TW201440287A - Photoelectric conversion element, dye-sensitzed solar cell, metal complex dye, dye solution, dye adsorption electrode for dye-sensitized solar cell and method for manufacturing dye-sensitized solar cell - Google Patents

Abstract

A photoelectric conversion element, a dye-sensitized solar cell, a dye solution and a method for manufacturing the dye-sensitized solar cell are provided. The photoelectric conversion element includes a conductive support, a photoreceptor layer containing electrolyte, a charge transfer body layer containing electrolyte and a counter electrode. The photoreceptor layer includes semiconductor particles carrying a metal complex dye represented by formula (I). M(LD)(LA)(Z).(CI) formula (I).

Description

Photoelectric conversion element, dye-sensitized solar cell, metal complex dye, dye solution, dye-sensitized electrode for dye-sensitized solar cell, and method for producing dye-sensitized solar cell

The present invention relates to a method for producing a photoelectric conversion element, a dye-sensitized solar cell, a metal complex dye, a dye solution, a dye adsorption electrode, and a dye-sensitized solar cell.

The photoelectric conversion element is used in various photo sensors, photocopiers, solar cells, and the like. In the photoelectric conversion element, a photoelectric conversion element using a metal, a photoelectric conversion element using a semiconductor, a photoelectric conversion element using an organic pigment or a dye, or a photoelectric conversion element obtained by combining these photoelectric conversion elements, and the like have been put into practical use. The way. In particular, solar cells using non-exhaustive solar energy require no fuel and use endless clean energy, and their formal practical use is expected. Among them, Solar cells have been researched and developed since very early. Countries also have policy considerations to promote their popularity. However, niobium is an inorganic material and naturally has limitations in terms of throughput and molecular modification.

Therefore, research on dye-sensitized solar cells is being carried out as much as possible. In particular, the research results of Graetzel and others at the University of Ecole Polytechnique Federale de Lausanne (EPFL) have become an opportunity. They use a structure in which a pigment containing a ruthenium complex is fixed on the surface of a porous titanium oxide film to achieve the same conversion efficiency as that of amorphous ruthenium. Therefore, the dye-sensitized solar cell has attracted the attention of researchers all over the world.

Heretofore, N3, N719, Z907, J2, and the like have been developed as metal complex dyes used in photoelectric conversion elements. However, in general, the conventional dye-sensitized solar cell has many cases in which the photoelectric conversion efficiency and durability are insufficient.

Previously, in the development of metal complex dyes, as a ligand on a metal, a combination of a bidentate ligand and a 2-dentate ligand or a 2-dental ligand and a 3-dentate was studied. A combination of a tridentate ligand (for example, refer to Patent Document 1 to Patent Document 3), but further research is required in order to improve durability.

Further, solar cells have become an energy source for replacing atomic power generation, and their attention and expectation have been improved, and further improvement in performance as a solar cell has been demanded.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] US Patent Application Publication No. 2012/0111410 book

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2009-51999

[Patent Document 3] International Publication No. 2009/131183

In the improvement of the photoelectric conversion efficiency and the improvement of the durability, the conventional metal complex dye including the metal complex dye described in Patent Document 1 is required in comparison with a solar battery using an inorganic material. Greatly improved and improved. In particular, the improvement of the durability of fate as an organic material is a difficult problem, so it is important to find a breakthrough in new development.

According to the study by the inventors of the present invention, it has been found that in addition to the above, there is a problem that the performance of the obtained photoelectric conversion element and the dye-sensitized solar cell is unstable, that is, even if it is produced in the same manner, the photoelectric conversion produced is performed. The same performance is not achieved between components or dye-sensitized solar cells.

In view of the above, it is an object of the present invention to provide a photoelectric conversion element, a dye-sensitized solar cell, and a metal containing metal which can stably maintain these properties in addition to the improvement in photoelectric conversion efficiency. A dye solution of a complex pigment, a dye adsorption electrode, and a method for producing a dye-sensitized solar cell.

In order to adsorb the surface of the semiconductor fine particles, the inventors of the present invention have studied the relationship between a ligand having an acidic group such as a carboxyl group and a ligand having no acidic group, and improved durability by improving the adsorption force. The interaction between the ligands such as the electronic interaction between the ligands has been studied, and as a result, a clue to solve the above problems has been obtained, and the present invention has been completed.

That is, the problem of the present invention can be achieved by the following means.

(1) A photoelectric conversion element comprising a conductive support, a photoreceptor layer containing an electrolyte, a charge transfer body layer containing an electrolyte, and a counter electrode, wherein the photoreceptor layer has a structure represented by the following formula (I) Semiconductor complex pigment semiconductor fine particles: M (LD) (LA) (Z). (CI) Formula (I)

In the formula (I), M represents a metal ion.

LD represents a bidentate ligand represented by the following formula (DL-1).

LA represents a tridentate ligand represented by the following formula (AL-1) or formula (AL-2).

Z represents a monodentate ligand.

CI represents the counter ion necessary to neutralize the charge.

In the formula (DL-1), the ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring. Y ¹ represents a carbon atom or a nitrogen atom, and ring C1 represents a monocyclic or condensed ring aryl ring or heteroaryl ring which is coordinated to M by a carbo anion. R ^A is a group represented by the following formula (U). R ^B represents a substituent. R ^C represents a halogen atom, an alkyl group, a cycloalkyl group, a decyl group, an alkylsulfinylene group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group or a nitro group. A1 represents an integer of 1 to 4, a2 represents an integer of 0 to 3, and a3 represents an integer of 0 or more. In the case where a plurality of R ^A , R ^B and R ^C are respectively present, these may be the same or different.

In the formula (U), L ^u represents a single bond, an ethenylene or an ethynylene. The ring X ^u represents an extended aryl group or a heteroaryl group, and q represents an integer of 0 to 2. R ^u represents a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group. Wherein, in the case where the ring X ^u is an extended aryl group, R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group. Nu represents an integer of 1 to 4. When nu is 2 or more, a plurality of R ^u may be the same or different, or may be bonded to each other to form a ring.

Formula (AL-1) formula (AL-2)

In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ each independently represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which any of these protons are dissociated. . R ^AL represents a substituent, and b1 represents an integer of 0-4.

(2) The photoelectric conversion element according to (1), wherein M is Fe ²⁺ , Ru ²⁺ or Os ²⁺ .

(3) The photoelectric conversion element according to (1) or (2), wherein the ring C1 is a thiophene ring, a furan ring, a pyrrole ring or a benzene ring.

The photoelectric conversion element according to any one of (1) to (3) wherein the ring X ^u is a heteroaryl ring group.

The photoelectric conversion element according to any one of (1) to (4) wherein the ring X ^u is a thiophene ring group or a furan ring group.

(6) The photoelectric conversion element according to any one of (1), wherein, ^Lu is a single bond, q is 0, and ^Ru is an amine group, an alkylamino group or an arylamine group.

The photoelectric conversion element according to any one of (1) to (6) wherein the ring A is a pyridine ring.

The photoelectric conversion element according to any one of (1) to (7), wherein LA is represented by the formula (AL-1).

The photoelectric conversion element according to any one of (1) to (8), wherein the semiconductor fine particles further carry a co-adsorbent having one or more acidic groups.

(10) The photoelectric conversion element according to (9), wherein the co-adsorbent is represented by the following formula (CA):

In the formula, R ^A1 represents a substituent having an acidic group. R ^A2 represents a substituent. nA represents an integer of 0 or more.

(11) A dye-sensitized solar cell comprising the photoelectric conversion element according to any one of (1) to (10).

(12) A metal complex dye represented by the following formula (I): M(LD)(LA)(Z). (CI) Formula (I)

In the formula (I), M represents a metal ion.

LD represents a bidentate ligand represented by the following formula (DL-1).

LA represents a tridentate ligand represented by the following formula (AL-1) or formula (AL-2).

Z represents a single tooth ligand.

CI represents the counter ion necessary to neutralize the charge.

[Chemical 5]

In the formula (DL-1), the ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring. Y ¹ represents a carbon atom or a nitrogen atom, and ring C1 represents a monocyclic or condensed ring aryl ring or heteroaryl ring which is coordinated to M by a carbo anion. R ^A is a group represented by the following formula (U). R ^B represents a substituent. R ^C represents a halogen atom, an alkyl group, a cycloalkyl group, a decyl group, an alkylsulfinylene group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group or a nitro group. A1 represents an integer of 1 to 4, a2 represents an integer of 0 to 3, and a3 represents an integer of 0 or more. In the case where a plurality of R ^A , R ^B and R ^C are respectively present, these may be the same or different.

In the formula (U), L ^u represents a single bond, a vinyl group or an ethynyl group. The ring X ^u represents an extended aryl group or a heteroaryl group, and q represents an integer of 0 to 2. R ^u represents a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group. Wherein, in the case where the ring X ^u is an extended aryl group, R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group. Nu represents an integer of 1 to 4. When nu is 2 or more, a plurality of R ^u may be the same or different, or may be bonded to each other to form a ring.

In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ each independently represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which any of these protons are dissociated. . R ^AL represents a substituent, and b1 represents an integer of 0-4.

(13) A dye solution obtained by dissolving the metal complex dye according to (12).

(14) The pigment solution according to the above aspect, wherein the organic solvent contains 0.001% by mass to 0.1% by mass of the metal complex dye, and the water content is 0.1% by mass or less.

(15) The dye solution according to (13) or (14), wherein the dye solution further contains a co-adsorbent.

(16) The dye solution according to (15), wherein the co-adsorbent is represented by the following formula (CA):

In the formula, R ^A1 represents a substituent having an acidic group. R ^A2 represents a substituent. nA represents an integer of 0 or more.

(17) A dye-adsorbing electrode for a dye-sensitized solar cell, which is obtained by applying the dye solution according to any one of (13) to (16) to a conductive support to which semiconductor fine particles are provided. The composition is obtained by curing the composition after coating as a photoreceptor layer.

(18) A method of producing a dye-sensitized solar cell, which comprises assembling each material of the dye-adsorbing electrode for a dye-sensitized solar cell according to (17), an electrolyte, and a counter electrode.

In the present specification, the numerical range expressed by "~" indicates a range including the numerical values described before and after the lower limit and the upper limit.

In the present specification, unless otherwise specified, the carbon-carbon double bond may be any of the E-type and the Z-type in the molecule, and may be a mixture of these. a substituent or a linking group represented by a specific symbol, a ligand, etc. When a plurality of substituents (hereinafter referred to as a substituent or the like) are present, or when a plurality of substituents or the like are specified at the same time or in a single place, unless otherwise specified, the respective substituents or the like may be the same or different. The same applies to the regulation of the number of substituents and the like. Further, when a plurality of substituents or the like are in close proximity (particularly adjacent), unless otherwise specified, the substituents may be bonded to each other to form a ring. Further, a ring (for example, an alicyclic ring, an aromatic ring or a heterocyclic ring) may be further condensed to form a condensed ring.

In the present invention, each substituent may be further substituted with a substituent unless otherwise specified.

According to the present invention, it is possible to provide a photoelectric conversion element, a dye-sensitized solar cell, and a metal-containing complex which are improved in durability in addition to improvement in photoelectric conversion efficiency, and which can stably maintain these properties even if they are repeatedly manufactured. A pigment solution, a dye adsorption electrode, and a method of producing a dye-sensitized solar cell.

