JP2013012388A - Photoelectric conversion element, method for manufacturing the same, photoelectric conversion module, laminate, and photoelectrode material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric conversion element capable of having a substrate composed of a polymeric resin substrate, such as a polymeric film, and achieving low manufacturing costs, a method for manufacturing the same, a photoelectric conversion module, a laminate, and a photoelectrode material.SOLUTION: The photoelectric conversion element comprises a laminate of a photoelectrode layer, an insulating layer, and a catalyst layer, a conductive substrate, and a transparent conductive layer. The laminate intervenes between the conductive substrate and the transparent conductive layer, and the photoelectrode layer and at least one of the insulating layer and the catalyst layer are burned products made from green sheets.

Description

  The present technology relates to a photoelectric conversion element and a manufacturing method thereof, a photoelectric conversion module, a laminate, and a photoelectrode material. In detail, it is related with the photoelectric conversion element which can use a polymeric resin base material as a base material, and its manufacturing method.

  From the viewpoint of effective use of resources and prevention of environmental pollution, solar cells that directly convert sunlight into electrical energy have attracted attention and research and development have been promoted. In particular, in recent years, research and development of dye-sensitized solar cells have been actively conducted as solar cells that require enormous energy for production and replace expensive silicon-based solar cells.

  For example, the following Non-Patent Document 1 and Patent Document 1 include a photoelectric conversion electrode and a dye-sensitized solar cell using a porous semiconductor layer sensitized with a dye, and a material and a manufacturing technique for producing the electrode. Is disclosed. Further, for example, Patent Document 2 below discloses a dye-sensitized photoelectric conversion element module in which a plurality of dye-sensitized photoelectric conversion elements are connected in series and a method for manufacturing the same.

  A conventionally proposed dye-sensitized photoelectric conversion cell (photoelectric conversion element) includes a titanium oxide porous layer (working electrode) spectrally sensitized with a sensitizing dye such as a ruthenium complex, an electrolyte mainly composed of iodine, And a counter electrode. The first advantage of this battery is that an inexpensive photoelectric conversion element can be provided because an inexpensive oxide semiconductor such as titanium oxide is used. The second advantage is that a relatively high conversion efficiency can be obtained because the ruthenium complex used has a wide absorption in the visible light region.

  When forming a titanium oxide porous layer, it is common to prepare a dispersion paste of titanium oxide particles, apply it on a substrate, and apply a temperature of 400 ° C. or higher to the applied paste. . By applying a temperature of 400 ° C. or higher to the applied paste, additives such as a binder in the paste are removed, and the titanium oxide particle layer becomes porous. Further, necking occurs between the titanium oxide particles, the electron transfer property in the titanium oxide particle layer is improved, and the photoelectric conversion efficiency of the dye-sensitized photoelectric conversion cell is improved.

  As described above, the production of a dye-sensitized photoelectric conversion cell usually requires a high-temperature sintering process. For this reason, the material of the base material is limited to a material having high heat resistance such as glass, and the material cost of the base material and the energy cost to be consumed at the time of manufacture are increased, and the manufacturing cost of the dye-sensitized photoelectric conversion cell Becomes higher.

  Therefore, in order to use a resin base material, a firing method in which a temperature at which the resin does not dissolve is given and the titanium oxide porous layer is fired at a low temperature has been attempted (see Non-Patent Document 2). In addition, a method of transferring an oxide semiconductor film obtained by forming a layer containing an oxide semiconductor or a precursor thereof on a heat-resistant substrate and heating and firing the layer onto a substrate to be transferred has been tried ( (See Patent Document 3).

  However, in consideration of the heat resistance of the resin substrate, it is difficult to add an additive such as a binder when the firing temperature of the dispersion paste is set to about 150 ° C. or less, and it is difficult to adjust the viscosity of the dispersion paste. . It is also difficult to pattern the mixing ratio of the dispersion paste materials. Therefore, process man-hours and manufacturing costs increase. Moreover, in low temperature baking, the connectivity by necking also decreases, and the conversion efficiency of the dye-sensitized photoelectric conversion cell remains low. Furthermore, in the method of transferring the oxide semiconductor film obtained by heating and baking onto the substrate to be transferred, the titanium oxide porous layer after baking becomes very brittle due to the removal of the binder and the like. Have difficulty.

B. O'Regan, M. Graetzel, Nature, 353, p. 737-740 (1991) ECN contributions 16th European Photovoltaic Solar Energy Conference and Exhibition, May 1-5, 2000 abstract; P.M.Sommeling et.al, “Flexible dye-sensitizednanocristalline TiO2 solar cells”

US Pat. No. 4,927,721 JP 2009-110797 A JP 2002-184475 A

  Therefore, the objective of this technique aims at providing the photoelectric conversion element which can use a polymer resin base material as a base material, its manufacturing method, a photoelectric conversion module, a laminated body, and a photoelectrode material.

