JP2005078887A - Semiconductor for photoelectric conversion material, photoelectric conversion element and solar cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor for a photoelectric conversion material, a photoelectric conversion element and a solar battery which exhibit high photoelectric conversion efficiency and superior stability. <P>SOLUTION: The semiconductor for the photoelectric conversion material contains a heterocyclic compound expressed by a general formula (1) or a general formula (2). In the formula (1), R<SB>1</SB>expresses a substituent except a hydrogen atom or a hydroxy group, Z<SB>1</SB>expresses a group of atoms needed to form aromatic carbocycles or heterocycles, and L expresses methine chains of 1 to 5 each of which may have a divalent aromatic ring group or a heterocyclic group as a linking group at an end or in the middle. In the formula (2), Z<SB>1</SB>expresses the group of atoms needed to form the aromatic carbocycles or heterocycles, and L expresses methine chains of 1 to 5 each of which may have the divalent aromatic ring group or the heterocyclic group as the linking group. X<SB>1</SB>expresses O, NR<SB>8</SB>or S, and R<SB>8</SB>expresses the hydrogen atom, an aliphatic group, the aromatic group or the heterocyclic group. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a novel semiconductor for a photoelectric conversion material, a photoelectric conversion element, and a solar cell.

  A photoelectric conversion material is a material that converts light energy into electrical energy using an electrochemical reaction between electrodes. When the photoelectric conversion material is irradiated with light, electrons are generated on one electrode side and move to the counter electrode. The electrons that have moved to the counter electrode move as ions in the electrolyte and return to one electrode. That is, the photoelectric conversion material is a material that can continuously extract light energy as electric energy, and is used for, for example, a solar cell.

  There are several types of solar cells, but most of them are silicon solar cells that have been put to practical use in power generation panels for home installation, desk calculators, watches, portable game machines and the like.

  However, recently, dye-sensitized solar cells have attracted attention and are being studied for practical use. Dye-sensitized solar cells have been studied for a long time, and their basic structure specifically has a metal oxide semiconductor, a dye adsorbed thereon, an electrolyte solution, and a counter electrode as constituent elements.

  In the conventional dye-sensitized solar cell as described above, a photoelectric conversion material in which a spectral sensitizing dye having absorption in the visible light region is adsorbed on the semiconductor surface is used. For example, a solar cell having a spectral sensitizing dye layer such as a transition metal complex on the surface of a metal oxide semiconductor is described (for example, see Patent Document 1), and a titanium oxide semiconductor doped with metal ions Examples include a solar cell having a spectral sensitizing dye layer such as a transition metal complex on the surface of the layer (for example, see Patent Document 2).

On the other hand, as an oxide semiconductor electrode having photoelectric conversion ability, a semiconductor single crystal electrode has been used in the early days. The types include titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), and the like.

  However, since the single crystal electrode has a small amount of dye adsorption, the efficiency is very low and the cost is high. Thus, a high surface area semiconductor electrode formed by sintering fine particles and having a large number of pores has been conceived. Regarding high surface area semiconductor electrodes, for example, it has been reported by Tsubomura et al. That a porous zinc oxide electrode adsorbing an organic dye has very high performance (for example, see Non-Patent Document 1).

  Later, improvements were also made to the dye, and Graetzel et al. Now have a ruthenium complex dye adsorbed on a porous titanium oxide electrode, so that it now has the same performance as a silicon solar cell (for example, (Refer nonpatent literature 2.).

However, in order to commercialize silicon solar cell substitutes, higher energy conversion efficiency, higher short-circuit current, open-circuit voltage, and form factor are required than ever before. Technical development using ZnO, TiO ₂ , zirconium oxide (ZrO ₂ ), niobium oxide (Nb ₂ O ₅ ), etc. has been carried out as materials reported in the above.

  In addition, since the dye-sensitized wet solar cell has a very low manufacturing cost compared to the silicon solar cell, in the future, there is a possibility of replacing the silicon solar cell used in the various products described above. In that case, the characteristic of the solar cell according to each product becomes important. There are various characteristics of solar cells. 1. short circuit current; 2. Open voltage, Form factor, 4. 4. Energy conversion efficiency and The light absorption spectrum is important. In particular, the energy conversion efficiency of item 4 is the greatest problem for solar cells, and its improvement has been strongly desired. As one of the technical problems affecting the efficiency, there is a demand for a sensitizing dye having the ability to efficiently transfer photoexcited electrons to a semiconductor. Of the various dyes studied so far, the ruthenium complex dyes have been found to have relatively excellent characteristics, but the dyes are expensive and ruthenium, the central metal of the complex, is rare. Since it is an element and there is a concern about a stable supply in the future, an organic dye that can be supplied at a lower cost and more stably is more demanded.

In response to these requests, many organic dyes (for example, see Patent Documents 3 to 5) have been studied, and merocyanine dyes, xanthene dyes, coumarin dyes, acridine dyes, phenylmethane dyes, etc. Is well known. Further, other new dye mother nuclei have been developed (see, for example, Patent Document 6). However, the photoelectric conversion efficiency of each organic dye is not yet sufficient, and an organic dye that can constitute a photoelectric conversion element with higher conversion efficiency is desired.
Japanese Patent Laid-Open No. 1-220380 Japanese National Patent Publication No. 5-504023 JP-A-11-167937 Japanese Patent Laid-Open No. 11-214730 Japanese Patent Laid-Open No. 11-214731 JP 2001-76775 A Nature, 261 (1976) p402. J. et al. Am. Chem. Soc. 115 (1993) 6382

  This invention is made | formed in view of the said subject, The objective is to provide the semiconductor for photoelectric conversion materials, a photoelectric conversion element, and a solar cell which show the high photoelectric conversion efficiency and the outstanding stability.

The above object of the present invention is achieved by the following configurations.
(Claim 1)
The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (1) or General formula (2).

[In the formula, R ₁ represents a substituent other than a hydrogen atom or a hydroxy group, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, and L represents a conjugated chain. 5 methine chains, which may have a divalent aromatic ring group or heterocyclic group as a linking group at the terminal or in the middle. ]

[In the formula, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, L is 1 to 5 methine chains forming a conjugated chain, It may have a divalent aromatic ring group or heterocyclic group, X ₁ represents O, NR ₈ or S, and R ₈ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group. . ]
(Claim 2)
The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (3) or General formula (4).