1‧‧‧Electrical support

2‧‧‧Photoreceptor layer

3‧‧‧ Charge Transfer Body Layer

4, CE‧‧‧ relative electrode

5‧‧‧Photoelectrode

6‧‧‧ Circuitry

10‧‧‧ photoelectric conversion components

20‧‧‧Pigment sensitized solar cells

21‧‧‧ Pigment (metal complex pigment)

22‧‧‧Semiconductor particles

40‧‧‧Photoelectrode

41‧‧‧Transparent electrode

42‧‧‧Semiconductor electrodes

43‧‧‧Transparent conductive film

44‧‧‧Substrate

45‧‧‧Semiconductor layer

46‧‧‧Light scattering layer

100‧‧‧System for the use of dye-sensitized solar cells

E‧‧‧ Electrolytes

M‧‧‧Action Agency

S‧‧‧ spacers

Fig. 1 is a cross-sectional view schematically showing an embodiment of a photoelectric conversion element according to the present invention, including an enlarged view of a circular portion in a layer.

Fig. 2 is a cross-sectional view schematically showing a dye-sensitized solar cell according to another embodiment of the photoelectric conversion element of the present invention.

Figure 3 is a graph showing the visible absorption spectrum of the metal complex dye A-29 synthesized in the examples of the present invention in a DMF solution.

<<Photoelectric conversion element and dye-sensitized solar cell>>

As shown in FIG. 1, the photoelectric conversion element of the present invention includes, for example, a conductive support 1 and a photoreceptor layer 2 including semiconductor fine particles 22 sensitized by a dye (metal complex dye) 21 as a hole transport. The charge transfer body layer 3 of the layer and the opposite electrode 4. The conductive support 1 provided with the photoreceptor layer 2 functions as a working electrode in the photoelectric conversion element 10 . In the present embodiment, the photoelectric conversion element 10 is shown as a system 100 using a dye-sensitized solar cell, and the dye-sensitized solar cell can be used in a battery application in which an operation mechanism M (electric motor) is operated by an external circuit 6. use.

In the present embodiment, the light receiving electrode 5 includes the conductive support 1 and the photoreceptor layer 2 including the semiconductor fine particles 22 to which the dye (metal complex dye) 21 is adsorbed. The photoreceptor layer 2 is designed according to the purpose, and may be a single layer structure or a multilayer structure. The pigment (metal complex dye) 21 in one layer of the photoreceptor layer may be one type or a mixture of a plurality of types, and at least one of them may be a metal complex dye of the present invention to be described later. The light incident on the photoreceptor layer 2 excites the dye (metal complex dye) 21. The excited dye has electrons having high energy, and the electrons are transferred from the dye (metal complex dye) 21 to the conduction band of the semiconductor fine particles 22, and further reach the conductive support 1 by diffusion. At this time, the dye (metal complex dye) 21 becomes an oxidant, and the electrons on the electrode are returned to the oxidized body in which the dye (metal complex dye) 21 is present via the counter electrode 4 while being operated by the external circuit 6. The photoreceptor layer 2 of the electrolyte functions as a solar cell.

In the present invention, as for the material used in the photoelectric conversion element or the dye-sensitized solar cell and the method for producing each member, if such a material and each member are used For example, U.S. Patent No. 4,927,721, U.S. Patent No. 4,684,537, U.S. Patent No. 5,084,365, U.S. Patent No. 5,350,644, U.S. Patent No. 5,463,057, U.S. Patent No. 5,525,440 The specification, Japanese Patent Laid-Open No. Hei 7-249790, Japanese Patent Laid-Open No. Hei. No. 2004-220974, and Japanese Patent Laid-Open No. Hei No. 2008-135197.

Hereinafter, the main components will be briefly described.

<Photoreceptor layer>

The photoreceptor layer is a layer containing an electrolyte described later and including semiconductor fine particles carrying a sensitizing dye (the sensitizing dye includes the metal complex dye of the present invention described below).

<<Metal complex pigment>>

The metal complex dye of the present invention is represented by the following formula (I).

M(LD)(LA)(Z). (CI) Formula (I)

In the formula (I), M represents a metal ion.

LD represents a bidentate ligand represented by the following formula (DL-1).

LA represents a tridentate ligand represented by the following formula (AL-1) or formula (AL-2).

Z represents a single tooth ligand.

CI represents the counter ion necessary to neutralize the charge.

[Chemistry 9]

In the formula (DL-1), the ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring. Y ¹ represents a carbon atom or a nitrogen atom, and ring C1 represents a monocyclic or condensed ring aryl ring or heteroaryl ring which is coordinated to M by a carbo anion. R ^A is a group represented by the following formula (U). R ^B represents a substituent. R ^C represents a halogen atom, an alkyl group, a cycloalkyl group, a decyl group, an alkylsulfinylene group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group or a nitro group. A1 represents an integer of 1 to 4, a2 represents an integer of 0 to 3, and a3 represents an integer of 0 or more. In the case where a plurality of R ^A , R ^B and R ^C are respectively present, these may be the same or different.

In the formula (U), L ^u represents a single bond, a vinyl group or an ethynyl group. The ring X ^u represents an extended aryl group or a heteroaryl group, and q represents an integer of 0 to 2. R ^u represents a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group. Wherein, in the case where the ring X ^u is an extended aryl group, R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group. Nu represents an integer of 1 to 4. When nu is 2 or more, a plurality of R ^u may be the same or different, or may be bonded to each other to form a ring.

In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ each independently represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which any of these protons are dissociated. . R ^AL represents a substituent, and b1 represents an integer of 0-4.

- metal ion M-

M represents a central metal ion of the metal complex dye, and examples thereof include ions of a metal atom of a group 6 to 12 of the long period table, and more preferably Ru, Fe, Os, Cu, W, Cr, Mo, Ni, Pd. Further, ions of Pt, Co, Ir, Rh, Re, Mn or Zn are further more preferably Fe ²⁺ , Ru ²⁺ or Os ²⁺ , and most preferably Ru ²⁺ .

- Ligand LD-

In the present invention, as the ligand LD, a ligand represented by the above formula (DL-1) is used.

In the present invention, according to the formula (I) of the present invention, it is known that the ligand LD is combined with the ligand LA and a compound having a specific ligand structure to be coordinated to the metal ion M, and the ligand LA is A ligand having an acidic group adsorbed on the surface of the semiconductor fine particles, and the ligand LD is a ligand which is not supposed to be adsorbed on the surface of the semiconductor fine particles.

In the present invention, in order to increase the adsorption force of the ligand LA on the surface of the semiconductor fine particles, it is considered that the electron effect of the ligand LD is effective, that is, for the acidic group of the ligand LA, not via coordination The bulk LA is adjusted by the ligand LD, and a bidentate ligand having a higher π electron acceptability than the conventional pyridine-based ligand is used. Further, it is considered to be effective in changing the ring or suppressing the association of the dye due to the modification of the substituent and improving the coordination force.

For this purpose, the effective ligand LD is a cation in which a nitrogen-containing heterocyclic ring selected from a pyridine ring, a pyrimidine ring and a pyridazine ring is coordinated with a carbon anion, which is coordinated with respect to the metal ion M, with respect to the metal ion M. a bidentate ligand in which a base ring or a heteroaryl ring is bonded, and at least a nitrogen-containing heterocyclic ring selected from a pyridine ring, a pyrimidine ring, and a pyridazine ring, which is coordinated with respect to the metal ion M, with respect to the metal ion M The above formula (DL-1) having a specific substituent is useful.

Hereinafter, the ligand represented by the formula (DL-1) will be described in detail.

Ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring, preferably a pyridine ring. Further, at least one R ^A is substituted on the ring A.

R ^A represents the above formula (U), a1 represents an integer of 1 to 4, and a1 is preferably 1 or 2, more preferably 1.

Hereinafter, the basis represented by the formula (U) will be described in detail.

L ^u represents a single bond, a vinyl group or an ethynyl group, and preferably a single bond or a vinyl group.

The aryl ring in the aryl group of the ring X ^u may, for example, be an aryl ring in the ring C1, preferably a benzene ring.

The heteroaryl ring in the heteroaryl group of the ring X ^u may, for example, be a heteroaryl ring in the ring C1, preferably a thiophene ring or a furan ring, more preferably a thiophene ring or a condensed ring thiophene ring.

The ring condensed to the thiophene ring is preferably a benzene ring, a ring formed by stretching an ethyldioxy group, a thiophene ring or a combination thereof.

The condensed ring thiophene ring, that is, the divalent condensed ring thiophene ring is preferably the following group.

Further, each of the above rings may have a substituent, and examples of the substituent include a substituent T to be described later. The substituent is preferably an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group or an amine group.

q represents an integer of 0 to 2, preferably 0 or 1, more preferably 0.

R ^u represents a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group, and the ring X ^u is a aryl group. In the case of a hetero or aryl group, R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group.

The linear or branched alkyl group preferably has a carbon number of from 1 to 20, more preferably a carbon number of from 3 to 18, still more preferably a carbon number of from 3 to 14, and examples thereof include a methyl group and an ethyl group. , propyl, isopropyl, tert-butyl, pentyl, hexyl, heptyl, octyl, isooctyl, 2-ethylhexyl, decyl, tridecyl, etc., preferably propyl, Pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, decyl, tridecyl.

The alkoxy group preferably has a carbon number of from 1 to 20, more preferably a carbon number of from 6 to 8, more preferably a carbon number of 6, and examples thereof include a methoxy group, an ethoxy group, and a hexyloxy group. Further, 2-ethylpentyloxy, octyloxy, 2-ethylhexyloxy and the like are preferred, and hexyloxy, 2-ethylpentyloxy, octyloxy and 2-ethylhexyloxy are preferred.

The above alkylthio group preferably has a carbon number of from 1 to 20, more preferably a carbon number of from 2 to 8, more preferably a carbon number of 6, and examples thereof include a methylthio group, an ethylthio group, and a propylthio group. The isopropylthio group, the butylthio group, the hexylthio group, the octylthio group, the 2-ethylhexylthio group and the like are preferably a hexylthio group, an octylthio group or a 2-ethylhexylthio group.

The alkynyl group is preferably a carbon number of 2 to 20, more preferably a carbon number of 3 to 13, more preferably a carbon number of 7, and examples thereof include a 1-propynyl group and a 2-propynyl group. 2-butynyl, 1-heptynyl, 1-octynyl and the like.

The above alkenyl group preferably has a carbon number of 2 to 20, more preferably a carbon number of 3 to 13, more preferably a carbon number of 7, and examples thereof include a vinyl group, an allyl group, and a 2-propenyl group. 2-butenyl, 1-heptenyl, oleyl, and the like.

The above fluorenyloxy group is preferably a decyloxy group having an alkyl group or an aryl group substituted on the fluorenylalkyl group, and the alkyl group to be substituted preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms. Further better is 3~8. The carbon number of the substituted aryl group is preferably from 6 to 20, more preferably from 6 to 12. As the decyloxy group, among them, a trialkyl decyloxy group is preferred.

The carbon number of the decyloxy group is preferably from 3 to 60, more preferably from 3 to 40, still more preferably from 8 to 20. For example, trimethyl decyloxy, triethyl decyloxy, tributyl decyloxy, dimethyl benzyl fluorenyloxy, dimethyl phenyl fluorenyloxy, benzyl Phenyl fluorenyloxy and the like.

In the case where L ^u is a single bond and q is 0, R ^{u is} preferably an amine group, an alkylamino group or an arylamine group.

Preferred from the viewpoint of R ^u , particularly long-wavelength self-absorption, an alkyl group or an arylamine group, more preferably an arylamine group, of an amine group, an alkylamino group or an arylamine group. base. The arylamine group may, for example, be an N-alkyl-N-arylamino group or a diarylamine group, preferably a diarylamine group.

R ^{u is} preferably a group represented by the following formula (SA).

