JP2009021116A - Photoelectric conversion element, and solar cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric conversion element having high efficiency, and to provide a solar cell using the same. <P>SOLUTION: A compound having a structure represented by general formula (1) is contained between counter electrodes. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photoelectric conversion element, and more particularly to a dye-sensitized photoelectric element and a solar cell using the same.

  In recent years, the use of sunlight, which is infinite and does not generate harmful substances, has been energetically studied. What is currently put into practical use as solar energy, which is a clean energy source, includes residential single crystal silicon, polycrystalline silicon, amorphous silicon, and inorganic solar cells such as cadmium telluride and indium copper selenide. .

  However, the disadvantages of these inorganic solar cells include, for example, that silicon is required to have a very high purity, and naturally, the purification process is complicated, the number of processes is large, and the manufacturing cost is high.

  On the other hand, many solar cells using organic materials have been proposed. As an organic solar cell, a Schottky photoelectric conversion element that joins a p-type organic semiconductor and a metal having a low work function, a p-type organic semiconductor and an n-type inorganic semiconductor, or a p-type organic semiconductor and an electron-accepting organic compound are joined. There are heterojunction photoelectric conversion elements and the like, and organic semiconductors used are synthetic dyes and pigments such as chlorophyll and perylene, conductive polymer materials such as polyacetylene, or composite materials thereof. These are thinned by a vacuum deposition method, a casting method, a dipping method, or the like to form a battery material. The organic material has advantages such as low cost and easy area enlargement, but there are many problems that the conversion efficiency is as low as 1% or less and the durability is poor.

  Under such circumstances, a solar cell exhibiting good characteristics has been reported by Dr. Gretzell of Switzerland (see Non-Patent Document 1). The proposed battery is a dye-sensitized solar cell, which is a wet solar cell using a titanium oxide porous thin film spectrally sensitized with a ruthenium complex as a working electrode. The advantage of this method is that it is not necessary to purify inexpensive metal compound semiconductors such as titanium oxide to high purity, and therefore, the light that is inexpensive and can be used extends over a wide visible light region. It is that light can be effectively converted into electricity.

  On the other hand, ruthenium complexes with limited resources are used, so when this solar cell is put to practical use, the supply of ruthenium complexes is in danger. In addition, the ruthenium complex is expensive and has problems with stability over time. If the ruthenium complex can be changed to an inexpensive and stable organic dye, this problem can be solved.

It is disclosed that when a compound having a triphenylamine structure is used as a dye of the battery, an element having high photoelectric conversion efficiency can be obtained (see Patent Document 1). However, it has been found that these dyes absorb only in the short wavelength region, have a low molar extinction coefficient, and have problems with durability.
JP 2005-123033 A Nature, 353, 737 (1991), B.R. O'Regan and M.M. Gratzel

  An object of the present invention is to provide a novel and highly durable sensitizing dye used for a sensitizing dye type photoelectric conversion element, to provide a highly efficient photoelectric conversion element and a solar cell using the same. is there.

  The above problem could be solved by the following configuration.

  1. A photoelectric conversion element comprising a compound having a structure represented by the following general formula (1) between opposing electrodes.

[Wherein R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom, a nitro group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a thioalkyl group, an amino group, which may be substituted. Represents an aryl group, a hydroxyl group, a carbonyl group, a thiol group, or a heterocyclic group. R _{1 to} R ₈ may form a cyclic structure or a condensed ring structure directly or via another bonding atom.
At least two or more of R _{1 to} R ₈ have a substituent other than hydrogen.
M represents two hydrogen atoms, or represents a divalent, trivalent, or tetravalent metal atom that may have an oxygen, halogen atom, or other ligand. ]
2. 2. The photoelectric conversion element as described in 1 above, wherein the compound having the structure of the general formula (1) contains an acidic group.

3. In the general formula (1), R _{1 to} R ₈ are compounds having at least one substituent having a bulky structure.

4). In the general formula (1), M is any one of Cu, Ni, Zn, Pd, VO, Co, Mg, and H _2. Conversion element.