In order to solve the above-described problem, the first technique is:
A laminate of a photoelectrode layer, an insulating layer and a catalyst layer;
A conductive substrate;
A transparent conductive layer, and
The laminate is interposed between the conductive substrate and the transparent conductive layer,
The photoelectrode layer and at least one of the insulating layer and the catalyst layer is a photoelectric conversion element that is a fired body of a green sheet.

The second technology is
A photoelectrode layer;
An insulating layer;
A catalyst layer;
A collecting electrode, and
The collecting electrode is interposed between the photoelectrode layer and the insulating layer,
The catalyst layer is provided on one main surface of the insulating layer,
The photoelectrode layer and at least one of the insulating layer and the catalyst layer is a photoelectric conversion element that is a fired body of a green sheet.

The third technology is
Forming a laminate comprising a photoelectrode layer precursor, an insulating layer precursor and a catalyst layer precursor;
A step of firing the laminate,
The photoelectrode layer precursor and at least one of the insulating layer precursor and the catalyst layer precursor is a method for producing a photoelectric conversion element comprising a green sheet.

The fourth technology is
Forming a photoelectrode layer precursor on one main surface of the collecting electrode;
Forming an insulating layer precursor and a catalyst layer precursor on one main surface of the conductive substrate;
A collector electrode on which the other main surface of the collector electrode and the insulating layer precursor are bonded to face each other to form a photoelectrode layer precursor, and a conductive substrate on which the insulating layer precursor and the catalyst layer precursor are formed Forming a laminated body integrated with each other;
A step of firing the laminate,
The photoelectrode layer precursor and at least one of the insulating layer precursor and the catalyst layer precursor is a method for producing a photoelectric conversion element comprising a green sheet.

The fifth technology is
A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
It is a laminate in which a catalyst layer precursor, an insulating layer precursor, and a photoelectrode layer precursor are sequentially laminated.

The sixth technology is
A conductive substrate;
A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
A photoelectrode material in which a catalyst layer precursor, an insulating layer precursor, and a photoelectrode layer precursor are sequentially laminated on one main surface of a conductive substrate.

  By making the photoelectrode layer and at least one of the insulating layer and the catalyst layer into a fired body of the green sheet, the green sheet itself has flexibility, so the workability in the manufacturing process of the photoelectric conversion element is improved. . The green sheet can be easily cut into a desired shape, and the photoelectric conversion element can be easily enlarged. In addition, after firing at a temperature of 400 ° C. or higher, the photoelectrode layer, the insulating layer, and the catalyst layer can be disposed on the polymer resin substrate, thereby suppressing a decrease in conversion efficiency of the photoelectric conversion element. be able to. It is preferable that the green sheet, which is an unfired body of the photoelectrode layer, contains semiconductor fine particles, and thus the photoelectrode layer contains semiconductor fine particles. This is because by firing the green sheet, a porous semiconductor layer in which necking occurs between the semiconductor fine particles can be obtained.

  The photoelectrode layer, the insulating layer, and the catalyst layer are preferably green sheet fired bodies. This is because workability in the manufacturing process of the photoelectric conversion element is further improved. This is because by using a green sheet as a precursor for the photoelectrode layer, the insulating layer, and the catalyst layer, it is possible to simplify the manufacturing process, reduce the equipment investment by simultaneous processing, and shorten the lead time. In addition, the photoelectrode layer, the insulating layer, or the catalyst layer can be formed thick. In addition, these green sheets can also be easily made into a laminated structure only by superposing a plurality of different types of sheets and applying pressure.

  The conductive base material is preferably flexible, and the laminate composed of the photoelectrode layer precursor, the insulating layer precursor, and the catalyst layer precursor is arranged such that the catalyst layer is disposed on the conductive base material side. It is preferable to be bonded to the conductive substrate. This is because the conductive substrate can be used as a support substrate for the green sheet, and the workability in the manufacturing process of the photoelectric conversion element is further improved. Furthermore, even after the green sheet is fired, the photoelectrode layer, the insulating layer, and the catalyst layer can be easily handled. The fired green sheet can be obtained by, for example, simply pressing the green sheet to a substrate having a transparent conductive layer formed on one main surface without using a special binder or adhesive. A sheet | seat and a transparent conductive layer can be bonded together.

  It is preferable that the photoelectric conversion element further includes a flexible resin base material, and the transparent conductive layer is formed on the resin base material. Or it is preferable that the laminated body of a photoelectrode layer, an insulating layer, and a catalyst layer has a curved-surface shape. This is because the green sheet as the precursor of the photoelectrode layer, the insulating layer, and the catalyst layer has flexibility, so that the photoelectric conversion element can have a shape other than a flat plate shape, for example, a curved shape. By using a polymer resin base material as a base material, the photoelectric conversion element can be configured to be lightweight. Therefore, even when a photoelectric conversion module is configured by electrically connecting a plurality of photoelectric conversion elements, The photoelectric conversion module can be configured to be lightweight. Furthermore, according to the present technology, since the shape of the photoelectric conversion element can be, for example, a curved shape, when the photoelectric conversion module is configured, the degree of freedom such as the shape and installation location of the photoelectric conversion module is improved.