In the formula, R ^uA1 and R ^uA2 each independently represent an alkyl group or an aryl group. R ^uA1 and R ^uA2 may also be bonded to each other to form a ring. It is preferred that any of R ^uA1 and R ^uA2 is an aryl group, and it is more preferred that both ^RuA1 and ^RuA2 are aryl groups.

Here, the group of the ring formed by bonding R ^uA1 and R ^{uA2 to} each other is preferably a 5-membered ring or a 6-membered ring carbocyclic group or heterocyclic group.

Further, the group of the ring formed by bonding R ^uA1 and R ^{uA2 to} each other is more preferably the following group.

Here, R ^uA3 and R ^uA4 each independently represent an alkyl group.

The alkyl group in R ^uA3 and R ^uA4 preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably 1 to 8 carbon atoms, and particularly preferably a methyl group.

In the formula (U), a ring in which a plurality of R ^u are bonded to each other is preferably a 5-membered ring or a 6-membered ring carbocyclic or heterocyclic ring. The rings may also be aromatic rings. Preferred examples of the ring include a ring formed of an ethylenedioxy group, an aryl ring and a heteroaryl ring. The aryl ring and the heteroaryl ring are preferably an aryl ring exemplified in the ring C1 described later. , heteroaryl ring.

In the group represented by the above formula (U), it is preferred that R ^u is bonded to the ortho or meta position with respect to the position of the atom of the ring X ^u to which L ^u is bonded.

As the group represented by the above formula (U), preferred is a case where L ^u is a single bond, q is 0, R ^u is an amine group, an alkylamino group or an arylamine group, and further preferably a ring. A is the case of a pyridine ring.

In the formula (DL-1), Y ¹ represents a carbon atom or a nitrogen atom.

Ring C1 represents a monocyclic or condensed aryl or heteroaryl ring coordinated by a carbanion. Here, the bond of Y ¹ and the carbon anion may be a single bond or a double bond.

The aryl ring in the ring C1 may, for example, be a benzene ring or a naphthalene ring, and is preferably a benzene ring.

As the heteroaryl ring in the ring C1, the ring constitutes a hetero atom, preferably an oxygen atom, a sulfur atom or a nitrogen atom, or a plurality of combinations. Further, in the case where the ring constituent atom contains a nitrogen atom, when the nitrogen atom is adjacent to Y ¹ , a nitrogen atom having a substituent is preferable, and when the nitrogen atom is not adjacent to Y ¹ , The nitrogen atom may be substituted with a hydrogen atom, or may be =N-, preferably a nitrogen atom having a substituent. Specifically, Rx is a substituent such as -N(Rx)-, and the substituent T is a substituent T to be described later, and an alkyl group or an aryl group is preferred, and an alkyl group is more preferred.

The heteroaryl ring in ring C1 is preferably a 5-membered ring or a 6-membered ring, more preferably a 5-membered ring.

The ring C1 may also be a condensed ring, and in the case of a condensed ring, a fused ring having an aryl ring, an alicyclic ring, and a heterocyclic ring containing a heteroaryl ring may be contained on the above aryl monocyclic or heteroaryl monocyclic ring.

In the case of an aryl ring, a naphthalene ring is preferred, and a ring is formed on the benzene ring by stretching an ethyldioxy group.

In the case of a heterocyclic ring, the 5-membered ring may be a furan ring, a thiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, a triazole ring, an oxazole ring, an isoxazole ring, or a thiophene ring. The azole ring, the isothiazole ring, and the furazan ring may, in the case of a condensed ring, a ring in which a ring is condensed with a benzene ring, such as a benzofuran ring, a benzothiophene ring, an anthracene ring, Benzimidazole ring and the like. Further, a ring which forms a condensed ring by stretching an ethyl dioxy group is also preferable.

In the case of a monocyclic ring, the 6-membered ring may, for example, be a pyridine ring, a pyrazine ring, a pyrimidine ring or a pyridazine ring, and the condensed ring may be a condensed ring of the ring and the benzene ring.

In the present invention, the ring C1 is preferably a thiophene ring, a furan ring, a pyrrole ring or a benzene ring.

The ring C1 is preferably a ring represented by the following formula (C1-a) to formula (C1-e).

Here, R ^C and a ₃ have the same meanings as R ^C and a3 in the above formula (DL-1), and the preferred range is also the same. Further, a ₃ in each formula is preferably an integer of 0 to 2 in the formula (C1-a) and the formula (C1-b), and preferably an integer of 0 to 3 in the formula (C1-c). Preferably, in the formula (C1-d), an integer of 0 to 2 is preferable, and in the formula (C1-e), an integer of 0 to 4 is preferable.

Rx is the same as Rx described above, and represents a substituent. The substituent may be a substituent T to be described later, preferably an alkyl group or an aryl group, and more preferably an alkyl group.

R ^B in the formula (DL-1) represents a substituent, and examples of the substituent include a substituent T to be described later. Further, when a2 is 2 or more, a plurality of R ^{Bs present} may be the same or different from each other, and when a3 is 2 or more, a plurality of R ^{Cs present} may be the same or different.

The substituent in R ^B is preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, The amine group and the halogen atom are more preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an alkylthio group or an arylthio group.

A2 is preferably 0 or 1, and particularly preferably 0.

R ^C represents an alkyl group, a cycloalkyl group, a halogen atom, a fluorenyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group, a nitro group, preferably It is an alkyl group or a halogen atom.

The above alkyl group is preferably an unsubstituted alkyl group, an alkyl group substituted by a halogen atom, preferably a perhaloalkyl group, more preferably a perfluoroalkyl group, and particularly preferably a trifluoromethyl group. The halogen atom is preferably a fluorine atom. Further, the carbon number of the alkyl group is preferably from 1 to 20, more preferably from 1 to 12, still more preferably from 1 to 8, more preferably 1 or 2, and particularly preferably 1.

The cycloalkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 16 carbon atoms, still more preferably 3 to 12 carbon atoms, and examples thereof include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, and a 3-methyl group. Cyclopentyl, 4-methylcyclohexyl, 4-ethylcyclohexyl, 3,5-dimethylcyclohexyl and the like.

The above mercapto group includes a mercapto group, an alkylcarbonyl group, an alkenylcarbonyl group, a cycloalkylcarbonyl group, an arylcarbonyl group or a heterocyclic carbonyl group, and the mercapto group preferably has a carbon number of from 1 to 20, more preferably 1~16, further better is 1~12. For example, a mercapto group, an ethyl fluorenyl group, a propyl fluorenyl group, a butyl fluorenyl group, a trimethyl ethane group, a cyclohexyl carbonyl group, a benzamidine group, an acryl fluorenyl group, a methacryl fluorenyl group, a benzamidine group, a naphthyl group may be mentioned. Mercapto, pyridylcarbonyl and the like.

The alkylsulfinyl group and the arylsulfinyl group have a carbon number of preferably 1 to 20, more preferably 1 to 16, still more preferably 1 to 8, and examples thereof include methylsulfin Ethyl, sulfinyl, propylsulfinyl, butylsulfinyl, pentylsulfinyl, hexylsulfinyl, phenylsulfinyl, 1-naphthylsulfinium A group, a 2-naphthylsulfinyl group, a p-toluenesulfinyl group, and the like.

The alkylsulfonyl group and the arylsulfonyl group preferably have 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, still more preferably 1 to 8 carbon atoms, and examples thereof include methylsulfonyl group and B. A sulfonyl group, a cyclohexylsulfonyl group, a phenylsulfonyl group, a 1-naphthylsulfonyl group, a 2-naphthylsulfonyl group, a p-toluenesulfonyl group, and the like.

A3 is preferably an integer of 0 to 2, more preferably 1 or 2.

Further, in the formula (DL-1), from the viewpoint of the carbon number of the substituent in R ^A , R ^B and R ^C , the carbon number is preferably from 6 to 40, more preferably from 6 to 36, furthermore. The best is 6~24, the best is 8~24. Therefore, it is preferred that at least one of R ^A , R ^B and R ^C is the carbon number in the preferred range. Particularly preferably, in R ^A , R ^u is the above carbon number.

Further, the total number of carbon atoms of R ^A , R ^B and R ^C is preferably from 6 to 50, more preferably from 8 to 30, still more preferably from 8 to 25.

At least one of R ^A , R ^B and R ^C is preferably a group containing a heteroaryl ring, of which a group containing a thiophene ring is preferred.

Wherein R ^{u in} R ^A is preferably an amine group, an alkylamino group or an arylamine group, particularly preferably an arylamine group, and in this case, it is preferred that ^Lu is a single bond. And q is 0.

Specific examples of the ligand represented by the formula (DL-1) of the present invention are shown below, but the present invention is not limited to these specific examples.

[化17]

[化18]

[Chemistry 19]

-ligand LA-

In the present invention, the ligand LA is a ligand represented by the above formula (AL-1) or formula (AL-2).

In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which these protons are dissociated.

Here, the group in which the proton is dissociated is, for example, the above anion or a salt thereof, and an anion is preferred in order to coordinate with the metal ion M. For example, -CO ₂ ^- , -SO ₃ ^- , -PO ₃ H ^- , -PO ₃ ^2- .

In the present invention, a group in which -CO ₂ H or a proton thereof is dissociated is preferred.

In the formula (AL-2), R ^AL represents a substituent, and examples of the substituent include a substituent T to be described later.

R ^{AL is} preferably an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aromatic heterocyclic group or a substituted amino group. Here, the substituted amine group is preferably an alkylsulfonylamino group, and the carbon number of the alkyl group is not particularly limited, and is preferably 1 to 6. Further, the aromatic heterocyclic group is preferably a thienyl group or a furyl group, more preferably a thienyl group.

B1 represents an integer of 0 to 4, preferably 0 or 1, more preferably 1.

Hereinafter, specific examples of the ligand LA will be described, and the present invention is not limited thereto.

Further, in the following structure, Anc ¹ to Anc ³ are expressed in a state in which dissociable protons are not dissociated, and these protons can also be dissociated to become tetrabutylammonium ions ( ⁺ NBu ₄ ) or triethylammonium. A salt forming an ion pair such as an ion ( ⁺ NHEt ₃ ), a lithium ion, a sodium ion, a potassium ion, or a cesium ion.

Specific examples of the ligand represented by the formula (AL-1)

[Chemistry 20]

Specific examples of the ligand represented by the formula (AL-2)

-ligand Z-

Z represents a single tooth ligand. Z may, for example, be selected from the group consisting of decyloxy, sulfonylthio, thiodecyloxy, thiosulfonylthio, decylaminooxy, thiocarbamate, dithio Carbamate group, thiocarbonate group, dithiocarbonate group, trithiocarbonate group, mercapto group, thiocyanate group, isothiocyanate group, cyanate group, isocyanate group a single tooth coordinated by a group consisting of a selenate group, an isoselenoate group, an isostealenate group, a cyano group, an alkylthio group, an arylthio group, an alkoxy group, and an aryloxy group a ligand, or a monodentate ligand selected from the group consisting of a halogen atom, a phosphine ligand, a carbonyl group, a dialkyl ketone, a carbonamide, a thiocarbaguanyl group, and a thiourea . Z is preferably an isothiocyanate group, an isoselocyanate group, an isocyanate group, a halogen atom or a cyano group. Further, when the ligand Z includes an alkyl moiety, an alkenyl moiety, an alkynyl moiety, an alkylene moiety, or the like, these may be linear or branched, and may be substituted or unsubstituted. . Further, in the case of containing an aryl moiety, a heterocyclic moiety, a cycloalkyl moiety or the like, these may be substituted or unsubstituted, and may be monocyclic or condensed.