  5). In the dye-sensitized photoelectric conversion element in which at least a semiconductor layer and an electrolyte layer are provided between the counter electrodes, a semiconductor layer and an electrolyte layer in which the compound having the structure of the general formula (1) is supported are provided. 5. The photoelectric conversion element as described in any one of 1 to 4 above, wherein the photoelectric conversion element is formed.

  6). 6. The photoelectric conversion element as described in any one of 1 to 5, wherein the semiconductor forming the semiconductor layer is titanium oxide.

  7. 6. The photoelectric conversion element as described in any one of 1 to 5, wherein the semiconductor forming the semiconductor layer is tin oxide.

  8). A solar cell comprising the photoelectric conversion element according to any one of 1 to 7 above.

  According to the present invention, a photoelectric conversion element and a solar cell having high conversion efficiency, stability, and durability can be provided.

  Hereinafter, the present invention will be described in more detail.

  The photoelectric conversion element of the present invention will be described with reference to the drawings.

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

  As shown in FIG. 1, it is comprised from the board | substrates 1, 1 ', the transparent conductive films 2 and 7, the metal compound semiconductor 3, the sensitizing dye 4, the electrolyte 5, and the partition 9.

  As a photoelectrode, a semiconductor layer having pores formed by sintering particles of a metal compound semiconductor 3 is provided on a substrate 1 (also referred to as a conductive support) to which a transparent conductive film 2 is attached. What adsorb | sucked the sensitizing dye 4 to the hole surface is used.

  As the counter electrode 6, a transparent conductive film 7 formed on a substrate 1 ′ and platinum 8 deposited thereon is used, and an electrolyte 5 is filled between both electrodes as an electrolyte layer.

  The present invention relates to a novel sensitizing dye used for this photoelectric conversion element.

  At the time of power generation, the sensitizing dye generates a current by repeating the photooxidation reaction, and a dye resistant to the oxidation reaction is required to improve durability.

  The compound represented by the general formula (1) (hereinafter also referred to as the sensitizing dye of the present invention) has excellent durability, a high molar extinction coefficient, and main absorption in a wide range of about 500 to 900 nm. Since the wavelength band can be controlled, light absorption in a long wavelength region can be performed, or arbitrary color control can be performed to design a cell with high designability.

  Below, the compound represented by the said General formula (1) is demonstrated.

In the general formula (1), examples of the halogen atom represented by R _{1 to} R ₈ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, A butyl group, an octyl group, a nonyl group, an octadecyl group, etc., an alkenyl group is, for example, a vinyl group, an allyl group, etc., an alkynyl group is, for example, an ethenyl group, and an alkoxy group is, for example, a methoxy group , An ethoxy group, a butoxy group, and the like. Examples of the alkylthio group include a methylthio group, an ethylthio group, and an octylthio group. Examples of the amino group include a methylamino group, an ethylamino group, and a dimethylamino group. Examples of the group include a phenyl group and a naphthyl group, and include a hydroxyl group, a carbonyl group, a thiol group, and a heterocyclic group. Te, for example, may be mentioned nitrogen, sulfur, a 3-8 membered heterocyclic ring containing oxygen or the like. These groups may further have a substituent. R _{1 to} R ₈ may form a cyclic structure or a condensed ring structure directly or via another bonding atom.

In the present invention, R _{1 to} R ₈ are preferably compounds having at least one substituent having a bulky structure. The bulky structure is, for example, a group having 4 or more carbon atoms, and further branched. An alkyl group is preferable, for example, t-butyl group, t-pentyl group, i-pentyl group, hexyl group, cyclohexyl group, octyl group, t-octyl group, nonyl group, phenyl group, naphthyl group, tolyl group. And octylphenyl group.

  Specific examples of the compound represented by the general formula (1) are shown below, but the present invention is not limited to these compounds.