[Wherein R ₁ represents a hydrogen atom or a substituent other than a hydroxy group, R ₂ , R ₃ and R ₄ each independently represents a hydrogen atom or a substituent, and R ₂ and R ₃ , R ₃ And R ₄ , R ₂ and R ₄ may each form a ring, Z ₁ represents an atomic group necessary to form an aromatic carbocycle or a heterocycle, n1 represents 0, 1 or 2 When n1 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other, and in adjacent repeating units, a ring is formed between R ₂ and R ₂ or R ₃ and R _3. Also good. ]

[Wherein, R ₁ represents a substituent other than a hydrogen atom or a hydroxyl group, R ₂ , R ₅ and R ₆ each independently represents a hydrogen atom or a substituent, and Z ₁ represents an aromatic carbocyclic or heterocyclic ring. Z ₂ represents an aromatic carbocyclic or heterocyclic ring, m 1 represents 1 or 2, and p 1 represents 0 or 1. ]
(Claim 3)
The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (5) or General formula (6).

[Wherein R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom or a substituent, and R ₂ and R ₃ , R ₃ and R ₄ , R ₂ and R ₄ each form a ring, Z ₁ represents an atomic group necessary for forming an aromatic carbocyclic or heterocyclic ring, X ₁ represents O, NR ₈ or S, and R ₈ represents a hydrogen atom, an aliphatic group or an aromatic group. Represents a group or a heterocyclic group, n2 represents 0, 1 or 2, and when n2 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other, and in the adjacent repeating unit, R ₂ And R ₂ , or R ₃ and R ₃ may form a ring. ]

[Wherein R ₂ , R ₅ and R ₆ each independently represents a hydrogen atom or a substituent, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, and Z ₂ represents an aromatic X ₁ represents O, NR ₈ or S, R ₈ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group, m2 represents 1 or 2, p2 represents 0 or 1. ]
(Claim 4)
A group of atoms necessary for forming the aromatic carbocycle or heterocycle represented by Z ₁ in the general formulas (1) to (6) is represented by the following general formula (7). The semiconductor for photoelectric conversion materials of any one of Claims 1-3.

[Wherein R ₉ , R ₁₀ and R ₁₁ each independently represents a hydrogen atom or a substituent, R ₁₂ and R ₁₃ each represents an aliphatic group, an aromatic group or a heterocyclic group, R ₁₀ and R ₁₃ , R ₁₁ and R ₁₂ , R ₁₂ and R ₁₃ may form a ring, and form a heterocyclic ring and a condensed ring at the position of *. ]
(Claim 5)
It is a metal oxide semiconductor or a metal sulfide semiconductor, The semiconductor for photoelectric conversion materials of any one of Claims 1-4 characterized by the above-mentioned.
(Claim 6)
The photoelectric conversion element semiconductor of any one of Claims 1-5 is provided on the electroconductive support body, The photoelectric conversion element characterized by the above-mentioned.
(Claim 7)
A solar cell comprising the photoelectric conversion element according to claim 6, a charge transfer layer, and a counter electrode.

  ADVANTAGE OF THE INVENTION According to this invention, the semiconductor for photoelectric conversion materials, a photoelectric conversion element, and a solar cell which show high photoelectric conversion efficiency and the outstanding stability can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have sensitized the compound with a specific structure as represented by the general formulas (1) to (7). A semiconductor for a photoelectric conversion material having high photoelectric conversion efficiency and excellent stability, which are the object effects of the present invention, was successfully obtained from a semiconductor.

  Details of the present invention will be described below.

<< Semiconductor for photoelectric conversion material >>
As a semiconductor used for the semiconductor for a photoelectric conversion material of the present invention, a simple substance such as silicon or germanium, a group 3 to group 5 of a periodic table (also referred to as an element periodic table), or a group 13 to group 15 system. A compound having an element, a metal chalcogenide (eg, oxide, sulfide, selenide, etc.), metal nitride, or the like can be used.

  Preferred metal chalcogenides include titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium or tantalum oxides, cadmium, zinc, lead, silver, antimony or Bismuth sulfide, cadmium or lead selenide, cadmium telluride and the like. Other compound semiconductors include phosphides such as zinc, gallium, indium and cadmium, gallium-arsenic or copper-indium selenide, copper-indium sulfide, titanium nitride, and the like.

Specific examples of the semiconductor according to the semiconductor for photoelectric conversion material of the present invention include TiO ₂ , SnO ₂ , Fe ₂ O ₃ , WO ₃ , ZnO, Nb ₂ O ₅ , CdS, ZnS, PbS, Bi ₂ S ₃ , CdSe. , CdTe, GaP, InP, GaAs, CuInS ₂ , CuInSe ₂ , Ti ₃ N _4, etc., but TiO ₂ , ZnO, SnO ₂ , Fe ₂ O ₃ , WO ₃ , Nb ₂ O are preferably used. ₅ , CdS, and PbS, and TiO ₂ or Nb ₂ O ₅ is more preferably used, and TiO ₂ is preferably used among them.

The semiconductor used for the photoelectric conversion material semiconductor of the present invention may be a combination of the above-described plurality of semiconductors. For example, several types of metal oxides or metal sulfides described above can be used in combination, or 20% by mass of titanium nitride (Ti ₃ N ₄ ) may be mixed and used in the titanium oxide semiconductor. In addition, J.H. Chem. Soc. , Chem. Commun. 15 (1999). At this time, when a component is added as a semiconductor in addition to the metal oxide or metal sulfide, the mass ratio of the additional component to the metal oxide or metal sulfide semiconductor is preferably 30% or less.

  High photoelectric conversion efficiency which is one of the objective effects of the present invention is obtained by sensitizing the semiconductor for photoelectric conversion material with any one compound represented by the general formulas (1) to (7). And the semiconductor for photoelectric conversion materials of this invention which has the outstanding stability can be obtained.

  Hereinafter, the heterocyclic compounds represented by the general formulas (1) to (7) will be described.