- Charge Neutralization Pair Ion CI-

CI represents a counter ion in the case where ions are necessary to neutralize the charge. In general, a dye is a cation or an anion, or whether a substantial ionic charge is a metal, a ligand, and a substituent depending on the metal complex dye.

Since the substituent has a dissociable group or the like, the metal complex dye can also be dissociated to have a negative charge. In this case, the charge of the entire metal complex dye becomes electrically neutral due to CI.

In the case of a counter ion having a positive ion CI, for example, the ion CI is Inorganic or organic ammonium ions (eg, tetraalkylammonium ions, pyridinium ions, etc.), cesium ions (eg, tetraalkylphosphonium ions, alkyltriphenylphosphonium ions, etc.), alkali metal ions, metal complex ions, or Proton. The positive counter ion is preferably an inorganic or organic ammonium ion (triethylammonium ion, tetrabutylammonium ion, etc.) or a proton.

In the case of a counter ion having a negative ion CI, for example, the counter ion may be an inorganic anion or an organic anion. For example, hydroxide ions, halogen anions (for example, fluoride ions, chloride ions, bromide ions, iodide ions, etc.), substituted or unsubstituted alkyl carboxylate ions (acetate ion, trifluoroacetic acid) may be mentioned. Root ion, etc.), substituted or unsubstituted aryl carboxylate ion (benzoate ion, etc.), substituted or unsubstituted alkylsulfonate ion (methanesulfonate ion, triflate ion, etc.) ), substituted or unsubstituted aryl sulfonate ion (eg p-toluenesulfonate ion, p-chlorobenzenesulfonate ion, etc.), aryl disulfonate ion (eg 1,3-benzenedisulfonate ion, 1 , 5-naphthalene disulfonate ion, 2,6-naphthalene disulfonate ion, etc.), alkyl sulfate ion (such as methyl sulfate ion, etc.), sulfate ion, thiocyanate ion, perchlorate ion, Tetrafluoroborate ion, hexafluorophosphate ion, or picrate ion. Further, the charge equalization ion may be an ionic polymer or another dye having an opposite charge to the dye, and a metal counter ion such as bis(benzene-1,2-dithiol)nickel(III) may be used. ]. The negative counter ion is preferably a halogen anion, a substituted or unsubstituted alkyl carboxylate ion, a substituted or unsubstituted alkylsulfonate ion, a substituted or unsubstituted arylsulfonate ion, An aryl disulfonate ion, a perchlorate ion, a hexafluorophosphate ion, more preferably a halogen anion or a hexafluorophosphate ion.

Specific examples of the metal complex dye of the present invention are shown below, but the present invention is not limited thereto. Further, in the following structure, the CI mark in the formula (I) is a proton, and may be a tetrabutylammonium ion ( ⁺ NBu ₄ ) or a sodium ion.

[化23]

[Chem. 24]

[化25]

[Chem. 26]

[化27]

[化28]

[化29]

The metal complex dye of the present invention can be obtained by the Japanese Patent Laid-Open Publication No. 2009-51999, "Chemistry-A European Journal", 17 (39), 10871~10878 (2011), "Applied Chemistry (Angewandte Chemie), 84, 824~826 (1972), "Dalton Transactions", 5, 770~772 (2009), Japanese Patent Laid-Open No. 2001-291534, or The method is a standard method and is easily synthesized by a method based on the method described in "Angew. Chem. Int. Ed.", 50, 2054 to 2058 (2011).

The maximum absorption wavelength of the metal complex dye of the present invention in the solution is preferably in the range of 300 nm to 1000 nm, more preferably in the range of 350 nm to 950 nm, and particularly preferably in the range of 370 nm to 900 nm.

In the present invention, the metal complex dye of the present invention may be used in combination with other pigments.

The pigment to be used in combination is a Ru complex dye described in Japanese Patent Laid-Open Publication No. Hei 7-500630 (especially in the fifth row from the lower left column on page 5 to the seventh row in the upper right column on page 7 by the example 1 ~ The pigment synthesized in Example 19), and the Ru complex dye described in Japanese Patent Laid-Open Publication No. 2002-512729 (especially on page 20, the third row to the 29th page, in line 23, by Example 1~ The pigment which is synthesized in the case of the above-mentioned Patent No. 2001-59062, which is described in JP-A-2001-59062 (especially the pigment described in Paragraph No. 0087 to Paragraph No. 0104), Japanese Patent Laid-Open No. 2001-6760 Ru complex pigments described in the bulletin (especially paragraph number In the case of the pigments described in JP-A No. 2001-253894, the pigments described in JP-A-2001-253894 (especially the pigments described in Paragraph No. 0009 to Paragraph No. 0010), and Japanese Patent Publications The Ru complex dye (hereinafter, the pigment described in Paragraph No. 0005) and the Ru complex dye described in the specification of International Publication No. 2007/91525 (especially [0067] The pigments described in the Japanese Patent Laid-Open Publication No. 2001-291534 (especially the pigments described in Paragraph No. 0120 to Paragraph No. 0144), Japanese Patent Laid-Open No. 2012-012570 The Ru complex dye (hereinafter, the pigment described in Paragraph No. 0095 to Paragraph No. 0103) and the Ru complex dye described in the specification of International Publication No. 2013/47615 (especially [0078] The squaraine cyanine dye described in Japanese Laid-Open Patent Publication No. Hei 11-214730 (especially the pigment described in paragraph No. 0036 to paragraph No. 0047), Japanese Patent Noted in JP-A-2012-144688 The squaraine cyanine pigment (especially the pigments described in paragraph number 0039 to paragraph 0046 and paragraph number 0054 to paragraph number 0060), and the squaraine cyanine described in JP-A-2012-84503 The pigment (especially the pigment described in paragraph number 0066 to paragraph number 0076), and the organic dye described in JP-A-2004-063274 (especially the pigment described in paragraph number 0017 to paragraph number 0021) The organic coloring matter (especially the pigment described in Paragraph No. 0021 to Paragraph No. 0028) and the organic coloring matter described in Japanese Patent Laid-Open Publication No. 2007-287694, Is a paragraph The organic coloring matter described in Japanese Patent Laid-Open Publication No. 2008-71648 (especially the coloring matter described in Paragraph No. 0030 to Paragraph No. 0034), International Publication No. 2007/ The organic dye described in the specification No. 119525 (particularly, the pigment described in [0024]), "Angew. Chem. Int. Ed.", 49, 1 to 5 (2010), etc. The porphyrin dye described in "Angew. Chem. Int. Ed.", 46, 8358 (2007) and the like.

The pigment to be used in combination is preferably a Ru complex dye, a squaraine cyanine dye, or an organic dye.

When the metal complex dye of the present invention is used in combination with other dyes, the ratio of the mass of the metal complex dye of the present invention to the mass of the other dye is preferably 95/5 to 10/90, more preferably It is 95/5~50/50, further better is 95/5~60/40, especially good is 95/5~65/35, the best is 95/5~70/30.

- Conductive support -

The conductive support is preferably a glass or plastic support having a conductive body or a conductive film layer on the surface as a metal. For example, the transparent polymer film described in Paragraph No. 0153 of JP-A-2001-291534 is exemplified. In addition to the glass and the plastic, a ceramic (Japanese Patent Laid-Open Publication No. 2005-135902) and a conductive resin (Japanese Patent Laid-Open Publication No. 2001-160425) can be used. The surface of the conductive support may be subjected to a light management function, for example, an anti-reflection of an oxide film having a high refractive index and a low refractive index as described in Japanese Laid-Open Patent Publication No. 2003-123859. The film may have a light guiding function as described in Japanese Laid-Open Patent Publication No. 2002-260746.

The thickness of the conductive film layer is preferably from 0.01 μm to 30 μm, more preferably from 0.03 μm to 25 μm, and particularly preferably from 0.05 μm to 20 μm.

The conductive support is preferably substantially transparent. The term "substantially transparent" means that the transmittance of light is 10% or more, preferably 50% or more, and particularly preferably 80% or more. The transparent conductive support is preferably one in which a conductive metal oxide is coated on glass or plastic. The metal oxide is preferably a tin oxide, and particularly preferably an indium-tin oxide or a fluorine-doped oxide. The amount of the conductive metal oxide applied at this time is preferably from 0.1 g to 100 g per 1 m ^{2 of the} glass or plastic support. In the case of using a transparent conductive support, it is preferred that light is incident from the side of the support.

-Semiconductor microparticles -

The semiconductor fine particles are preferably metal chalcogenides (e.g., oxides, sulfides, selenides, etc.) or perovskite fine particles. The metal chalcogenide is preferably an oxide of titanium, tin, zinc, tungsten, zirconium, hafnium, yttrium, indium, lanthanum, cerium, lanthanum, vanadium, niobium or tantalum, cadmium sulfide, cadmium selenide or the like. The perovskite is preferably exemplified by barium titanate, calcium titanate or the like. Particularly preferred among these are titanium oxide (titanium dioxide), zinc oxide, tin oxide, and tungsten oxide.

The crystal structure of titanium dioxide may be an anatase type, a brookite type, or a rutile type, and an anatase type or a brookite type is preferable. A titanium dioxide nanotube, a titanium dioxide nanowire, or a nanorod may be mixed in the titanium dioxide fine particles or used as a semiconductor electrode.

The particle diameter of the semiconductor fine particles is preferably 0.001 μm to 1 μm for the primary particles and 0.01 μm to 100 μm for the average particle diameter (the diameter when the projected area is converted into a circle). Examples of the method of coating the semiconductor fine particles on the conductive support include a wet method, a dry method, and other methods.

It is preferable to form a short-circuit prevention layer between the transparent conductive film and the semiconductor layer (photoreceptor layer) in order to prevent reverse current generated by direct contact between the electrolyte and the electrode. In order to prevent contact of the photoelectrode with the opposite electrode, it is preferred to use a spacer or a spacer. The semiconductor fine particles preferably have a large surface area to facilitate adsorption of a large amount of the pigment. For example, in a state where the semiconductor fine particles are coated on the support, the surface area thereof is preferably 10 times or more, more preferably 100 times or more, with respect to the projected area. The upper limit is not particularly limited and is usually about 5,000 times. In general, the larger the thickness of the layer (photoreceptor layer) containing the semiconductor fine particles, the more the amount of the dye that can be carried per unit area is increased, so that the light absorption efficiency is increased, but the diffusion distance of the generated electrons is increased, Therefore, the loss due to charge recombination also becomes large. The preferred thickness of the photoreceptor layer as the semiconductor layer varies depending on the use of the device, and is typically 0.1 μm to 100 μm. When used as a dye-sensitized solar cell, it is preferably 1 μm to 50 μm, more preferably 3 μm to 30 μm. In order to adhere the particles to the support after the semiconductor fine particles are applied to the support, the firing may be performed at a temperature of 100 ° C to 800 ° C for 10 minutes to 10 hours. In the case where glass is used as the support, the film formation temperature is preferably 60 to 400 °C.

Further, the amount of the semiconductor fine particles applied per 1 m ^{2 of the} support is preferably 0.5 g to 500 g, more preferably 5 g to 100 g. The amount of the pigment to be used is preferably from 0.01 millimolar to 100 millimoles per 1 m ^{2 of the} support, more preferably from 0.1 millimolar to 50 millimolar, and particularly preferably 0.1. Millions of ears ~ 10 millimoles. In this case, it is preferred to use the metal complex dye of the present invention in an amount of 5 mol% or more. Further, the amount of adsorption of the dye to the semiconductor fine particles is preferably 0.001 mmol to 1 mmol, and more preferably 0.1 mmol to 0.5 mmol, relative to 1 g of the semiconductor fine particles. The sensitizing effect in the semiconductor fine particles is sufficiently obtained by setting the amount of the pigment.