  The sensitizing dye represented by the general formula (1) of the present invention can be prepared by a general synthesis method.

  For example, a tetraazaporphyrin derivative containing an acidic group can be synthesized using derivatives such as maleonitrile, fumaronitrile, orthodicyanobenzene containing an acidic group. Alternatively, a tetraazaporphyrin derivative can be synthesized using a derivative such as maleonitrile, fumaronitrile, or orthodicyanobenzene having a functional group that can be substituted with an acidic group, and then an acidic group can be introduced. Alternatively, after synthesizing a tetraazaporphyrin derivative, a functional group can be introduced and substituted with an acidic group.

  For example, Compound Example 1 was synthesized as follows.

  V. N. Koplanenkov, L.M. S. Gonschlova, and E.G. A. Luk'yanets, J. et al. Gen. Chem. USSR. (Engl. Transl.), 47, 1954 (1977) to obtain a monobromo-tetra-t-butyltetraazaporphyrin metal-free product.

  Next, the monobromo-tetra-t-butyltetraazaporphyrin non-metal was heated and stirred in DMF together with zinc acetate to obtain a monobromo-tetra-t-butyltetraazaporphyrin zinc.

  The compound was heated and stirred in DMF together with acrylic acid, palladium acetate, potassium carbonate, and tetrabutylammonium bromide to obtain Compound Example 1.

  The sensitizing dye of the present invention thus obtained is sensitized by being contained in a semiconductor, and the effects described in the present invention can be achieved. Here, the inclusion of the sensitizing dye in the semiconductor means that the semiconductor is adsorbed on the surface of the semiconductor, and when the semiconductor has a porous structure such as a porous structure, the semiconductor has a porous structure filled with the sensitizing dye. An embodiment is mentioned.

The total content of the sensitizing dye of the present invention per 1 m ^{2 of} the semiconductor layer is preferably in the range of 0.01 mmol to 100 mmol, more preferably 0.1 mmol to 50 mmol, particularly preferably 0.5. Mmol to 20 mmol.

  When the sensitizing treatment is performed using the sensitizing dye of the present invention, the sensitizing dye may be used alone or in combination, and other compounds (for example, US Pat. No. 4,684). No. 5,537, No. 4,927,721, No. 5,084,365, No. 5,350,644, No. 5,463,057, No. 5,525. , 440, JP-A-7-249790, JP-A-2000-150007, etc.) can also be used as a mixture.

  In particular, when the photoelectric conversion element of the present invention is used as a solar cell, it is preferable to use two or more kinds of dyes having different absorption wavelengths so that the wavelength range of photoelectric conversion can be made as wide as possible to effectively use sunlight. In addition, it is necessary to use the sensitizing dye of the present invention for at least one photoelectric conversion element.

  In order to include the sensitizing dye of the present invention in the semiconductor layer, a method in which the sensitizing dye is dissolved in an appropriate solvent (such as ethanol) and the well-dried semiconductor layer is immersed in the solution for a long time is generally used. .

  When using a plurality of sensitizing dyes of the present invention in combination, or in combination with other sensitizing dyes, a sensitizing dye mixed solution may be prepared and used. It is also possible to prepare separate solutions for these sensitizing dyes and immerse them in each solution in turn. When preparing a separate solution for each sensitizing dye and immersing in each solution in order, the effect described in the present invention can be obtained regardless of the order in which the sensitizing dye is included in the semiconductor layer. be able to. Further, it may be produced by mixing semiconductor fine particles adsorbed with the sensitizing dye alone.

  The details of the sensitization treatment of the semiconductor layer according to the present invention will be specifically described in the photoelectric conversion element described later.

  In the case of a semiconductor layer with a high porosity, the adsorption treatment of sensitizing dye or the like may be completed before water is adsorbed on the semiconductor thin film and in the voids inside the semiconductor thin film due to moisture, water vapor, etc. preferable.