<< Heterocyclic Compound Represented by General Formula (1) >>
In the general formula (1), R ₁ represents a substituent other than a hydrogen atom or a hydroxyl group, and preferred substituents include an aliphatic group, an aromatic group, a heterocyclic group, an alkoxy group, an amino group, and an aryloxy group. , Cyano group, nitro group, halogen atom, carboxyl group and the like. Preferred examples of the aliphatic group represented by R ₁ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a tert-butyl group, an n-octyl group, an n-decyl group, an eicosyl group, Examples include 2-chloroethyl group, 2-cyanoethyl group, 2-ethylhexyl group, vinyl group, allyl group, ethynyl group, (4-dimethylamino-phenyl) -vinyl group, and among these, methyl group is preferable. Ethyl group, vinyl group, allyl group, n-octyl group, and n-decyl group. Preferred examples of the aromatic group represented by R ₁ include a phenyl group, p-tolyl group, naphthyl group, m-chlorophenyl group, 4-dimethylaminophenyl group, o-hexadecanoylaminophenyl group, and the like. Among them, the preferred position is a phenyl group. Preferred examples of the heterocyclic group represented by R ₁ include a pyridyl group, a thiazolyl group, a 2-benzothiazolyl group, an oxazolyl group, an imidazolyl group, a 2-furyl group, a 2-thienyl group, a pyrrolyl group, and a pyrazinyl group. 2-pyrimidinyl group, pyridazinyl group, selenazolyl group, sulfolanyl group, piperidinyl group, pyrazolyl group, tetrazolyl group, 2- (5-dimethylamino) thienyl group, 2- (5-dimethylamino) furyl group, 2- [5 -(4-dimethylamino) -phenyl] thienyl group, 2- [5- (4-dimethylamino) -phenyl] furyl group, 2- [5- (4-dimethylamino-phenyl) -vinyl] thienyl group, 2 -[5- (4-dimethylamino-phenyl) -vinyl] furyl group and the like are mentioned, and among these, preferred is pyri Group, 2-furyl group, 2-thienyl group, a pyrrolyl group. Preferred examples of the alkoxy group represented by R ₁ include a methoxy group, an ethoxy group, a tert-butoxy group, and a 2-chloroethoxy group. Among these, a methoxy group and an ethoxy group are preferred. It is a group. Preferred amino groups for the substituent represented by R ₁ include, for example, methylamino group, dimethylamino group, diethylamino group, ethylmethylamino group, ethylbutylamino group, diphenylamino group, pyrrolidyl group, piperidyl group, ethyloctyl group. An amino group, a dioctylamino group, a didodecylamino group, a dodecyloctylamino group, a viololidium group, etc. are mentioned. Among these, a dimethylamino group, a diethylamino group, an ethylbutylamino group, a pyrrolidyl group, an ethyloctylamino group are preferable. Group, a dioctylamino group. Preferred examples of the aryloxy group represented by R ₁ include a phenoxy group and a naphthyloxy group, and among these, a phenoxy group is preferable. Examples of the halogen atom preferable as the substituent represented by R ₁ include an iodine atom, a bromine atom, a chlorine atom, and a fluorine atom.

In the general formula (1), Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, and examples of the formed aromatic carbocycle include a phenyl group and naphthyl. Examples of the heterocyclic ring formed include a furan ring, a thiophene ring, a pyridine ring, an indole ring, a quinoline ring, a pyrrole ring, a carbazole ring, a julolidine ring, an imidazole ring, a benzofuran ring, and a benzothiophene. Ring, tetrahydroquinoline ring, and among them, a phenyl ring, a furan ring, a thiophene ring, a pyrrole ring, and a julolidine ring, which may have a substituent, are represented by Z _1. that examples of the atomic group substituent which may have needed to form an aromatic carbocyclic or heterocyclic ring, include the examples given in R _1, these Chide preferred are dimethylamino group, diethoxy amino group, an ethyl butylamino group, a pyrrolidyl group, an ethyl octyl amino group, a dioctylamino group.

In the general formula (1), L is a methine chain of 1 to 5 that forms a conjugated chain, and has a divalent aromatic ring group or heterocyclic group as a linking group at the end or in the middle. May be. Examples of the divalent aromatic ring group and heterocyclic ring group that may be present as the linking group include those exemplified for R ₁ .

<< Heterocyclic Compound Represented by General Formula (2) >>
In the general formula (2), group of atoms represented by Z ₁ has the same meaning as Z ₁ in the general formula (1).

  In the general formula (2), L is synonymous with L in the general formula (1).

In the general formula (2), X ₁ represents O, NR ₈ or S, R ₈ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group, and the aliphatic group or aromatic group represented by R ₈ Examples of the group and heterocyclic group include the same groups as those described for R ₁ .

<< Heterocyclic Compound Represented by General Formula (3) >>
In Formula (3), the group represented by R ₁ has the same meaning as R ₁ in the general formula (1).

In the general formula (3), R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom or a substituent, and preferred substituents include an aliphatic group, an aromatic group, a heterocyclic group, an alkoxy group, and an amino group. , Aryloxy group, cyano group, nitro group, halogen atom, hydroxyl group, carboxyl group. Examples of the aliphatic group, aromatic group, heterocyclic group, alkoxy group, amino group, aryloxy group, and halogen atom represented by R ₂ , R ₃ , and R ₄ are the same as the examples given for R ₁ . R ₂ and R ₃ , R ₃ and R ₄ , and R ₂ and R ₄ may form a ring. Examples of the ring formed include a cyclohexene ring, a cyclopentene ring, a benzene ring, and naphthalene. A ring etc. are mentioned. When n1 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other, and form a ring between R ₂ and R ₂ or R ₃ and R _{3 in} the adjacent repeating unit. May be.

In the general formula (3), group of atoms represented by Z ₁ has the same meaning as Z ₁ in the general formula (1).

In the general formula (3), n1 represents 0, 1 or 2, and when n1 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other.

<< Heterocyclic Compound Represented by General Formula (4) >>
In the general formula (4), the group represented by R ₁ has the same meaning as R ₁ in the general formula (1).

In the general formula (4), R ₂ , R ₅ and R ₆ each independently represent a hydrogen atom or a substituent, and preferred substituents include an aliphatic group, an aromatic group, a heterocyclic group, an alkoxy group and an amino group. An aryloxy group, a cyano group, a nitro group, a halogen atom, a hydroxyl group, a carboxyl group, and an aliphatic group, an aromatic group, a heterocyclic group, an alkoxy group, an amino group represented by R ₂ , R ₅ , or R ₆ Examples of the group, the aryloxy group and the halogen atom include the same groups as mentioned for R ₁ .

In the general formula (4), group of atoms represented by Z ₁ has the same meaning as Z ₁ in the general formula (1), Z ₂ represents an aromatic carbocyclic or heterocyclic ring, represented by Z ₂ Examples of the aromatic carbocycle include a phenyl group, a naphthyl group, and an anthracenyl group. Examples of the heterocyclic ring represented by Z ₂ include a furan ring, a thiophene ring, a pyridine ring, an indole ring, a quinoline ring, and a pyrrole. A ring and a carbazole ring. Among these, a phenyl ring, a furan ring, a thiophene ring and a pyrrole ring are preferable, and these may have a substituent.

  In the general formula (4), m1 represents 1 or 2, and p1 represents 0 or 1.