In the case where the above-mentioned dye is a salt, the ion of the specific metal complex dye is not particularly limited, and examples thereof include an alkali metal ion or a quaternary ammonium ion.

After adsorbing the dye, the surface of the semiconductor fine particles can also be treated with an amine. Preferred examples of the amines include pyridines (for example, 4-tert-butylpyridine and polyvinylpyridine). These compounds can be used as they are in the liquid or in an organic solvent.

In the photoelectric conversion element (for example, the photoelectric conversion element 10) of the present invention and the dye-sensitized solar cell (for example, the dye-sensitized solar cell 20), at least the above-described metal complex dye of the present invention is used.

- Charge transfer body layer -

The charge transporting body layer used in the photoelectric conversion element of the present invention is a layer having a function of supplementing electrons to the oxidant of the dye, and is provided between the light receiving electrode (photoelectrode) and the counter electrode (opposing electrode). The charge transfer body layer contains an electrolyte. Examples of the electrolyte include a liquid electrolyte in which redox is dissolved in an organic solvent, and a liquid obtained by dissolving a redox pair in an organic solvent in a polymer matrix. A so-called gel electrolyte, a molten salt containing a redox couple, or the like. In order to improve the photoelectric conversion efficiency, a liquid electrolyte is preferred. The solvent of the liquid electrolyte is a nitrile compound, an ether compound, an ester compound or the like, preferably a nitrile compound, and particularly preferably acetonitrile or methoxypropionitrile.

Examples of the redox pair include iodine and iodide (preferably an iodide salt, an iodinated ionic liquid, more preferably lithium iodide, tetrabutylammonium iodide, tetrapropylammonium iodide, or iodide). Combination of propylidene imidazolium), alkyl viologen (eg, methyl viologen chloride, hexyl viologen bromide, benzyl viologen tetrafluoroborate) in combination with its reducing body, polyhydroxybenzene (eg, pair Combination of benzenediol, naphthalenediol, etc.) with its oxidant, combination of divalent and trivalent iron complexes (for example, a combination of red blood salt and yellow blood salt), bivalent and trivalent cobalt complex The combination and so on. Preferred among these are a combination of iodine and iodide or a combination of a divalent and trivalent cobalt complex.

Among them, the cobalt complex is preferably a complex represented by the following formula (CC).

Co(LL)ma(X)mb. CI type (CC)

In the formula (CC), LL represents a 2- or 3-dentate ligand. X represents a single tooth ligand. Ma represents an integer from 0 to 3. Mb represents an integer from 0 to 6. CI represents a counter ion in the case where ions are necessary to neutralize the charge.

CI can be cited as CI in the above formula (I).

LL is preferably a ligand represented by the following formula (LC).

[化30]

In the formula (LC), X ^LC1 and X ^LC3 each independently represent a carbon atom or a nitrogen atom. Here, in the case where X ^LC1 is a carbon atom, the bond of the N atom adjacent to X ^LC1 represents a double bond (X ^LC1 =N), and in the case where X ^LC3 is a carbon atom, the N atom adjacent to X ^LC3 The bond represents a double bond (X ^LC3 = N). In the case where X ^LC1 is a nitrogen atom, the bond of the N atom adjacent to X ^LC1 represents a single bond (X ^LC1 -N), and the X ^LC3 is a nitrogen atom. In the case, the bond of the N atom adjacent to X ^LC3 represents a single bond (X ^LC3 -N).

Z ^LC1 , Z ^LC2 and Z ^LC3 each independently represent a group of non-metal atoms necessary to form a 5-membered or 6-membered ring. Z ^LC1 , Z ^LC2 and Z ^LC3 may have a substituent or may be ring-closed to an adjacent ring via a substituent. The substituent T which will be described later can be mentioned as this substituent. q means 0 or 1. Further, in the case where q is 0, X ^LC3 is bonded to a hydrogen atom bonded to a carbon atom at a position of a 5-membered ring or a 6-membered ring formed by Z ^LC2 or formed by Z ^LC3 Substituents other than a cyclic group.

In the formula (CC), X is preferably a halide ion.

The ligand represented by the above formula (LC) is more preferably a ligand represented by the following formula (LC-1) to formula (LC-4).

[化31]

R ^LC1 to R ^LC11 each independently represent a substituent. Q1, q2, q6, and q7 each independently represent an integer of 0-4. Q3, q5, q10, and q11 each independently represent an integer of 0 to 3. Q4 represents an integer from 0 to 2.

In the formula (LC-1) to the formula (LC-4), examples of the substituent represented by R ^LC1 to R ^LC11 include an aliphatic group, an aromatic group, and a heterocyclic group. Specific examples of the substituent include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, and a heterocyclic group. Preferred examples thereof include an alkyl group (e.g., methyl, ethyl, n-butyl, n-hexyl, isobutyl, t-butyl, t-butyl, n-dodecyl, cyclohexyl, benzyl, etc.), An aryl group (e.g., phenyl, tolyl, naphthyl, etc.), an alkoxy group (e.g., methoxy, ethoxy, isopropoxy, butoxy, etc.), an alkylthio group (e.g., methylthio, n-butyl) Sulfhydryl, n-hexylthio, 2-ethylhexylthio, etc.), aryloxy (e.g., phenoxy, naphthyloxy, etc.), arylthio (e.g., phenylthio, naphthylthio, etc.), heterocyclic (e.g., 2-thienyl, 2-furyl, etc.).

Specific examples of the cobalt complex having a ligand represented by the formula (LC) include the following complexes.

In the case of using a combination of iodine and iodide as the electrolyte, it is preferred to further use an iodide salt of a nitrogen-containing aromatic cation of a 5-membered ring or a 6-membered ring.

The organic solvent for dissolving the redox couple is preferably an aprotic polar solvent (for example, acetonitrile, propyl carbonate, ethyl carbonate, dimethylformamide, dimethyl hydrazine, cyclobutyl hydrazine, 1, 3). - Dimethylimidazolidinone, 3-methyloxazolidinone, etc.). The polymer (polymer matrix) used in the matrix of the gel electrolyte may, for example, be polyacrylonitrile, polyvinylidene fluoride or the like. Examples of the molten salt include those obtained by mixing polyethylene oxide with other at least one lithium salt (for example, lithium acetate or lithium perchlorate) to impart fluidity at room temperature. This situation The amount of the polymer added is from 1% by mass to 50% by mass. Further, γ-butyrolactone may be contained in the electrolytic solution, whereby the diffusion efficiency of the iodide ions is increased, and the conversion efficiency is improved.

As an additive to the electrolyte, in addition to the above-mentioned 4-tert-butylpyridine, an aminopyridine-based compound, a benzimidazole-based compound, an aminotriazole-based compound, an aminothiazole-based compound, or an imidazole-based compound may be added. A compound, an aminotriazine-based compound, a urea derivative, a guanamine compound, a pyrimidine-based compound, and a nitrogen-free heterocyclic ring.

Further, in order to improve the photoelectric conversion efficiency, a method of controlling the moisture of the electrolytic solution may be employed. A preferred method of controlling the moisture may be a method of controlling the concentration or a method of coexisting the dehydrating agent. In order to reduce the toxicity of iodine, a clathrate of iodine and cyclodextrin may also be used, and a method of instantly replenishing water may also be used. Further, a cyclic ruthenium may be used, and an antioxidant, a hydrolysis inhibitor, a decomposition inhibitor, and zinc iodide may also be added.

A molten salt can also be used as the electrolyte. Preferred examples of the molten salt include an ionic liquid containing an imidazolium or a triazolium-type cation, an oxazolidine system, a pyridinium system, a guanidium system, and a combination thereof. For these cationic systems, it is also possible to combine with specific anions. For these molten salts, additives may also be added. It may also have a liquid crystal substituent. Further, a molten salt of a quaternary ammonium salt system can also be used.

The molten salt other than the above may be, for example, a liquidity imparted at room temperature by mixing polyethylene oxide with at least one lithium salt (for example, lithium acetate or lithium perchlorate). .

A gelling agent may also be added to the electrolyte containing the electrolyte and the solvent. The gelation is carried out, whereby the electrolyte is pseudo-solidified (hereinafter, the electrolyte to be solidified is also referred to as "quasi-solid electrolyte"). Examples of the gelling agent include an organic compound having a molecular weight of 1,000 or less, an Si-containing compound having a molecular weight of 500 to 5,000, an organic salt obtained from a specific acidic compound and a basic compound, a sorbitol derivative, and polyvinylpyridine.

Further, a method of blocking a matrix polymer, a crosslinked polymer compound or a monomer, a crosslinking agent, an electrolyte, and a solvent in a polymer can also be used.

The matrix polymer is preferably a polymer having a nitrogen-containing heterocyclic ring in a repeating unit of a main chain or a side chain, and a crosslinked body obtained by reacting the nitrogen-containing heterocyclic ring with an electrophilic compound, and having a triazine. Polymer of structure, polymer having guanidine structure, polymer containing compound, polymer having ether bond, polyvinylidene fluoride, methacrylate/acrylate, thermosetting resin, cross-linked poly A crystal cage compound such as a decane, a polyvinyl alcohol (PVA), a polyalkylene glycol, or a dextrin, a system in which an oxygen-containing or sulfur-containing polymer is added, or a natural polymer. Further, a base swelling type polymer or a polymer having a compound capable of forming a charge transfer complex of a cation moiety and iodine in one polymer may be added to the polymer.

As the polymer matrix, a system containing a crosslinked polymer obtained by reacting a bifunctional or higher isocyanate with a functional group such as a hydroxyl group, an amine group or a carboxyl group may be used. Further, a crosslinking method of reacting a hydroquinone alkyl group with a double bond compound, a polysulfonic acid or a polycarboxylic acid, and the like, and a metal ion compound having a divalent or higher valence may be used.

a solvent which can be preferably used in combination with the above pseudosolid electrolyte A mixed solvent containing a specific phosphate ester or ethyl carbonate, a solvent having a specific relative dielectric constant, and the like can be given. The liquid electrolyte solution may be held in the solid electrolyte membrane or the pores. The method preferably includes a cloth-like solid such as a conductive polymer membrane, a fibrous solid, or a filter.

Instead of the above liquid electrolyte and pseudo-solid electrolyte, a solid charge transport layer such as a p-type semiconductor or a hole transport material (for example, CuI, CuNCS, or the like) may be used. Further, an electrolyte described in "Nature", Vol. 486, p. 487 (2012) or the like can also be used. The organic charge transport layer can also use an organic hole transport material. The organic hole transporting material is preferably a conductive polymer such as polythiophene, polyaniline, polypyrrole or polydecane, or a spiro compound or a triarylamine having a tetrahedral central element such as C or Si. An aromatic amine derivative, a triphenylene derivative, a nitrogen-containing heterocyclic derivative, and a liquid crystalline cyano derivative.

Redox couples become carriers of electrons and therefore require some concentration. The concentration is preferably 0.01 mol/L or more, more preferably 0.1 mol/L or more, and particularly preferably 0.3 mol/L or more. The upper limit in this case is not particularly limited and is usually about 5 mol/L.

-Co-adsorbent -

In the photoelectric conversion element of the present invention, it is preferred to use a co-adsorbent together with the metal complex dye of the present invention or a dye which is used in combination as needed. Such a co-adsorbent is preferably a co-adsorbent having one or more acidic groups (preferably a carboxyl group or a salt thereof), and examples thereof include a fatty acid or a compound having a steroid skeleton. The fatty acid may be a saturated fatty acid or an unsaturated fatty acid, and examples thereof include butyric acid, caproic acid, caprylic acid, and cesium. Acid, hexadecanoic acid, dodecanoic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linoleic acid, and the like.