(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 metal (for example, platinum, gold, silver, copper, aluminum, rhodium, indium) or conductive metal oxide (for example, indium-tin composite oxide, tin oxide doped with fluorine) 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, and substantially transparent means that the light transmittance is 10% or more, more preferably 50% or more, and 80 % Or more is most 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 a transparent conductive support 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.

<< Production of photoelectrode >>
A method for producing a photoelectrode according to the present invention will be described.

  When the metal compound semiconductor of the photoelectrode according to the present invention is in the form of particles, the photoelectrode may be produced by applying or spraying the metal compound semiconductor onto a conductive support. In addition, when the metal compound semiconductor according to the present invention is in a film form and is not held on the conductive support, an oxide semiconductor is bonded onto the conductive support to produce a photoelectrode. Is preferred.

  As a preferred embodiment of the photoelectrode according to the present invention, a method of forming a semiconductor fine particle on the conductive support by firing is exemplified.

  When the semiconductor according to the present invention is produced by firing, the sensitizing treatment (adsorption, filling into the porous layer, etc.) of the semiconductor using a sensitizing dye is preferably performed 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.

  Hereinafter, a method for forming a photoelectrode by firing using semiconductor fine powder, which is preferably used in the present invention, will be described in detail.

(Preparation of coating liquid containing semiconductor fine powder)
First, a coating solution containing a fine powder of a metal compound semiconductor is prepared. The finer the primary particle diameter of the semiconductor fine powder, the better. The primary particle diameter is preferably 1 to 5000 nm, more preferably 2 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 metal compound 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 metal compound 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 coating solution containing fine semiconductor powder and baking treatment of the formed semiconductor layer)
The coating solution containing the metal compound semiconductor fine powder obtained as described above is applied or sprayed onto a conductive support, dried, etc., and then baked in air or in an inert gas to be conductive. A metal compound semiconductor layer (semiconductor film) is formed on the support.

  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.

  Thus, the semiconductor fine particle layer formed on the conductive layer such as the conductive support is weak in bonding strength with the conductive support and fine particles, and has low mechanical strength. The semiconductor fine particle layer is baked to increase the mechanical strength and form a semiconductor layer that is strongly fixed to the substrate.

  In the present invention, the semiconductor layer 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 layer 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 layer means a porosity that is penetrable in the thickness direction of the dielectric, and can be measured using a commercially available device such as a mercury porosimeter (Shimadzu Polarizer 9220 type).

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

  From the viewpoint of appropriately preparing 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 in the range of 200 to 800 ° C. Especially preferably, it is the range of 300-800 degreeC.

  The ratio of the actual surface area to the apparent surface area can be controlled by the particle size, specific surface area, firing temperature, etc. of the semiconductor fine particles. In addition, for the purpose of increasing the surface area of the semiconductor particles after heating, increasing the purity in the vicinity of the semiconductor particles, and increasing the efficiency of electron injection from the dye into the semiconductor particles, for example, chemical plating using a titanium tetrachloride aqueous solution or three An electrochemical plating process using a titanium chloride aqueous solution may be performed.

(Semiconductor sensitization treatment)
As described above, the sensitizing treatment of the metal compound semiconductor is performed by dissolving the sensitizing dye of the present invention in an appropriate solvent and immersing the substrate obtained by firing the semiconductor in the solution. In that case, it is preferable that 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. Such treatment allows the sensitizing dye of the present invention to enter deep inside the semiconductor layer (semiconductor film), and is particularly preferable when the semiconductor layer (semiconductor film) is a porous structure film.

  The solvent used for dissolving the sensitizing dye of the present invention is not particularly limited as long as it can dissolve the compound and does not dissolve the semiconductor or react with the semiconductor. However, in order to prevent moisture and gas dissolved in the solvent from entering the semiconductor film and hindering the sensitization treatment such as adsorption of the compound, it is preferable to deaerate and purify in advance.