<< Heterocyclic Compound Represented by General Formula (5) >>
In Formula (5), the group represented by R _2, R _3, R ₄ has the same meaning as R _2, R _3, R ₄ in the formula (3).

In the general formula (5), group of atoms represented by Z ₁ has the same meaning as Z ₁ in the general formula (1), what is represented by X ₁ is synonymous with X ₁ in the general formula (2) N2 represents 0, 1 or 2, and when n2 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other.

<< Heterocyclic Compound Represented by General Formula (6) >>
In Formula (6), the group represented by R _2, R _5, R ₆ has the same meaning as R _2, R _5, R ₆ in the general formula (4).

In the general formula (6), group of atoms represented by Z ₁ has the same meaning as Z ₁ in the general formula (1), the same meaning as Z ₂ in the general formula (4) is to be represented by Z ₂ , and the the represented by X ₁ has the same meaning as X ₁ in the general formula (2).

  In the general formula (6), m2 represents 1 or 2, and p2 represents 0 or 1.

<< Heterocyclic Compound Represented by General Formula (7) >>
In the general formula (7), R ₉ , R ₁₀ and R ₁₁ each independently represent a hydrogen atom or a substituent, and preferred substituents include an aliphatic group, an aromatic group, a heterocyclic group, an alkoxy group, An amino group, an aryloxy group, a cyano group, a nitro group, a halogen atom, a hydroxyl group, a carboxyl group, and an aliphatic group, aromatic group, heterocyclic group, alkoxy group represented by R ₂ , R ₅ , R ₆ Examples of the amino group, aryloxy group and halogen atom include the same examples as those described for R ₁ .

In the general formula (7), R ₁₂ and R ₁₃ each represent an aliphatic group, an aromatic group, or a heterocyclic group, and examples of preferred aliphatic group, aromatic group, and heterocyclic group are those described for R ₁ . An example similar to is given. R ₁₀ and R ₁₃ , R ₁₁ and R ₁₂ , and R ₁₂ and R ₁₃ may form a ring, and examples of the ring formed include a pipedidine ring, a pyrrolidine ring, a pyridine ring, and a tetrahydropyridine ring. It is done. A heterocyclic ring and a condensed ring are formed at the position of *.

  Hereinafter, although the specific example of the heterocyclic compound represented by the said General formula (1)-(7) which concerns on this invention is shown, this invention is not limited to these.

  Below, an example of the synthesis example of the heterocyclic compound represented by said general formula (1)-(7) which concerns on this invention is shown.

<< Synthesis of Exemplified Compound II-1 >>
Exemplified compound I-1 was synthesized according to the synthesis route described below.

  Into a 300 ml three-headed flask, 18.8 g of intermediate 1, 18.0 g of intermediate 2, 150 ml of toluene and 9.6 g of morpholine were added and refluxed for 3 hours. Thereafter, the mixture was allowed to cool, and toluene was distilled off under reduced pressure. This residue was separated by a silica gel column (developing solvent: ethyl acetate) to obtain 14.5 g of Example Compound II-1 which was the target product.

<< Sensitivity treatment of semiconductor for photoelectric conversion material >>
The semiconductor for photoelectric conversion materials of the present invention is sensitized by including any one of the heterocyclic compounds represented by the general formulas (1) to (7), and exhibits the effects described in the present invention. It becomes possible. Here, including the heterocyclic compound according to the present invention means that the heterocyclic compound according to the present invention is included in the porous structure of the semiconductor when the semiconductor has a porous structure such as adsorption to the semiconductor surface. There are various modes such as entering.

The total content of each of the heterocyclic compounds according to the present invention represented by the general formulas (1) to (7) per 1 m ² of the semiconductor layer (which may be a semiconductor) is in the range of 0.01 mmol to 100 mmol. Is preferable, more preferably 0.1 mmol to 50 mmol, and particularly preferably 0.5 mmol to 20 mmol.

  When sensitizing treatment is performed using any one of the heterocyclic compounds represented by the general formulas (1) to (7) according to the present invention, the heterocyclic compound may be used alone or in combination. In addition, any one of the heterocyclic compounds represented by the general formulas (1) to (7) according to the present invention and other compounds (for example, U.S. Pat. No. 4,684) may be used. No. 5,537, No. 4,927,721, No. 5,084,365, No. 5,350,644, No. 5,463,057, It is also possible to use a mixture of each of the specifications such as US Pat. No. 5,525,440 and the compounds described in JP-A-7-249790, JP-A-2000-150007 and the like.

  In particular, when the application of the semiconductor for a photoelectric conversion material of the present invention is a solar cell described later, two types having different absorption wavelengths are used so that the wavelength range of photoelectric conversion can be made as wide as possible to effectively use sunlight. It is preferable to use a mixture of the above dyes.

  In order to include any one of the heterocyclic compounds represented by the general formulas (1) to (7) in the semiconductor, the heterocyclic compound is dissolved in an appropriate solvent (such as ethanol), and the solution is dissolved in the solution. A method of immersing a well-dried semiconductor for a long time is common.

  When producing a semiconductor for a photoelectric conversion material using a combination of any one of the heterocyclic compounds represented by the general formulas (1) to (7) or a combination of other sensitizing dye compounds. Alternatively, a mixed solution of each heterocyclic compound may be prepared and used. Alternatively, a solution may be prepared for each heterocyclic compound and immersed in each solution in order. When preparing a separate solution for each heterocyclic compound and immersing it in each solution in order, this is the case regardless of the order in which the heterocyclic compound or sensitizing dye according to the present invention is included in the semiconductor. The effects described in the invention can be obtained. Moreover, you may produce by mixing the semiconductor fine particle which adsorb | sucked the heterocyclic compound based on this invention independently.

  The adsorption treatment may be performed when the semiconductor is in the form of particles, or may be performed after forming a film on the support. The solution in which the compound used for the adsorption treatment is dissolved may be used at room temperature, or may be used by heating in a temperature range in which the heterocyclic compound according to the present invention does not decompose and the solution does not boil. Moreover, you may implement the adsorption | suction of the heterocyclic compound based on this invention after application | coating of semiconductor fine particles (after formation of a photosensitive layer) like manufacture of the photoelectric conversion element mentioned later. Further, the adsorption of the heterocyclic compound according to the present invention may be carried out by simultaneously applying the semiconductor fine particles and the heterocyclic compound according to the present invention. Unadsorbed compounds can be removed by washing.

  Moreover, about the sensitization process of the semiconductor for photoelectric conversion materials of this invention, a sensitization process is carried out by including any 1 type of heterocyclic compound represented by said general formula (1)-(7) about a semiconductor. Although performed, details of the sensitization process will be specifically described in the photoelectric conversion element described later.

