particle size distribution analyzer (Mastersizer (trade name) manufactured by MALVERN), and it was 20 to 30 nm.
(2) Titanium oxide (TiO ₂ )
Acetic acid (0.2 mol) was added dropwise to Titanium isopropoxide (0.2 mol) at room temperature and stirred for 15 minutes. Thereafter, 290 mL of distilled water was added and stirred for 1 hour. After 1 hour, 65% aqueous HNO ₃ solution was added, heated to 78 ° C. over 40 minutes, and stirred for 75 minutes. After stirring, 290 mL of distilled water was added to prepare a titanium oxide sol solution (crystal system: amorphous). This titanium oxide sol solution was stirred at 250 ° C. for 12 hours using an autoclave to obtain a titanium oxide particle-dispersed aqueous solution.
This aqueous solution was filtered to obtain titanium oxide. The crystal system of the obtained titanium oxide was anatase type. The particle size of the titanium oxide was measured by a laser diffraction type particle size distribution analyzer (Mastersizer (trade name) manufactured by MALVERN), and it was 10 to 30 nm.

2.2 Preparation of semiconductor fine particles (II) locally having two or more kinds of metals or metal compounds (1) Preparation of core-shell type semiconductor fine particles (a) Aluminum oxide (Al ₂ O ₃ ) shell portion Preparation of semiconductor fine particles (II) The semiconductor fine particles (I) were dispersed in a 2-150 mM trimethylaluminum aqueous solution and reacted for 8 seconds at 200 ° C. to obtain semiconductor fine particles (II). When the obtained semiconductor fine particles were observed with a transmission electron microscope (TEM), they were semiconductor fine particles (II) having a core-shell structure in which tin oxide or titanium oxide was used as a core portion and aluminum oxide was used as a shell portion. all right. When the volume ratio of the core: shell was observed with TEM, it was 90:10 to 98: 2. The particle size of the semiconductor fine particles was measured with a laser diffraction particle size distribution analyzer (Mastersizer (trade name) manufactured by MALVERN), and it was 20 to 30 nm.

(B) Preparation of semiconductor fine particles (II) having magnesium oxide (MgO) as a shell portion The semiconductor fine particles (I) are immersed in an ethanol solution (60 to 70 ° C.) in which 2-150 mM magnesium acetate is dissolved for 1 minute. After washing, firing was performed at 500 ° C. to obtain semiconductor fine particles (II). When the obtained semiconductor fine particles were observed with a transmission electron microscope (TEM), they were semiconductor fine particles (II) having a core-shell structure in which tin oxide or titanium oxide was used as a core portion and magnesium oxide was used as a shell portion. all right. When the volume ratio of core: shell was observed with TEM in the same manner as described above, it was 90:10 to 98: 2. When the particle size of the semiconductor fine particles was measured by the same method as described above, it was 20 to 30 nm.

(C) Preparation of semiconductor fine particles (II) having titanium oxide (TiO ₂ ) as a shell portion The semiconductor fine particles (I) were immersed in a 2 to 20 mM TiCl ₄ aqueous solution (70 ° C.) for 1 hour, washed, and then 500 Semiconductor fine particles (II) were obtained by firing at 0 ° C. When the obtained semiconductor fine particles were observed with a transmission electron microscope (TEM), they were semiconductor fine particles (II) having a core-shell structure in which tin oxide or titanium oxide was used as a core portion and titanium oxide was used as a shell portion. all right. When the volume ratio of core: shell was observed with TEM in the same manner as described above, it was 90:10 to 98: 2. When the particle size of the semiconductor fine particles was measured by the same method as described above, it was 20 to 30 nm.

(D) Preparation of semiconductor fine particles (II) having calcium carbonate (CaCO ₃ ) as a shell portion The semiconductor fine particles (I) are immersed in an aqueous solution of 1 to 3% by mass of calcium acetate for a predetermined time and fired at 525 ° C. As a result, semiconductor fine particles (II) were obtained. When the obtained semiconductor fine particles were observed with a transmission electron microscope (TEM), they were semiconductor fine particles (II) having a core-shell structure in which tin oxide or titanium oxide was used as a core portion and calcium carbonate was used as a shell portion. all right. When the volume ratio of core: shell was observed with TEM in the same manner as described above, it was 90:10 to 98: 2. When the particle size of the semiconductor fine particles was measured by the same method as described above, it was 20 to 30 nm.