  Solvents preferably used in dissolving the compound are alcohol solvents such as methanol, ethanol and n-propanol, ketone solvents such as acetone and methyl ethyl ketone, ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran and 1,4-dioxane. Solvents 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 metal compound semiconductor is baked in the solution containing the sensitizing dye of the present invention is sufficient for the compound to penetrate deeply into the semiconductor layer (semiconductor film) to sufficiently advance adsorption and the like to sufficiently increase the semiconductor. It is preferable to make it feel. In addition, from the viewpoint of suppressing degradation of the compound in the solution and preventing the decomposition product from interfering with the adsorption of the compound, it is preferably 3 to 48 hours, more preferably 4 to 24 hours, at 25 ° C. It is. 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.

  In soaking, the solution containing the sensitizing dye of the present invention may be heated to a temperature that does not boil as long as the dye does not decompose. A preferable 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.

"Electrolytes"
The electrolyte used in the present invention will be described.

In the photoelectric conversion element of the present invention, an electrolyte is filled between the counter electrodes to form an electrolyte layer. A redox electrolyte is preferably used as the electrolyte. Here, examples of the redox electrolyte include I ⁻ / I ³⁻ , Br ⁻ / Br ^{3 −} , and quinone / hydroquinone. Such a redox electrolyte can be obtained by a conventionally known method. For example, an I ⁻ / I ³⁻ type electrolyte can be obtained by mixing iodine ammonium salt and iodine. The electrolyte layer is composed of dispersions of these redox electrolytes. These dispersions are dispersed in liquid electrolytes when they are solutions, solid polymer electrolytes and gel substances when dispersed in polymers that are solid at room temperature. It is called a gel electrolyte. When a liquid electrolyte is used as the electrolyte 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 “Surface Science” Vol. 21, No. 5, pages 288 to 293.

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

The counter electrode only needs to have conductivity, and any conductive material can be used, but it has a catalytic ability to oxidize I ³⁻ ions and other redox ions at a sufficiently high rate. Is preferably used. 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.

[Solar cell]
The solar cell of the present invention will be described.

  The solar cell of the present invention has a structure in which optimum design and circuit design for sunlight are performed as one aspect of the photoelectric conversion element of the present invention, and optimal photoelectric conversion is performed when sunlight is used as a light source. Have That is, it has a structure in which sunlight can be applied to a dye-sensitized metal compound semiconductor. When constituting the solar cell of the present invention, it is preferable that the photoelectrode, the electrolyte 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 sensitizing dye according to the present invention adsorbed on the metal compound semiconductor absorbs the irradiated light or electromagnetic wave and excites it. Electrons generated by excitation move to the metal compound semiconductor, and then move to the counter electrode via the conductive support, thereby reducing the redox electrolyte of the charge transfer layer. On the other hand, the sensitizing dye according to 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 via the redox electrolyte of the electrolyte layer, and the original sensitizing dye is reduced. At the same time, the redox electrolyte of the charge transfer layer is oxidized and returned to a state where it can be reduced again by the electrons supplied from the counter electrode. In this way, electrons flow, and a solar cell using the photoelectric conversion element of the present invention can be configured.

Examples 1-12
A commercially available titanium oxide paste (particle size 18 nm) was applied to a fluorine-doped tin oxide (FTO) conductive glass substrate by a doctor blade method so that the film thickness after sintering was about 5 μm, and heated at 60 ° C. for 10 minutes. The paste was dried and baked at 500 ° C. for 30 minutes. Next, the dye was dissolved in ethanol to prepare a 3 × 10 ⁻⁴ M solution. The FTO glass substrate coated with titanium oxide was immersed in this solution at room temperature for 16 hours to perform dye adsorption treatment, then washed with acetonitrile and dried to obtain a photoelectric conversion electrode. As the electrolytic solution, a 3-methylpropionitrile solution containing 0.4 M lithium iodide, 0.05 M iodine, and 0.5 M 4- (t-butyl) pyridine was used. A platinum plate was used as a counter electrode, and a photoelectric conversion cell was obtained by assembling the photoelectric conversion electrode prepared earlier, an electrolyte, and a clamp cell.