Examples of the compound having a steroid skeleton include cholic acid, glycocholic acid, chenodeoxycholic acid, hyocholic acid, deoxycholic acid, and lithocholic acid. Acid), ursodeoxycholic acid, etc. Preferred are cholic acid, deoxycholic acid, chenodeoxycholic acid, and more preferably chenodeoxycholic acid.

A preferred co-adsorbent is a compound represented by the following formula (CA).

In the formula, R ^A1 represents a substituent having an acidic group. R ^A2 represents a substituent. nA represents an integer of 0 or more.

The acidic group is synonymous with Anc ¹ to Anc ³ in the formula (AL-1) and the formula (AL-2), and the preferred range is also the same.

Preferred as R ^A1 is an alkyl group substituted with a carboxyl group or a sulfonic acid group or a salt thereof, more preferably -CH(CH ₃ )CH ₂ CH ₂ CO ₂ H, -CH(CH _{3 )} CH ₂ CH ₂ CONHCH ₂ CH ₂ SO ₃ H.

R ^A2 may, for example, be a substituent T to be described later, and among them, an alkyl group, a hydroxyl group, a decyloxy group, an alkylaminocarbonyloxy group, an arylaminocarbonyloxy group, and more preferably an alkyl group, a hydroxyl group or a hydrazine are preferable. Oxygen.

nA is preferably 2 to 4.

Specific examples of such specific compounds include compounds exemplified as the above-described compound having a steroid skeleton.

The co-adsorbent used in the present invention has an effect of suppressing the inefficient association of the dye by adsorbing on the semiconductor fine particles, and preventing the redox system from the surface of the semiconductor fine particles to the electrolyte. The effect of reverse electron transfer. The amount of the co-adsorbent used is not particularly limited, and from the viewpoint of effectively exhibiting the above effects, it is preferably from 1 mol to 200 mol with respect to the above-mentioned dye 1 mol, more preferably 10 moles ~ 150 moles, especially good 20 moles ~ 50 moles.

<Substituent T>

The expression of a compound (including a complex or a dye) in the present specification is used in the following meanings: in addition to the compound itself, a salt thereof and an ion thereof are also included. Further, in the present specification, the substituent which is not substituted or unsubstituted (the same applies to the linking group and the ligand) means that any substituent may be added to the group. Compounds that are not labeled as substituted or unsubstituted are also synonymous with this. Preferred substituents include the following substituents T.

Further, in the present specification, when only a substituent is described, the substituent T is referred to, and when each group, for example, only an alkyl group is described, the substituent T is applied. Preferred ranges and specific examples of the corresponding bases.

The substituent T can be exemplified below.

The alkyl group (preferably having a carbon number of 1 to 20, such as methyl, ethyl, isopropyl, tert-butyl, pentyl, heptyl, 1-ethylpentyl, benzyl, 2) - ethoxyethyl, 1-carboxymethyl, trifluoromethyl, etc.), alkenyl (preferably having a carbon number of 2 to 20, such as a vinyl group, an allyl group, an oleyl group, etc.), an alkynyl group (preferably having a carbon number of 2 to 20, such as an ethynyl group, a butynyl group, a phenylethynyl group, etc.) or a cycloalkyl group (preferably having a carbon number of 3 to 20, such as a cyclopropyl group or a cyclopentyl group). , cyclohexyl, 4-methylcyclohexyl, etc.), cycloalkenyl (preferably having a carbon number of 5 to 20, such as a cyclopentenyl group, a cyclohexenyl group, etc.), an aryl group (preferably a carbon number) 6~26, such as phenyl, 1-naphthyl, 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl, etc.), heterocyclic group (preferably having a carbon number of 2~) 20, more preferably a 5-membered or 6-membered heterocyclic group having at least one oxygen atom, a sulfur atom or a nitrogen atom, such as 2-pyridyl, 4-pyridyl, 2-imidazolyl, 2-benzene And imidazolyl, 2-thiazolyl, 2-oxazolyl, etc.), alkoxy (preferably having a carbon number of 1 to 20, such as methoxy, ethoxy, isopropoxy, benzyloxy, etc.) Ole a base (preferably having a carbon number of 2 to 20, such as a vinyloxy group, an allyloxy group, etc.) or an alkynyloxy group (preferably having a carbon number of 2 to 20, for example, 2-propynyloxy group, 4- a butynyloxy group, etc., a cycloalkoxy group (preferably having a carbon number of 3 to 20, such as a cyclopropoxy group, a cyclopentyloxy group, a cyclohexyloxy group, a 4-methylcyclohexyloxy group, etc.), An aryloxy group (preferably having a carbon number of 6 to 26, such as a phenoxy group, a 1-naphthyloxy group, a 3-methylphenoxy group, a 4-methoxyphenoxy group, etc.) or a heterocyclic oxy group ( For example, imidazolyloxy, benzimidazolyloxy, thiazolyloxy, benzothiazolyloxy, triazinyloxy, decyloxy), Alkoxycarbonyl (preferably having a carbon number of 2 to 20, such as an ethoxycarbonyl group, a 2-ethylhexyloxycarbonyl group, etc.) or a cycloalkoxycarbonyl group (preferably having a carbon number of 4 to 20, For example, a cyclopropoxycarbonyl group, a cyclopentyloxycarbonyl group, a cyclohexyloxycarbonyl group or the like), an aryloxycarbonyl group (preferably having a carbon number of 6 to 20, for example, a phenoxycarbonyl group, a naphthyloxycarbonyl group, etc.), Amino group (preferably having a carbon number of 0 to 20, comprising an alkylamino group, an alkenylamino group, an alkynylamino group, a cycloalkylamino group, a cycloalkenylamino group, an arylamino group, a heterocyclic amine Base, for example, an amine group, N,N-dimethylamino group, N,N-diethylamino group, N-ethylamino group, N-allylamino group, N-(2-propynyl group) Amino, N-cyclohexylamino, N-cyclohexenylamino, anilino, pyridylamino, imidazolylamino, benzimidazolylamino, thiazolylamino, benzothiazolylamino , a triazinylamino group, etc., an amine sulfonyl group (preferably a sulfonyl group having a carbon number of 0 to 20, preferably an alkyl group, a cycloalkyl group or an aryl group, such as N, N-di Methylamine sulfonyl group, N-cyclohexylamine sulfonyl group, N-phenylamine sulfonyl group, etc., fluorenyl group (preferably having a carbon number of 1 to 20, such as an ethylene group, a ring) a hexylcarbonyl group, a benzhydryl group, etc., a decyloxy group (preferably having a carbon number of 1 to 20, such as an ethoxylated group, a cyclohexylcarbonyloxy group, a benzhydryloxy group, etc.), an amine formazan group ( Preferred is an alkylmercapto group having a carbon number of from 1 to 20, preferably an alkyl group, a cycloalkyl group or an aryl group, such as N,N-dimethylaminecarbamyl, N-cyclohexylamine formazan. a group, a N-phenylamine carbenyl group, etc., a mercaptoamine group (preferably a mercaptoamine group having a carbon number of 1 to 20, such as an ethyl fluorenylamino group, a cyclohexylcarbonylamino group, a benzamidine group) Amino group, etc., sulfonamide group (preferably a sulfonium group having a carbon number of 0 to 20, preferably an alkyl group, a cycloalkyl group or an aryl group, such as a methylsulfonylamino group or a benzenesulfonyl group) An amidino group, a N-methylmethanesulfonamide group, an N-cyclohexylsulfonylamino group, an N-ethylbenzenesulfonylamino group, etc., an alkylthio group (preferably having a carbon number of 1 to 20, For example, methylthio, ethylthio, isopropylthio, benzylthio, etc.), cycloalkylthio (preferably having a carbon number of 3 to 20, such as cyclopropylthio, cyclopentylthio, cyclohexylsulfide) Base, 4-methylcyclohexylthio group, etc., arylthio group (preferably having a carbon number of 6 to 26, such as phenylthio, 1-naphthylthio, 3-methylphenylthio, 4-methyl) An oxyphenylthio group, etc., an alkylsulfonyl group, a cycloalkylsulfonyl group or an arylsulfonyl group (preferably having a carbon number of 1 to 20, such as a methylsulfonyl group or an ethylsulfonyl group) , cyclohexylsulfonyl, phenylsulfonyl, etc.), decylalkyl (preferably having a carbon number of 1 to 20, preferably a decyl group substituted by an alkyl group, an aryl group, an alkoxy group and an aryloxy group) For example, triethyl decyl, triphenyl decyl, diethyl benzyl sulfonyl, dimethyl phenyl decyl, etc., decyloxy (preferably having a carbon number of 1 to 20, preferably a decyloxy group substituted with an alkyl group, an aryl group, an alkoxy group and an aryloxy group, for example, a triethyl decyloxy group, a triphenyl sulfenyloxy group, a diethylbenzyl fluorenyloxy group, Dimethylphenyl decyloxy group, etc.), hydroxyl group, cyano group, nitro group, halogen atom (for example, fluorine atom, chlorine source) a bromine atom, an iodine atom, etc.), a carboxyl group, a sulfonic acid group, a phosphonium group, a phosphonium group, a boronic acid group, more preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a heterocyclic group or an alkoxy group. a group, a cycloalkoxy group, an aryloxy group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an amine group, a mercaptoamine group, a cyano group or a halogen atom, particularly preferably an alkyl group, an alkenyl group, a heterocyclic group, Alkoxy, alkoxycarbonyl, amine, decylamino or cyano.

When the compound, the substituent or the like contains an alkyl group, an alkenyl group or the like, these may be linear or branched, and may be substituted or unsubstituted. Further, when an aryl group, a heterocyclic group or the like is contained, these may be monocyclic or condensed, and may be substituted or unsubstituted.

<counter electrode (opposite electrode)>

The counter electrode preferably functions as a positive electrode of a dye-sensitized solar cell (photoelectrochemical cell). The counter electrode is generally synonymous with the above-described conductive support, and the support is not necessarily required in a configuration in which the strength is sufficiently maintained. The structure of the opposite electrode is preferably a structure having a high current collecting effect. In order for light to reach the photoreceptor layer, at least one of the aforementioned conductive support and the opposite electrode must be substantially transparent. In the dye-sensitized solar cell of the present invention, it is preferred that the conductive support is transparent and that sunlight is incident from the support side. In this case, it is more preferable that the opposite electrode has a property of reflecting light. The counter electrode of the dye-sensitized solar cell is preferably a glass or a metal obtained by vapor-depositing a metal or a conductive oxide, and particularly preferably a glass in which platinum is vapor-deposited. In the dye-sensitized solar cell, in order to prevent evapotranspiration of the constituent, it is preferred to seal the side surface of the battery by a polymer or an adhesive.