(E) Preparation of semiconductor fine particles (II) having two or more kinds of materials as shell portions Semiconductor fine particles having two or more types of materials as shell portions are repeatedly subjected to the methods described in (a) to (d) above. It was prepared by. When the obtained semiconductor fine particles are observed with a transmission electron microscope (TEM), they are semiconductor fine particles (II) having a core-shell structure in which two or more kinds of materials used for the core portion are shell portions. I understood. When the volume ratio of core: shell was observed with TEM in the same manner as described above, it was 90:10 to 98: 2. When the particle size of the semiconductor fine particles was measured by the same method as described above, it was 20 to 40 nm.

(F) Addition of conductive material Graphene was used as the conductive material. Graphene was prepared from Qingdao (trade name) manufactured by Qingdao Tianhe Graphite (People's Republic of China) using flaky kraftite (average particle size: 4 μm, purity 99.95%).
5 g of the above graphite and 3.75 g of NaNO ₃ were added to the flask, and 375 mL of H ₂ SO ₄ was added and stirred under ice cooling. Thereafter, 22.5 g of KMnO ₄ was added over about 1 hour. After stirring for 2 hours under ice cooling, the mixture was stirred at room temperature for 5 days. Thereafter, 700 mL of a 5 wt% aqueous sulfuric acid solution was added and stirred for 1 hour, and the temperature was maintained at 98 ° C. The resulting mixture was stirred at 98 ° C. for an additional 2 hours. After the temperature was lowered to 60 ° C., 15 mL of hydrogen peroxide was added and stirred at room temperature for 2 hours. In order to remove impurity ions, the obtained mixture was purified by performing the following operation 15 times.
(Purification method)
Centrifuge and remove the supernatant. _{3wt% H 2 SO 4 /0.5wt%H 2} O 2 mixed aqueous solution was added 2L of strongly performing sonication for 30 minutes with stirring. Then, it is washed 3 times with 2 L of 3 wt% HCl aqueous solution and once with distilled water. The obtained aqueous solution is purified by passing through an ion exchange resin (D301T, Nankai University Chemical Plant).
Purification was performed by the above method, and graphene was obtained by removing distilled water. It was confirmed by X-ray photoelectron spectroscopy and a scanning electron microscope that the purified product was graphene. About what added graphene to semiconductor fine particles, 1 mass% was blended with respect to semiconductor fine particles.

(2) Preparation of metal doped semiconductor fine particles Semiconductor fine particles of titanium oxide doped with Nb were prepared by the following method.
Niobium powder (0.002 mol) and Tetrabutyl Titanete (0.018 mol) were added to a H ₂ O ₂ / NH ₃ mixed solution (v / v = 5/1) and stirred to prepare a precursor. The precursor was heated to 80 ° C. to remove excess H ₂ O ₂ and NH ₃ and then heated at 180 ° C. for 20 hours using an autoclave. The obtained dispersion was washed with deionized water having a pH of 7 or less and dried at 100 ° C. for 6 hours to obtain semiconductor fine particles of titanium oxide doped with Nb. It was confirmed by XRD or STEM that the semiconductor fine particles were doped with Nb. It was 10-30 nm when the particle size of the semiconductor fine particle was measured by the method similar to the above.

3. Preparation of Semiconductor Fine Particle (II) Dispersion Liquid Each of the semiconductor fine particles (II) was dispersed in an α-terpineol solution containing 5% by mass of ethyl cellulose to obtain a dispersion of 15% by mass of semiconductor fine particles (II). This dispersion was uniformly dispersed and mixed using a rotating / revolving mixing conditioner.