  Further, in the case of a semiconductor for a photoelectric conversion material having a semiconductor thin film with a high porosity, before water is adsorbed on the semiconductor thin film and in the voids inside the semiconductor thin film by moisture, water vapor, etc., the complex according to the present invention is provided. It is preferable to complete the adsorption treatment (sensitization treatment of a semiconductor for a photoelectric conversion material) such as a ring compound or a sensitizing dye compound.

  You may surface-treat the semiconductor for photoelectric conversion materials of this invention using an organic base. Examples of the organic base include diarylamine, triarylamine, pyridine, 4-t-butylpyridine, polyvinylpyridine, quinoline, piperidine, amidine, and the like. Among them, pyridine, 4-t-butylpyridine, polyvinyl Pyridine is preferred.

  If the organic base is a liquid, it is left as it is, and if it is a solid, a solution dissolved in an organic solvent is prepared, and the semiconductor for photoelectric conversion material of the present invention is immersed in a liquid amine or an amine solution to perform surface treatment. Can be implemented.

  Further, as a dye that can be used in combination with any one of the heterocyclic compounds represented by the general formulas (1) to (7) according to the present invention, the semiconductor according to the present invention is spectrally sensitized. Any dye can be used if possible. In order to make the wavelength range of photoelectric conversion as wide as possible and increase the conversion efficiency, it is preferable to mix two or more kinds of dyes. Moreover, the pigment | dye to mix and its ratio can be selected so that it may match with the wavelength range and intensity distribution of the target light source.

  Examples of the dye that can be used in combination with the heterocyclic compound according to the present invention include metal complex dyes, phthalocyanine dyes, porphyrin dyes from a comprehensive viewpoint such as photoelectron transfer reaction activity, photo durability, and photochemical stability. Dyes and polymethine dyes are preferably used.

  Among the metal complex dyes, JP-A Nos. 2001-223037, 2001-226607, US Pat. Nos. 4,927,721, 4,684,537, 5,084,365, 5,350,644, 5,463,057, 5,525,440, JP-A-7-249750, JP 10-504512, World Patent 989/50393, etc. Ruthenium complex dyes are preferably used.

  Examples of the porphyrin dye and the phthalocyanine dye include dyes described in JP-A No. 2001-223037 as preferable dyes.

  Examples of the polymethine dye include conventionally known methine dyes, JP-A Nos. 11-35836, 11-158395, 11-163378, 11-214730, and 11-214731. 10-093118, 11-273754, JP-A-2000-106224, 2000-357809, 2001-052766, EP 892,411, 911,841, etc. Those described are mentioned.

<< Method for Manufacturing Semiconductor for Photoelectric Conversion Material >>
A method for manufacturing a semiconductor for a photoelectric conversion material of the present invention will be described.

  As one embodiment of the semiconductor for a photoelectric conversion material of the present invention, a method such as forming the above semiconductor for a photoelectric conversion material on a conductive support by firing is exemplified.

  When the semiconductor for a photoelectric conversion material of the present invention is produced by firing, the semiconductor sensitization (adsorption, penetration into a porous body, etc.) treatment using the heterocyclic compound or sensitizing dye according to the present invention is performed. It is preferable to carry out after firing. It is particularly preferable to perform the compound adsorption treatment quickly after the firing and before the water is adsorbed to the semiconductor.

  When the semiconductor for photoelectric conversion materials of the present invention is in the form of particles, the semiconductor electrode is preferably prepared by applying or spraying the semiconductor for photoelectric conversion materials onto a conductive support. Moreover, when the semiconductor for photoelectric conversion materials of this invention is a film | membrane form, Comprising: It is not hold | maintained on an electroconductive support body, the semiconductor electrode for photoelectric conversion materials is bonded on an electroconductive support body, and a semiconductor electrode is attached. It is preferable to produce it.

  Hereinafter, a process for producing a semiconductor for a photoelectric conversion material of the present invention will be specifically described.

<< Preparation of coating liquid containing semiconductor fine powder >>
First, a coating solution containing fine semiconductor powder is prepared. The semiconductor fine powder preferably has a finer primary particle diameter, and the primary particle diameter is preferably 1 nm to 5000 nm, and more preferably 2 nm to 50 nm. The coating liquid containing the semiconductor fine powder can be prepared by dispersing the semiconductor fine powder in a solvent. The semiconductor fine powder dispersed in the solvent is dispersed in the form of primary particles. The solvent is not particularly limited as long as it can disperse the semiconductor fine powder.

  Examples of the solvent include water, an organic solvent, and a mixed solution of water and an organic solvent. As the organic solvent, alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone, acetone and acetyl acetone, hydrocarbons such as hexane and cyclohexane, and the like are used. A surfactant and a viscosity modifier (polyhydric alcohol such as polyethylene glycol) can be added to the coating solution as necessary. The range of the semiconductor fine powder concentration in the solvent is preferably 0.1 to 70% by mass, more preferably 0.1 to 30% by mass.

<< Application of Semiconductor Fine Powder-Containing Coating Liquid and Firing Process of Formed Semiconductor Layer >>
The semiconductor fine powder-containing coating solution obtained as described above is applied or sprayed onto a conductive support, dried, etc., and then baked in air or an inert gas to provide a conductive support. A semiconductor layer (semiconductor film) is formed thereon.

  The film obtained by applying and drying the coating liquid on the conductive support is composed of an aggregate of semiconductor fine particles, and the particle size of the fine particles corresponds to the primary particle size of the semiconductor fine powder used. is there.

  The semiconductor fine particle aggregate film formed on the substrate such as the conductive support in this way has a low bonding strength with the conductive support and a bonding strength between the fine particles and a low mechanical strength. From the above, the semiconductor fine particle aggregate film is preferably fired to increase the mechanical strength and to obtain a fired product film firmly fixed to the substrate.

  In the present invention, the fired product film may have any structure, but is preferably a porous structure film (also referred to as a porous layer having voids).

  Here, the porosity of the semiconductor thin film according to the present invention is preferably 10% by volume or less, more preferably 8% by volume or less, and particularly preferably 0.01% by volume to 5% by volume. The porosity of the semiconductor thin film means a porosity that is penetrable in the thickness direction of the dielectric, and can be measured using a commercially available apparatus such as a mercury porosimeter (Shimadzu Polarizer 9220 type).

  The film thickness of the semiconductor layer that is a fired product film having a porous structure is preferably at least 10 nm or more, more preferably 100 nm to 10,000 nm.