The present invention is applicable to Japanese Patent No. 4260494, Japanese Patent Laid-Open No. 2004-146425, Japanese Patent Laid-Open No. 2000-340269, Japanese Patent Laid-Open No. Publication No. 2002-289274, and Japanese Patent Laid-Open No. 2004-152613 A photoelectric conversion element and a dye-sensitized solar cell described in Japanese Laid-Open Patent Publication No. Hei 9-27352. Further, it is applicable to Japanese Patent Laid-Open Publication No. 2004-152613, Japanese Patent Laid-Open No. 2000-90989, Japanese Patent Laid-Open Publication No. 2003-217688, Japanese Patent Laid-Open Publication No. 2002-367686, and Japanese Patent Publication No. 2003 Japanese Laid-Open Patent Publication No. 2001-43907, Japanese Patent Laid-Open No. 2000-340269, Japanese Patent Laid-Open No. Hei No. Hei No. Hei. No. Hei. No. 2005-85500, Japanese Patent Laid-Open No. 2004-273272, Japanese Patent Laid-Open No. 2000 -323190, Japanese Patent Laid-Open No. 2000-228234, Japan Japanese Laid-Open Patent Publication No. 2001-266963, Japanese Patent Laid-Open Publication No. 2001-185244, Japanese Patent Laid-Open Publication No. 2001-525108, Japanese Patent Laid-Open No. 2001-203377, Japanese Patent Laid-Open No. 2000-100483, Japan JP-A-2001-210390, JP-A-2002-280587, JP-A-2001-273937, JP-A-2000-285977, JP-A-2001-320068, and the like Among the photoelectric conversion elements and dye-sensitized solar cells described.

<<Pigment solution, dye-adsorbing electrode using the same, and method for producing dye-sensitized solar cell>>

In the present invention, it is preferred to use a dye solution containing the metal complex dye of the present invention to produce a dye-adsorbing electrode.

Such a dye solution is obtained by dissolving the metal complex dye of the present invention in a solvent, and may optionally contain a co-adsorbent or other components.

The solvent to be used is disclosed in JP-A-2001-291534, but is not particularly limited. In the present invention, an organic solvent is preferred, and an alcohol, a guanamine, a nitrile, a hydrocarbon, and a mixed solvent of two or more of these are more preferred. The mixed solvent is preferably a mixed solvent of an alcohol and a solvent selected from the group consisting of guanamines, nitriles or hydrocarbons. More preferred are mixed solvents of alcohols and guanamines, alcohols and hydrocarbons, and particularly preferred are mixed solvents of alcohols and guanamines. Particularly preferred are methanol, ethanol, propanol, butanol, dimethylformamide, and dimethylacetamide.

The dye solution preferably contains a co-adsorbent, and the co-adsorbent is preferably the above-mentioned co-adsorbent, and among them, a compound represented by the above formula (CA) is preferred.

Here, in the case of producing the photoelectric conversion element or the dye-sensitized solar cell of the dye solution of the present invention, in order to directly use the solution, a dye solution in which the concentration of the metal complex dye or the co-adsorbent is adjusted is preferable. In the present invention, it is preferred to contain 0.001% by mass to 0.1% by mass of the metal complex dye of the present invention.

It is particularly preferable to adjust the moisture content in the dye solution. Therefore, in the present invention, it is preferred to adjust the water content (content ratio) to 0% by mass to 0.1% by mass.

Similarly, in order to effectively achieve the effects of the present invention, it is preferable to adjust the moisture content of the electrolytic solution in the photoelectric conversion element or the dye-sensitized solar cell, and therefore, it is preferred that the moisture content (content ratio) of the electrolytic solution ) Adjusted to 0% by mass to 0.1% by mass. The adjustment of the electrolytic solution is particularly preferably carried out by a dye solution.

In the present invention, a dye-adsorbing electrode which is a semiconductor electrode for a dye-sensitized solar cell in which the metal complex dye is supported on the surface of the semiconductor fine particles of the semiconductor electrode is preferably used.

In other words, it is preferable that the dye-adsorbing electrode for a dye-sensitized solar cell is obtained by applying a composition obtained from the dye solution to a conductive support to which semiconductor fine particles are applied, and curing the composition after coating. Made into a photoreceptor layer.

In the present invention, it is preferred to use the dye-adsorbing electrode for a dye-sensitized solar cell, prepare an electrolyte, and a counter electrode, and assemble the dye-sensitized solar cell by using these.

[Examples]

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Example 1 (Synthesis of Metal Complex Pigment)

Hereinafter, the method for synthesizing the metal complex dye of the present invention will be described in detail, but the starting material, the dye intermediate, and the synthesis route are not limited thereto.

(Synthesis of Metal Complex Pigment A-13)

The metal complex dye A-13 was synthesized according to the following synthetic scheme.

The commercially available compound A-13-1 was coupled with the compound A-13-1-1 under tetrakis(triphenylphosphine)palladium catalyst to obtain the compound A-13-2. The anion of the benzyl group obtained by treating the compound A-13-2 with LDA (lithium diisopropylamide) is reacted with the aldehyde A-13-S to carry out dehydration, thereby obtaining a ligand A- 13-3. This ligand was reacted with the compound d-1-7, and then the compound A-13-5 and NH ₄ SCN (ammonium thiocyanate) were sequentially added thereto, followed by heating and stirring to obtain a compound A-13-6. Finally, the ester is hydrolyzed to obtain a metal complex dye A-13.

(Synthesis of Metal Complex Pigment A-29)

The metal complex dye A-29 was synthesized in accordance with the following synthetic scheme.

(i) Synthesis of Compound A-29-2

Compound A-29-1 15.0 g, 2-(3-hexylthiophen-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborane 20.5 mL, carbonic acid Potassium 26.0 g, 1,1'-bis(diphenylphosphino)ferrocene-palladium(II) chloride-dichloromethane complex 5.1 g, THF (tetrahydrofuran) 150 mL, and pure water 150 mL were placed in 500 mL. The three-necked flask was heated under reflux for 3 hours under a nitrogen atmosphere. The resulting solution was returned to room temperature, and after neutralizing with ammonium chloride, the reaction product was extracted with ethyl acetate. The organic phase was concentrated and purified by silica gel column chromatography to give Compound A-29-2 13 g.

(ii) Synthesis of Ligand A-29-3

5.0 g of compound A-29-2, 15.2 g of potassium phosphate, 45 mL of THF, 45 mL of pure water, 0.2 g of palladium acetate, and S-Phos (2-dicyclohexylphosphino-2',6'-dimethoxyl linkage Benzene) 0.88g, 4,4,5,5-tetramethyl-1-2-[4-(trifluoromethyl)phenyl]-1,3,2-dioxaborane 5.83g The 200 mL three-necked flask was heated under reflux for 3 hours under a nitrogen atmosphere. The resulting solution was returned to room temperature, and after neutralizing with ammonium chloride, the reaction product was extracted with ethyl acetate. The organic phase was concentrated and purified by silica gel column chromatography to obtain 3.8 g of the ligand A-29-3.

(iii) Synthesis of Compound A-29-5

4.0 g of the compound A-29-4, 2.42 g of cesium chloride, and 90 mL of ethanol were placed in a 200 mL three-necked flask, and the mixture was heated under reflux for 4 hours under a nitrogen atmosphere. The obtained precipitate was filtered and washed with ethanol to obtain 5.6 g of Compound A-29-5.

(iv) Synthesis of Compound A-29-6

1.73 g of compound A-29-5, 1.02 g of compound A-29-3, 27 mL of DMF (N,N-dimethylformamide) and 2.44 g of tributylamine were placed in a three-necked flask under nitrogen atmosphere. The heating was carried out for 3 hours at 140 °C. After the resulting solution was returned to room temperature, it was concentrated, and purified by silica gel column chromatography to obtain 0.5 g of Compound A-29-6.

(v) Synthesis of Compound A-29-7

A mixture of 0.5 g of compound A-29-6, 52.3 mg of ammonium thiocyanate, 10 mL of DMF, and 1.0 mL of pure water was placed in a 20 mL glass vessel at 160 ° C. Heat in the microwave for 10 minutes. The resulting solution was concentrated and purified by silica gel column chromatography to give Compound A-29-7 0.16 g.

(vi) Synthesis of metal complex pigment A-29

160 mL of Compound A-29-7, DMF 42 mL, and 1 N aqueous NaOH solution were placed in a 100 mL eggplant-shaped flask, and allowed to react at room temperature. The obtained solution was adjusted to pH 2.9 with TfOH (trifluoromethanesulfonic acid), filtered, and then washed with ultrapure water to obtain 120 mg of the metal complex dye A-29.

The visible absorption spectrum of the obtained metal complex dye A-29 is shown in Fig. 3 .

This spectrum was measured at a concentration of 17 μmol/L using UV-3600 manufactured by Shimadzu Corporation.

Fig. 3 is a spectrum chart in which the solvent is measured as DMF.

The other metal complex dyes described in Table 1 can also be synthesized by the same method as described above or a method based thereon.

The structure of the obtained metal complex dye was confirmed by MS (mass spectrometry) measurement.

The measurement results of the mass spectrum are shown in Table 1 below.

Example 2 (Production of dye-sensitized solar cell)

A photoelectrode having the same configuration as that of the photoelectrode 12 shown in FIG. 5 described in Japanese Laid-Open Patent Publication No. 2002-289274 is produced by the following procedure, and the photoelectrode is further used instead of the Japanese Patent Laid-Open In addition to the photoelectrode shown in FIG. 3 of JP-A-2002-289274, a dye-sensitized solar cell having the same effect as that of FIG. 3 was produced. 20-color-sensitized solar cell of 10 mm × 10 mm in the same configuration. The specific structure is shown in Figure 2. In FIG. 2, 41 is a transparent electrode, 42 is a semiconductor electrode, 43 is a transparent conductive film, 44 is a substrate, 45 is a semiconductor layer, 46 is a light scattering layer, 40 is a photoelectrode, 20 is a dye-sensitized solar cell, CE For the opposite electrode, E is the electrolyte and S is the spacer.

(Preparation of paste)

(Paste A) A titanium dioxide slurry was prepared by adding spherical TiO ₂ particles (anatase, average particle diameter: 25 nm, hereinafter referred to as spherical TiO ₂ particles A) to a nitric acid solution and stirring. Next, a cellulose-based binder as a bismuth adhesive was added to the titanium dioxide slurry, and kneaded to prepare a paste A.

(Paste 1) prepared by adding spherical TiO ₂ particles A and spherical TiO ₂ particles (anatase, average particle diameter: 200 nm, hereinafter referred to as spherical TiO ₂ particles B) to a nitric acid solution and stirring Titanium dioxide slurry. Next, a cellulose-based binder as a bismuth binder was added to the titanium dioxide slurry, and kneading was carried out to prepare a paste 1 having a mass of TiO ₂ particles A of TiO ₂ particles B of 30:70.

(Paste 2) The mass of the rod-shaped TiO ₂ particles C was prepared by mixing rod-shaped TiO ₂ particles (anatase, diameter: 100 nm, aspect ratio: 5, hereinafter referred to as rod-shaped TiO ₂ particles C) in the paste A. : Paste 2 of mass A = 30:70.

(Production of semiconductor electrode)

A transparent electrode 41 (conductive support) having a fluorine-doped SnO ₂ conductive film (transparent conductive film 43 and film thickness: 500 nm) was formed on a glass substrate (substrate 44). Next, the paste 1 was screen-printed on the SnO ₂ conductive film, and then dried. Thereafter, calcination was carried out in the air at 450 °C. Further, the paste electrode 2 is subjected to screen printing and firing, and a semiconductor electrode having the same structure as that of the semiconductor electrode 42 shown in FIG. 2 is formed on the SnO ₂ conductive film (area of the light-receiving surface: 10 mm × 10 mm, layer Thickness: 10 μm, thickness of the semiconductor layer: 6 μm, thickness of the light-scattering layer: 4 μm, content of the rod-shaped TiO ₂ particles C contained in the light-scattering layer: 30% by mass) (photosensitive layer), and the production is not included The photoelectrode of the pigment.