4). Preparation of Other Semiconductor Fine Particle Dispersions In Comparative Examples 50 to 105 shown in the following table, a mixture of two kinds of fine particles 1 and fine particles 2 shown in the following table at a mass ratio of 1: 1 was used. Of the fine particles 2 shown in the table below, “TiO ₂ / MgO” means that TiO ₂ fine particles are immersed in an ethanol solution (60 to 70 ° C.) in which 2-150 mM magnesium acetate is dissolved for 1 minute and washed. Thereafter, fine particles prepared by firing at 500 ° C.

<Adsorption evaluation>
On the glass substrate, tin oxide doped with fluorine was formed as a transparent conductive film by sputtering. Next, the semiconductor fine particle dispersion was applied to a transparent conductive film and heated at 500 ° C. to form a semiconductor fine particle layer. The thickness of the semiconductor fine particle layer thus obtained was 10 μm, and the coating amount of the semiconductor fine particles was 20 g / m ² .
The semiconductor fine particle layer formed on the glass substrate was immersed in a 10% ethanol solution of the dyes shown in the following table at 40 ° C. for 3 hours in the dark. The light-receiving electrode obtained by adsorbing the dye was desorbed using a 10% TBAOH methanol solution, and the initial adsorption amount of each dye was quantified by measuring the absorption spectrum. B what adsorption amount is less than ^{2.0 × 10 -4 mM / cm 2} , the 2.0 × 10 ^-4 mM / cm ² or more of the the A.

<Evaluation of photoelectric conversion efficiency>
(Preparation of photoelectric conversion element)
A light-receiving electrode produced by the same method as the above adsorptivity evaluation was produced. Thereafter, the same semiconductor fine particle dispersion was applied to the light receiving electrode and heated at 500 ° C. to form an insulating porous body. Next, the glass substrate on which the above-mentioned insulating porous body was formed was immersed in a 10% ethanol solution of the dyes shown in Tables 2 to 9 for 12 hours. The dyed glass was immersed in a 10% ethanol solution of 4-tert-butylpyridine for 30 minutes, then washed with ethanol and air dried. The thickness of the photosensitive layer thus obtained was 10 μm, and the coating amount of semiconductor fine particles was 20 g / m ² .
Thereafter, the semiconductor fine particle electrode was disposed opposite to the platinum sputtered FTO substrate through a 50 μm thick thermoplastic polyolefin resin sheet, and the resin sheet portion was melted by heat to fix the bipolar plate.
In addition, the electrolyte solution was injected from the injection port of the electrolyte solution previously opened in the platinum sputter | spatter electrode side, and it filled between electrodes. Furthermore, the peripheral part and the electrolyte solution injection port were finally sealed with an epoxy-based sealing resin, and a silver paste was applied to the current collecting terminal part to obtain a photoelectric conversion element.
As the electrolytic solution, a methoxypropionitrile solution of dimethylpropylimidazolium iodide (0.5 mol / L) and iodine (0.1 mol / L) was used.

(Measurement of photoelectric conversion efficiency)
Simulated sunlight containing no ultraviolet rays was generated by passing the light of a 500 W xenon lamp (manufactured by Ushio) through an AM1.5G filter (manufactured by Oriel) and a sharp cut filter (KenkoL-42, trade name). The intensity of this light was 89 mW / cm ² . The produced photoelectric conversion element was irradiated with this light, and the generated electricity was measured with a current-voltage measuring device (Caseley 238 type, trade name). The result of having measured the initial value of the conversion efficiency of the photoelectrochemical cell calculated | required by this was shown to Tables 2-9. As a result, conversion efficiency is 4% or more and less than 5%, E, 5% or more and less than 6% D, 6% or more and less than 7% C, 7% or more and less than 8% B, A value of 8% or more and less than 9% was evaluated as A, and A, B, and C were regarded as acceptable. As for durability, the conversion efficiency after 500 hours with respect to the initial value of the conversion efficiency is evaluated as A with a conversion efficiency of 90% or more, B with a conversion efficiency of 80% or more and less than 90%, and C with a conversion efficiency of less than 80%. , A and B were accepted.