  From the viewpoint of appropriately adjusting the actual surface area of the fired product film during the firing treatment and obtaining a fired product film having the above porosity, the firing temperature is preferably lower than 1000 ° C, more preferably 200 ° C to 800 ° C. It is the range of 300 degreeC, Most preferably, it is the range of 300 to 800 degreeC.

  Further, the ratio of the actual surface area to the apparent surface area can be controlled by the particle diameter and specific surface area of the semiconductor fine particles, the firing temperature, and the like. In addition, after heat treatment, for example, chemical plating or aqueous trichloride using a titanium tetrachloride aqueous solution is used to increase the surface area of the semiconductor particles, increase the purity in the vicinity of the semiconductor particles, and increase the efficiency of electron injection from the dye into the semiconductor particles. Electrochemical plating using a titanium aqueous solution may be performed.

<Semiconductor sensitization processing>
As described above, the semiconductor sensitization treatment is performed by dissolving the dye in an appropriate solvent and immersing the substrate obtained by firing the semiconductor in the solution. In that case, a substrate on which a semiconductor layer (also referred to as a semiconductor film) is formed by baking is subjected to pressure reduction treatment or heat treatment in advance to remove bubbles in the film, and the general formula (1) according to the present invention. It is preferable that any one of the heterocyclic compounds of (6) can enter deep inside the semiconductor layer (semiconductor film), particularly when the semiconductor layer (semiconductor film) is a porous structure film. preferable.

"solvent"
The solvent used to dissolve the heterocyclic compound of any one of the general formulas (1) to (7) according to the present invention can dissolve the heterocyclic compound according to the present invention, and the semiconductor. There is no particular limitation as long as it does not dissolve or react with the semiconductor, but moisture and gas dissolved in the solvent enter the semiconductor film and adsorb the heterocyclic compound according to the present invention. In order to prevent hindering the sensitization treatment, it is preferable to deaerate and purify in advance.

  In the dissolution of the heterocyclic compound according to the present invention, preferably used solvents are alcohol solvents such as methanol, ethanol and n-propanol, ketone solvents such as acetone and methyl ethyl ketone, diethyl ether, diisopropyl ether, tetrahydrofuran, 1,4- Ether solvents such as dioxane and halogenated hydrocarbon solvents such as methylene chloride and 1,1,2-trichloroethane, particularly preferably methanol, ethanol, acetone, methyl ethyl ketone, tetrahydrofuran and methylene chloride.

《Tensing temperature and time》
The time for immersing the substrate on which the semiconductor is baked in the solution containing any one heterocyclic compound of the general formulas (1) to (7) according to the present invention depends on the semiconductor layer (semiconductor film) according to the present invention. The heterocyclic compound penetrates deeply to sufficiently advance adsorption, etc., sufficiently sensitizes the semiconductor, and is generated by decomposition of the heterocyclic compound according to the present invention in solution and the decomposition product adsorbs the compound. From the viewpoint of suppressing the hindrance, it is preferably 3 to 48 hours, more preferably 4 to 24 hours under 25 ° C conditions. This effect is particularly remarkable when the semiconductor film is a porous structure film. However, the immersion time is a value under the condition of 25 ° C., and is not limited to the above when the temperature condition is changed.

  When immersed, the solution containing any one of the heterocyclic compounds of the general formulas (1) to (7) according to the present invention is a temperature at which it does not boil unless the heterocyclic compound according to the present invention is decomposed. It may be used after being heated. The preferred temperature range is 10 to 100 ° C., more preferably 25 to 80 ° C., but this is not the case when the solvent boils in the temperature range as described above.

<< Photoelectric conversion element >>
The photoelectric conversion element of this invention is demonstrated using FIG.

  FIG. 1 is a partial cross-sectional view showing an example of the structure of the photoelectric conversion element of the present invention.

  Reference numeral 1 denotes a conductive support, 2 denotes a photosensitive layer, 3 denotes a charge transfer layer, and 4 denotes a counter electrode. The conductive support 1 and the photosensitive layer 2 are also collectively referred to as a semiconductor electrode.

  Here, the photosensitive layer 2 is a layer having the semiconductor for a photoelectric conversion material of the present invention, and the charge transfer layer 3 usually contains a redox electrolyte and is in contact with the conductive support 1, the photosensitive layer 2, and the counter electrode 4. Used in the form.

<< Method for Manufacturing Photoelectric Conversion Element >>
The manufacturing method of a photoelectric conversion element is demonstrated using FIG.

  The photoelectric conversion element of the present invention is represented by the general formulas (1) to (7) according to the present invention after forming a semiconductor thin film as described above on a conductive support 1 as shown in FIG. It is produced through a process of adsorbing any one kind of heterocyclic compound.

  In addition, the surface area of the semiconductor thin film is increased, impurities on the surface of the semiconductor thin film are removed to increase the purity of the semiconductor, and any one of the heterocyclic compounds represented by the general formulas (1) to (7) For example, chemical plating using a titanium tetrachloride aqueous solution or electrochemical plating using a titanium trichloride aqueous solution may be performed for the purpose of increasing the efficiency of electron injection from the semiconductor to the semiconductor.

  The semiconductor film formed on the conductive support 1 is adsorbed with any one of the heterocyclic compounds represented by the above general formulas (1) to (7), and the semiconductor film is sensitized for photosensitivity. Layer 2 is formed. As described above, the sensitizing treatment method is performed by dissolving the heterocyclic compound according to the present invention in an appropriate solvent and immersing the semiconductor film formed on the conductive support 1 in the solution. In that case, the semiconductor film is subjected to pressure reduction treatment or heat treatment beforehand to remove bubbles in the film, and any one of the heterocyclic compounds represented by the general formulas (1) to (7) is obtained. It is preferable to be able to enter deep inside the semiconductor film.

  When any one of the heterocyclic compounds represented by the general formulas (1) to (7) is adsorbed to the semiconductor according to the present invention, it may be used alone or in combination. Good. Furthermore, conventionally known sensitizing dye compounds (for example, U.S. Pat. Nos. 4,684,537, 4,927,721, 5,084,365, 5,350,644, No. 5,463,057, 5,525,440, JP-A-7-249790, JP-A-2000-150007, etc.) may be mixed and adsorbed.

  In particular, when the application of the semiconductor is a solar cell, it is preferable to use a mixture of two or more dyes so that the wavelength range of photoelectric conversion can be widened and sunlight can be used as effectively as possible.