(pigment adsorption)

Next, the dye was adsorbed onto the semiconductor electrode (precursor of the dye adsorption electrode) in the manner shown below. First, a 1:1 (volume ratio) mixture of a third butanol and dimethylformamide which was dehydrated by magnesium ethoxide was dissolved as a solvent at a concentration of 3 × 10 ^-4 mol/L. The metal complex dye described in Table 2 below was further prepared by adding a molar mixture of 20 mol of chenodeoxycholic acid and cholic acid as a co-adsorbent to the 1 mol organic compound dye. Pigment solution. The water content of each of the dye solutions was measured by Karl Fisher titration, and as a result, any of the dye solutions was less than 0.01% by mass of water. Next, the semiconductor electrode was immersed in each dye solution at 40 ° C for 10 hours, and then lifted at 50 ° C to dry, thereby separately adsorbing about 2 × 10 ^-7 mol / cm ² of the pigment on the semiconductor electrode. Photoelectrode 40.

(Assembling of pigment-sensitized solar cells)

Next, a platinum electrode (thickness of Pt film: 100 nm) having the same shape and size as that of the above-described photoelectrode 40 was prepared as a counter electrode CE, and iodine 0.1 M, lithium iodide 0.05 M, and 4-tert-butylpyridine 0.25 were prepared. M iodine redox acetonitrile solution As an electrolyte. Further, a spacer S (trade name: "Surlyn") manufactured by DuPont Co., Ltd. having a shape matching the size of the semiconductor electrode is prepared, and the photoelectrode 40 and the counter electrode CE are opposed to each other via the spacer S, and are carried out. The thermocompression bonding is performed to internally fill the above electrolyte (forming a charge transporting body layer). The outer periphery of the battery and the electrolyte injection port were sealed and cured by using resin XNR-5516 manufactured by Nagase Chemical Co., Ltd., and each dye-sensitized solar cell was completed (sample No. 101 - sample No. 127 and test) Sample number c11~sample number c15). The performance of the dye-sensitized solar cell was evaluated as described below.

(Evaluation Experiment 1)

Perform a battery characteristic test to determine the short-circuit current density (Jsc, unit mA/cm ² ), open circuit voltage (Voc, unit is v), and fill factor (FF) of the dye-sensitized solar cell, divided by the battery output. The initial photoelectric conversion efficiency [η (%)] was calculated from the incident energy. The battery characteristic test used a solar simulator (PEC-L12 manufactured by Peccell Technologies, Inc.). The characteristic evaluation was performed using an IV characteristic measuring device (PECK2400-N) manufactured by Peccell Technology Co., Ltd. The evaluation was performed on five units under the same conditions, and the initial photoelectric conversion efficiency evaluation results indicated the average values. Moreover, the unevenness of the initial photoelectric conversion efficiency was evaluated by the standard deviation. The results obtained were evaluated by the following evaluation criteria.

Initial photoelectric conversion efficiency evaluation benchmark

A: the photoelectric conversion efficiency is 1.3 times or more with respect to the initial photoelectric conversion efficiency of the sample c11

B: The photoelectric conversion efficiency is 1.1 times or more and less than 1.3 times with respect to the initial photoelectric conversion efficiency of the sample c11

C: the photoelectric conversion efficiency is less than 1.1 times with respect to the initial photoelectric conversion efficiency of the sample c11

In addition, it is shown as initial performance in Table 2 below.

Evaluation criteria for unevenness of initial photoelectric conversion efficiency

A: The standard deviation is less than 0.07

B: The standard deviation is 0.07 or more and less than 0.15

C: standard deviation is 0.15 or more

In addition, it is shown in Table 2 below as the initial performance unevenness.

(Evaluation Experiment 2)

The photoelectric conversion efficiency (η ₂₀₀ ) of the above-described dye-sensitized solar cell was allowed to stand in an environment of 65 ° C for 200 hours, and the ratio was defined as the deterioration rate.

In other words, the initial photoelectric conversion efficiency (η ₀ ) was used, and the deterioration rate was determined according to the following formula.

Deterioration rate = (η _{0 -} η ₂₀₀ ) ÷ η ₀ × 100

The evaluation was carried out under the same conditions to produce five units, and the deterioration rate evaluation results indicated the average values. Moreover, the unevenness of the deterioration rate is evaluated by the standard deviation. The results obtained were evaluated by the following evaluation criteria.

Deterioration rate evaluation standard

A: The degradation rate is negative (benign)

B: Deterioration rate is 0~10%

C: Deterioration rate exceeds 10%

In addition, it is shown in Table 2 as thermal durability.

Evaluation criteria for unevenness of deterioration rate

A: Standard deviation is less than 2%

B: The standard deviation is 2% or more and less than 5%

C: standard deviation is 5% or more

In addition, it is shown in Table 2 as the unevenness of thermal durability.

The results obtained are collectively shown in Table 2 below.

[化36]

Further, the comparative compound 2 is the compound 3 described in JP-A-2009-51999, and the comparative compound 5 is a compound described in the specification of International Publication No. 2009/131183.

According to Table 2, it is understood that the photoelectric conversion elements of the present invention are excellent in initial photoelectric conversion efficiency and high in durability.

Moreover, it is understood that the unevenness of these properties in the reverse manufacturing is small.

1‧‧‧Electrical support

2‧‧‧Photoreceptor layer

3‧‧‧ Charge Transfer Body Layer

4‧‧‧relative electrode

5‧‧‧Photoelectrode

6‧‧‧ Circuitry

10‧‧‧ photoelectric conversion components

21‧‧‧ Pigment (metal complex pigment)

22‧‧‧Semiconductor particles

100‧‧‧System for the use of dye-sensitized solar cells

M‧‧‧Action Agency

Claims (18)

A photoelectric conversion element comprising a conductive support, a photoreceptor layer containing an electrolyte, a charge transfer body layer containing an electrolyte, and a counter electrode, wherein the photoreceptor layer carries a metal error represented by the following formula (I) Semiconductor microparticles of the pigment: M(LD)(LA)(Z). (CI) In the formula (I), M represents a metal ion; LD represents a bidentate ligand represented by the following formula (DL-1); LA represents the following formula (AL-1) or formula ( a 3-dental ligand represented by AL-2); Z represents a monodentate ligand; CI represents a counter ion necessary for neutralizing the charge; In the formula (DL-1), ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring; Y ¹ represents a carbon atom or a nitrogen atom, and ring C1 represents a above-mentioned M by a carbanion. A monocyclic or condensed aryl or heteroaryl ring; R ^A is a group represented by the following formula (U); R ^B represents a substituent; and R ^C represents a halogen atom, an alkyl group, a cycloalkyl group, or a fluorene group; a group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group or a nitro group; a1 represents an integer of 1 to 4, and a2 represents an integer of 0 to 3, A3 represents an integer of 0 or more; in the case where a plurality of R ^A , R ^B and R ^C are respectively present, the plurality may be the same or different; In the formula (U), L ^u represents a single bond, a vinyl group or an ethynyl group; the ring X ^u represents an extended aryl group or a heteroaryl group, q represents an integer of 0 to 2; and R ^u represents a linear or branched alkane. a group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group; wherein, in the case where the above ring X ^u is an exoaryl group, the above R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group; nu represents an integer of 1 to 4, and when nu is 2 or more, a plurality of R ^u may be They may be the same or different from each other, or may be bonded to each other to form a ring; [Chemical 3] In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ each independently represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which any of these protons are dissociated. ; R ^AL represents a substituent, and b1 represents an integer of 0-4. The photoelectric conversion element according to claim 1, wherein the above M is Fe ²⁺ , Ru ²⁺ or Os ²⁺ . The photoelectric conversion element according to claim 1, wherein the ring C1 is a thiophene ring, a furan ring, a pyrrole ring or a benzene ring. The photoelectric conversion element according to claim 1, wherein the ring X ^u is a heteroaryl ring group. The photoelectric conversion element according to claim 1, wherein the ring X ^u is a thiophene ring group or a furan ring group. The photoelectric conversion element according to claim 1, wherein the ^Lu is a single bond, the q is 0, and the ^Ru is an amine group, an alkylamino group or an arylamine group. The photoelectric conversion element according to claim 1, wherein the ring A is a pyridine ring. The photoelectric conversion element according to claim 1, wherein the LA is expressed by the above formula (AL-1). The photoelectric conversion element according to any one of the first aspect, wherein the semiconductor fine particles further carry a co-adsorbent having one or more acidic groups. The photoelectric conversion element according to claim 9, wherein the co-adsorbent is represented by the following formula (CA): In the formula, R ^A1 represents a substituent having an acidic group; R ^A2 represents a substituent; and nA represents an integer of 0 or more. A dye-sensitized solar cell comprising the photoelectric conversion element according to claim 1 of the patent application. A metal complex pigment represented by the following formula (I): M(LD)(LA)(Z). (CI) In the formula (I), M represents a metal ion; LD represents a bidentate ligand represented by the following formula (DL-1); LA represents the following formula (AL-1) or formula ( a 3-dental ligand represented by AL-2); Z represents a monodentate ligand; CI represents a counter ion necessary for neutralizing the charge; In the formula (DL-1), ring A represents a nitrogen-containing hetero ring selected from the group consisting of a pyridine ring, a pyrimidine ring and a pyridazine ring; Y ¹ represents a carbon atom or a nitrogen atom, and ring C1 represents a above-mentioned M by a carbanion. A monocyclic or condensed aryl or heteroaryl ring; R ^A is a group represented by the following formula (U); R ^B represents a substituent; and R ^C represents a halogen atom, an alkyl group, a cycloalkyl group, or a fluorene group; a group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group or a nitro group; a1 represents an integer of 1 to 4, and a2 represents an integer of 0 to 3, A3 represents an integer of 0 or more; in the case where there are a plurality of R ^A , R ^B and R ^C respectively, the ones may be the same or different from each other; [Chem. 6] In the formula (U), L ^u represents a single bond, a vinyl group or an ethynyl group; the ring X ^u represents an extended aryl group or a heteroaryl group, q represents an integer of 0 to 2; and R ^u represents a linear or branched alkane. a group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group, a decyloxy group, an amine group, an alkylamino group or an arylamine group; wherein, in the case where the above ring X ^u is an exoaryl group, the above R ^u is a linear or branched alkyl group, an alkoxy group, an alkylthio group, an alkynyl group, an alkenyl group or a decyloxy group; nu represents an integer of 1 to 4, and when nu is 2 or more, a plurality of R ^u may be They may be the same or different from each other, and may be bonded to each other to form a ring; In the formula (AL-1) and the formula (AL-2), Anc ¹ to Anc ³ each independently represent -CO ₂ H, -SO ₃ H, -PO ₃ H ₂ or a group in which any of these protons are dissociated. ; R ^AL represents a substituent, and b1 represents an integer of 0-4. a pigment solution which is dissolved as described in claim 12 The metal complex is pigmented. The pigment solution according to claim 13, wherein the organic solvent contains 0.001% by mass to 0.1% by mass of the metal complex dye, and the water content is 0.1% by mass or less. The pigment solution according to claim 13 or 14, wherein the dye solution further contains a co-adsorbent. The dye solution according to claim 15, wherein the co-adsorbent is represented by the following formula (CA): In the formula, R ^A1 represents a substituent having an acidic group; R ^A2 represents a substituent; and nA represents an integer of 0 or more. A dye-adsorbing electrode for a dye-sensitized solar cell, which is obtained by applying a dye solution according to claim 13 to a conductive support to which semiconductor fine particles are applied, and applying the composition The above composition is cured as a photoreceptor layer. A method for manufacturing a dye-sensitized solar cell, which is used as a patent application The dye-sensitized electrode for a dye-sensitized solar cell according to Item 17 is assembled with an electrolyte and a counter electrode.