As can be seen from Tables 4 and 7, as can be seen from Comparative Examples 1-21 and 26-46, when the dye represented by the general formula (1) is not used, or the semiconductor fine particles are two or more metals or metal compounds In the case where it is not constituted from the above, the initial value of the conversion efficiency is often insufficient, and the durability is not acceptable. Moreover, as can be seen from Tables 8 and 9, in the case of simply mixing the semiconductor fine particles, either the initial value or the durability of the photoelectric conversion efficiency was rejected, and most of them were rejected.
On the other hand, when the semiconductor fine particles used locally include two or more kinds of metals or metal compounds and the dye represented by the general formula (1) is used, the initial value of the photoelectric conversion efficiency is It was found to be excellent in durability.

DESCRIPTION OF SYMBOLS 1 Conductive support body 2 Photosensitive layer 21 Sensitizing dye 22 Semiconductor fine particle 3 Charge transfer body layer 4 Counter electrode 5 Photosensitive electrode 6 External circuit 10 Photoelectric conversion element 100 Photoelectrochemical cell

Claims (6)

A photoelectric conversion element comprising a conductive support, a photosensitive layer composed of a semiconductor fine particle layer containing a dye, a charge transfer layer, and a counter electrode, wherein the semiconductor fine particles are two or more kinds of metals or metal compounds And the dye is a compound represented by the following general formula (1):
The semiconductor fine particles are
A metal chalcogenide or metal carbonate selected from the group consisting of aluminum oxide, magnesium oxide, calcium carbonate, titanium oxide and titanium oxide / magnesium oxide, having as its core a metal chalcogenide selected from the group consisting of titanium oxide and tin oxide Obtained by doping semiconductor fine particles having a salt as a shell part or a metal chalcogenide selected from the group consisting of titanium oxide and tin oxide with at least one metal atom selected from the group consisting of Nb, V and Ta Semiconductor fine particles,
A photoelectric conversion element.

Mz (LL ¹ ) _m1 (LL ² ) _m2 (X) _m3 · (CI) _m4 General formula (1)

[Mz represents a Ru atom, LL ¹ is a bidentate ligand represented by the following general formula (2), and LL ² is a bidentate ligand represented by the following general formula (3). is there.
X represents an isothiocyanate group.
CI represents a counter ion that neutralizes the charge of the compound represented by the general formula (1).
m1 represents an integer of 1 or 2, and when m1 is 2, LL ¹ may be the same or different. m2 represents an integer of 0 or 1. m3 represents 2. m4 represents an integer of 0 to 3, and when m4 is 2 or more, CIs may be the same or different.

In the general formula (2), R ¹⁰¹ and R ¹⁰² each represent a carboxyl group. R ¹⁰³ and R ¹⁰⁴ each independently represent a substituent, and R ¹⁰⁵ and R ¹⁰⁶ each independently represent a group consisting of at least one selected from the group consisting of an alkyl group, an aryl group, and a heterocyclic group.
L ¹ and L ² each independently represents a conjugated chain composed of an ethenylene group and / or an ethynylene group.
a1 and a2 each independently represent an integer of 0 or 1. b1 and b2 each represents 0. d1 and d2 each independently represent an integer of 0 or 1. d3 represents 1.

In the general formula (3), Za, Zb and Zc each represent a nonmetallic atom group capable of forming a pyridine ring, and c represents 0. However, when a1 and a2 are each 0 in the general formula (2), each of two pyridine rings formed by Za and Zb has a carboxyl group as a substituent. ]   The photoelectric conversion element according to claim 1, wherein the semiconductor fine particles have a particle diameter of 1 to 1000 nm.   The photoelectric conversion element according to claim 1, wherein the semiconductor fine particles include an additive made of a conductive material.   The photoelectric conversion element according to claim 3, wherein the conductive material is graphene. In the general formula (1), LL ¹ is represented by the general formula (4-3), the photoelectric conversion element described in any one of claims 1-4.

[R ^{101 to} R ¹⁰⁴ , a 1, a 2, b 1, b 2, and d 3 have the same meaning as in general formula (2). R ¹²⁷ and R ¹²⁸ each independently represents an alkyl group or an alkynyl group. ] A photoelectrochemical cell provided with the photoelectric conversion element of any one of Claims 1-5.

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