  The semiconductor for photoelectric conversion material sensitized by using a plurality of types of any one of the heterocyclic compounds represented by the general formulas (1) to (7) according to the present invention in combination is a heterocycle according to the present invention used in combination. It may be prepared by immersing in a solution prepared by mixing compounds, or by preparing a solution for each heterocyclic compound and immersing in each solution in turn.

  When preparing different solutions for each heterocyclic compound and immersing them in each solution in order, the effect of the present invention regardless of the order in which the semiconductor or a conventionally known sensitizing dye is adsorbed Can be obtained.

  The adsorption treatment may be performed using a solution in which the heterocyclic compound according to the present invention is dissolved at room temperature, or by heating the solution to a temperature that does not affect the heterocyclic compound according to the present invention. good. Furthermore, it is preferable to remove the dye that has not been adsorbed during the adsorption treatment by washing treatment with a solvent or the like.

  After the dye is adsorbed to the semiconductor film formed on the conductive support 1 to form the photosensitive layer 2, the counter electrode 4 is disposed so as to face the photosensitive layer 2. Further, a redox electrolyte as a charge transfer layer is injected between the semiconductor electrode and the counter electrode 4 to obtain a photoelectric conversion element.

《Solar cell》
The solar cell of the present invention will be described.

  As shown in FIG. 1, the solar cell of the present invention is optimally designed for sunlight and circuit design as one aspect of the photoelectric conversion element of the present invention, and is optimal when sunlight is used as a light source. It has a structure in which photoelectric conversion is performed. That is, the semiconductor for photoelectric conversion material has a structure that can be irradiated with sunlight. When constituting the solar cell of the present invention, it is preferable that the semiconductor electrode, the charge transfer layer and the counter electrode are housed in a case and sealed, or the whole is sealed with resin.

  When the solar cell of the present invention is irradiated with sunlight or an electromagnetic wave equivalent to sunlight, the compound of the present invention adsorbed on the semiconductor for photoelectric conversion material absorbs the irradiated light or electromagnetic wave and excites it. Electrons generated by excitation move to the semiconductor, and then move to the counter electrode 4 via the conductive support 1 to reduce the redox electrolyte of the charge transfer layer 3. On the other hand, the compound of the present invention in which electrons are transferred to a semiconductor is an oxidant, but is reduced by the supply of electrons from the counter electrode 4 via the redox electrolyte of the charge transfer layer 3 and is reduced to the original. At the same time, the redox electrolyte of the charge transfer layer 3 is oxidized and returned to a state where it can be reduced again by the electrons supplied from the counter electrode 4. In this way, electrons flow, and a solar cell using the photoelectric conversion element of the present invention can be configured.

<Conductive support>
The conductive support used in the photoelectric conversion element of the present invention and the solar battery of the present invention is provided with a conductive material such as a conductive material such as a metal plate or a non-conductive material such as a glass plate or a plastic film. A structure having a different structure can be used. Examples of materials used for the conductive support include metals (for example, platinum, gold, silver, copper, aluminum, rhodium, indium) or conductive metal oxides (for example, indium-tin composite oxide, fluorine for tin oxide) And carbon). The thickness of the conductive support is not particularly limited, but is preferably 0.3 to 5 mm.

  The conductive support is preferably substantially transparent. Substantially transparent means that the light transmittance is 10% or more, preferably 50% or more, and 80 % Or more is more preferable. In order to obtain a transparent conductive support, it is preferable to provide a conductive layer made of a conductive metal oxide on the surface of a glass plate or a plastic film. When the transparent conductive support 1 is used, light is preferably incident from the support side.

The conductive support has a surface resistance of preferably 50 Ω / cm ² or less, and more preferably 10 Ω / cm ² or less.

《Charge transfer layer》
The charge transfer layer used in the present invention will be described.

A redox electrolyte is preferably used for the charge transfer layer. Here, examples of the redox electrolyte include I ⁻ / I ₃ ⁻ system, Br ⁻ / Br ₃ ⁻ system, and quinone / hydroquinone system. Such a redox electrolyte can be obtained by a conventionally known method. For example, an I ⁻ / I ₃ ⁻ based electrolyte can be obtained by mixing iodine ammonium salt and iodine. The charge transfer layer is composed of dispersions of these redox electrolytes. These dispersions are liquid electrolytes when they are in solution, and are dispersed in solid polymer electrolytes and gel substances when dispersed in polymers that are solid at room temperature. When called, it is called a gel electrolyte. When a liquid electrolyte is used as the charge transfer layer, an electrochemically inert solvent is used as the solvent, for example, acetonitrile, propylene carbonate, ethylene carbonate, or the like is used. Examples of the solid polymer electrolyte include the electrolyte described in JP-A No. 2001-160427, and examples of the gel electrolyte include the electrolyte described in “Science Science” Vol. 21, No. 5, pages 288 to 293. .

《Counter electrode》
The counter electrode used in the present invention will be described.

Counter electrode, as long as it has conductivity, but any conductive material is used, I ₃ ^- catalytic ability to perform fast enough the reduction reaction of oxidation and other redox ions such as ions It is preferable to use what you have. Examples of such a material include a platinum electrode, a surface of a conductive material subjected to platinum plating or platinum deposition, rhodium metal, ruthenium metal, ruthenium oxide, and carbon.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Example 1
<< Production of photoelectric conversion element >>
[Production of Photoelectric Conversion Element 1]
A photoelectric conversion device as shown in FIG. 1 was produced as described below.

  62.5 ml of titanium tetraisopropoxide (first grade manufactured by Wako Pure Chemical Industries, Ltd.) was dropped into 375 ml of pure water at room temperature with vigorous stirring for 10 minutes (a white precipitate was formed), and then 70% After 2.65 ml of nitric acid was added and the reaction system was heated to 80 ° C., stirring was continued for 8 hours. Further, the reaction mixture was concentrated under reduced pressure until the volume of the reaction mixture became about 200 ml, and then 125 ml of pure water and 140 g of titanium oxide powder (Super Titania F-6 manufactured by Showa Titanium Co., Ltd.) were added thereto to obtain a titanium oxide suspension (about 800 ml). ) Was prepared. The titanium oxide suspension is applied onto a transparent conductive glass plate coated with fluorine-doped tin oxide, dried naturally and then fired at 300 ° C. for 60 minutes to form a film-like titanium oxide on the support. did.

  Next, a solution in which 5 g of Exemplified Compound I-1 was dissolved in 200 ml of methanol solution was prepared, the above-mentioned film-like titanium oxide (semiconductor layer for photoelectric conversion material) was immersed together with 1 g of trifluoroacetic acid, and 2 Ultrasonic irradiation for hours. After the reaction, the film-like titanium oxide (semiconductor layer for photoelectric conversion material) was washed with chloroform and vacuum dried to prepare a photosensitive layer 2 (semiconductor for photoelectric conversion material).