Comparative Examples 1 and 2
In Example 1, a cell was produced in the same manner as in Example 1 except that Compound A or Compound B was used instead of the exemplified dye.

Example 13
A photoelectric conversion cell was produced in the same manner as in Example 1 except that the semiconductor layer was SnO _{2 in} Example 1.

Comparative Example 3
A photoelectric conversion cell was produced in the same manner as in Example 1 except that the dye was changed to Compound B in Example 13.

Evaluation The photoelectric conversion electrodes thus obtained were exposed in a 13 ppm ozone atmosphere for 20 minutes, and the changes in the power generation characteristics of the photoelectric conversion cells assembled in the same manner were compared. The compounds shown in Table 1 were used as sensitizing dyes.

In the evaluation, photoelectric conversion characteristics were measured under conditions where a 5 × 5 mm ² mask was put on the oxide semiconductor electrode under irradiation of a xenon lamp having an intensity of 100 mW / cm ² . That is, for the photoelectric conversion element of the example, current-voltage characteristics were measured at room temperature using an IV tester, and a short circuit current (Jsc), an open circuit voltage (Voc), and a form factor (FF) were measured. The photoelectric conversion efficiency (η (%)) was determined from these. In addition, the photoelectric conversion efficiency ((eta) (%)) of the solar cell was computed based on the following formula (A).

η = 100 × (Voc × Jsc × FF) / P (A)
Here, P is the incident light intensity [mW / cm ⁻² ], Voc is the open circuit voltage [V], Jsc is the short circuit current density [mA · cm ⁻² ], F. Indicates a form factor.

  Table 1 shows the characteristics evaluation with and without ozone exposure.

  It turns out that the pigment | dye of an Example is excellent in stability with respect to ozone compared with a comparative example, and shows favorable conversion efficiency.

It is a structure sectional view showing an example of a photoelectric conversion element used for the present invention.

Explanation of symbols

1, 1 'substrate 2, 7 transparent conductive film 3 metal compound semiconductor 4 sensitizing dye 5 electrolyte 6 counter electrode 8 platinum (Pt)

Claims (8)

A photoelectric conversion element comprising a compound having a structure represented by the following general formula (1) between opposing electrodes.

[Wherein R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom, a nitro group, a cyano group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a thioalkyl group, an amino group, which may be substituted. Represents an aryl group, a hydroxyl group, a carbonyl group, a thiol group, or a heterocyclic group. R _{1 to} R ₈ may form a cyclic structure or a condensed ring structure directly or via another bonding atom.
At least two or more of R _{1 to} R ₈ have a substituent other than hydrogen.
M represents two hydrogen atoms, or represents a divalent, trivalent, or tetravalent metal atom that may have an oxygen, halogen atom, or other ligand. ] The photoelectric conversion element according to claim 1, wherein the compound having the structure of the general formula (1) contains an acidic group. In Formula (1), the photoelectric conversion element according to claim 1 or 2 R ₁ to R ₈ is characterized in that it is a compound having at least one substituent having a bulky structure. The general formula (1), wherein M is any one of Cu, Ni, Zn, Pd, VO, Co, Mg, and H ₂ . Photoelectric conversion element. In the dye-sensitized photoelectric conversion element in which at least a semiconductor layer and an electrolyte layer are provided between the counter electrodes, a semiconductor layer and an electrolyte layer in which the compound having the structure of the general formula (1) is supported are provided. The photoelectric conversion element according to any one of claims 1 to 4, wherein the photoelectric conversion element is formed. The photoelectric conversion element according to claim 1, wherein the semiconductor forming the semiconductor layer is titanium oxide. The photoelectric conversion element according to claim 1, wherein the semiconductor forming the semiconductor layer is tin oxide. It has a photoelectric conversion element of any one of Claims 1-7, The solar cell characterized by the above-mentioned.

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