  As the counter electrode 4, a transparent conductive glass plate coated with fluorine-doped tin oxide and further carrying platinum thereon is used, and the volume ratio is between the conductive support 1 and the counter electrode 4. A redox electrolyte prepared by dissolving tetrapropylammonium iodide and iodine in a 1: 4 mixed solvent of acetonitrile / ethylene carbonate so that the respective concentrations are 0.46 mol / liter and 0.06 mol / liter. The charged charge transfer layer 3 was produced, and the photoelectric conversion element 1 was produced.

[Preparation of Photoelectric Conversion Elements 2 to 24: Present Invention]
In the production of the photoelectric conversion element 1, photoelectric conversion elements 2 to 24 were obtained in the same manner except that the exemplified compound I-1 was changed to the compounds shown in Table 1.

[Production of Photoelectric Conversion Elements RA and RB: Comparative Example]
Photoelectric conversion elements RA and RB were obtained in the same manner as in the production of the photoelectric conversion element 1 except that the comparative compounds RA and RB shown in Table 1 were changed.

<< Production of solar cells >>
[Production of Solar Cells SC-01 to SC-24: Present Invention]
After enclosing the side surface of the photoelectric conversion element 1 with a resin, lead wires were attached, and three solar cells SC-01 to SC-24 of the present invention were produced.

[Production of Solar Cells SC-RA and SC-RB: Comparative Example]
In the production of the solar cell SC-01, three lots of the solar cells SC-RA and SC-RB were produced in the same manner except that the comparative photoelectric conversion elements RA and RB were used.

<< Evaluation of photoelectric conversion characteristics of solar cells >>
Each of solar cells SC-01 to SC-24 and solar cells SC-RA and SC-RB obtained above was 100 mW by solar simulator (JASCO (JASCO) low energy spectral sensitivity measuring device CEP-25). The short-circuit current density Jsc (mA / cm ² ) and the open-circuit voltage value Voc (V) when irradiated with light having an intensity of / m ² were measured, and the obtained results are shown in Table 1. The indicated value was the average value of the measurement results for three solar cells having the same configuration and production method.

As is clear from the results in Table 1, the solar cell of the present invention exhibits high photoelectric conversion characteristics with respect to the comparative example, and is any one of the general formulas (1) to (7) according to the present invention. It turns out that it is effective to use a heterocyclic compound. Further, it is clear that the solar cells SC-01 to SC-24 of the present invention are excellent in stability because no decrease in photoelectric conversion efficiency is observed even after 100 hours of light irradiation of 100 mW / m ² by a solar simulator. Became.

It is a fragmentary sectional view which shows an example of the structure of the photoelectric conversion element of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conductive support body 2 Photosensitive layer 3 Charge transfer layer 4 Counter electrode

Claims (7)

The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (1) or General formula (2).

[In the formula, R ₁ represents a substituent other than a hydrogen atom or a hydroxy group, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, and L represents a conjugated chain. 5 methine chains, which may have a divalent aromatic ring group or heterocyclic group as a linking group at the terminal or in the middle. ]

[In the formula, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, L is 1 to 5 methine chains forming a conjugated chain, It may have a divalent aromatic ring group or heterocyclic group, X ₁ represents O, NR ₈ or S, and R ₈ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group. . ] The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (3) or General formula (4).

[Wherein R ₁ represents a hydrogen atom or a substituent other than a hydroxy group, R ₂ , R ₃ and R ₄ each independently represents a hydrogen atom or a substituent, and R ₂ and R ₃ , R ₃ And R ₄ , R ₂ and R ₄ may each form a ring, Z ₁ represents an atomic group necessary to form an aromatic carbocycle or a heterocycle, n1 represents 0, 1 or 2 When n1 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other, and in adjacent repeating units, a ring is formed between R ₂ and R ₂ or R ₃ and R _3. Also good. ]

[Wherein, R ₁ represents a substituent other than a hydrogen atom or a hydroxyl group, R ₂ , R ₅ and R ₆ each independently represents a hydrogen atom or a substituent, and Z ₁ represents an aromatic carbocyclic or heterocyclic ring. Z ₂ represents an aromatic carbocyclic or heterocyclic ring, m 1 represents 1 or 2, and p 1 represents 0 or 1. ] The semiconductor for photoelectric conversion materials characterized by including the heterocyclic compound represented by following General formula (5) or General formula (6).

[Wherein R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom or a substituent, and R ₂ and R ₃ , R ₃ and R ₄ , R ₂ and R ₄ each form a ring, Z ₁ represents an atomic group necessary for forming an aromatic carbocyclic or heterocyclic ring, X ₁ represents O, NR ₈ or S, and R ₈ represents a hydrogen atom, an aliphatic group or an aromatic group. Represents a group or a heterocyclic group, n2 represents 0, 1 or 2, and when n2 is 2, the substituents R ₂ and R ₃ of the repeating unit may be different from each other, and in the adjacent repeating unit, R ₂ And R ₂ , or R ₃ and R ₃ may form a ring. ]

[Wherein R ₂ , R ₅ and R ₆ each independently represents a hydrogen atom or a substituent, Z ₁ represents an atomic group necessary for forming an aromatic carbocycle or a heterocycle, and Z ₂ represents an aromatic X ₁ represents O, NR ₈ or S, R ₈ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group, m2 represents 1 or 2, p2 represents 0 or 1. ] A group of atoms necessary for forming the aromatic carbocycle or heterocycle represented by Z ₁ in the general formulas (1) to (6) is represented by the following general formula (7). The semiconductor for photoelectric conversion materials of any one of Claims 1-3.

[Wherein R ₉ , R ₁₀ and R ₁₁ each independently represents a hydrogen atom or a substituent, R ₁₂ and R ₁₃ each represents an aliphatic group, an aromatic group or a heterocyclic group, R ₁₀ and R ₁₃ , R ₁₁ and R ₁₂ , R ₁₂ and R ₁₃ may form a ring, and form a heterocyclic ring and a condensed ring at the position of *. ] It is a metal oxide semiconductor or a metal sulfide semiconductor, The semiconductor for photoelectric conversion materials of any one of Claims 1-4 characterized by the above-mentioned. The photoelectric conversion element semiconductor of any one of Claims 1-5 is provided on the electroconductive support body, The photoelectric conversion element characterized by the above-mentioned. A solar cell comprising the photoelectric conversion element according to claim 6, a charge transfer layer, and a counter electrode.

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