  According to the present technology, a polymer resin substrate such as a polymer film can be used as a substrate, and a photoelectric conversion element, a manufacturing method thereof, a photoelectric conversion module, a laminate, and a photoelectrode material with reduced manufacturing costs are provided. be able to.

FIG. 1 is a schematic cross-sectional view illustrating an example of the configuration of the photoelectric conversion element according to the first embodiment of the present technology. 2A to 2D are diagrams for describing an example of a method for manufacturing a photoelectric conversion element according to the first embodiment of the present technology. Drawing 3A-Drawing 3D are figures for explaining an example of a manufacturing method of a photoelectric conversion element concerning a 1st embodiment of this art. FIG. 3E is a perspective view illustrating a configuration example of a laminate in which a photoelectrode layer precursor, an insulating layer precursor, and a catalyst layer precursor are sequentially laminated. FIG. 3F is a diagram for describing an example of the manufacturing method of the photoelectric conversion element according to the first embodiment of the present technology. 4A to 4D are diagrams for describing an example of a method for manufacturing a photoelectric conversion element according to the first embodiment of the present technology. FIG. 5A and FIG. 5B are diagrams for explaining an example of the method for manufacturing the photoelectric conversion element according to the first embodiment of the present technology. 6A to 6F are diagrams for explaining another example of the method for manufacturing the photoelectric conversion element according to the first embodiment of the present technology. Drawing 7A-Drawing 7D are figures for explaining other examples of a manufacturing method of a photoelectric conversion element concerning a 1st embodiment of this art. FIG. 8A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion element according to the second embodiment of the present technology. 8B to 8D are diagrams for describing an example of a method for manufacturing a photoelectric conversion element according to the second embodiment of the present technology. 9A to 9C are diagrams for describing an example of a method for manufacturing a photoelectric conversion element according to the second embodiment of the present technology. FIG. 10A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion element according to a third embodiment of the present technology. 10B to 10D are diagrams for explaining an example of a method for manufacturing a photoelectric conversion element according to the third embodiment of the present technology. FIG. 11A to FIG. 11D are diagrams for explaining an example of a method for manufacturing a photoelectric conversion element according to the third embodiment of the present technology. FIG. 12A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion module according to the fourth embodiment of the present technology. FIG. 12B is a schematic cross-sectional view illustrating a first modification of the configuration of the photoelectric conversion module according to the fourth embodiment of the present technology. FIG. 12C is a schematic cross-sectional view illustrating a second modification example of the configuration of the photoelectric conversion module according to the fourth embodiment of the present technology. FIG. 13A is a schematic cross-sectional view illustrating an example of a photoelectric conversion module in which a plurality of stacked layers of a photoelectrode layer, an insulating layer, a catalyst layer, and a conductive base material are sealed. FIG. 13B is a schematic cross-sectional view illustrating an example of a photoelectric conversion module in which a plurality of stacked bodies of a photoelectrode layer, a collecting electrode, an insulating layer, a catalyst layer, and a conductive base material are sealed. 14A is a graph showing the measurement results of photoelectric conversion efficiency for the photoelectric conversion elements of Sample 1 and Sample 2. FIG. FIG. 14B is a graph showing measurement results of electrical characteristics of the photoelectric conversion elements of Sample 1 and Sample 2.

Embodiments of the present technology will be described in the following order with reference to the drawings. In all the drawings of the following embodiments, the same or corresponding parts are denoted by the same reference numerals.
1. First embodiment (example of laminated structure)
2. Second embodiment (example of monolithic structure)
3. Third Embodiment (Example of TCO-free structure)
4). Fourth Embodiment (Example of photoelectric conversion module)

<1. First Embodiment>
[Configuration of photoelectric conversion element]
FIG. 1 is a schematic cross-sectional view illustrating an example of the configuration of the photoelectric conversion element according to the first embodiment of the present technology. As shown in FIG. 1, the photoelectric conversion element 1 includes a laminate 13 of a photoelectrode layer 3, an insulating layer 5 and a catalyst layer 7, a conductive base material 9, and a transparent conductive layer 15. The conductive substrate 9 and the transparent conductive layer 15 are disposed to face each other, and the laminate 13 and the electrolytic solution 21 are interposed between the conductive substrate 9 and the transparent conductive layer 15. The laminate 13 is interposed between the conductive substrate 9 and the transparent conductive layer 15 so that the catalyst layer 7 is disposed on the conductive substrate 9 side. The laminate 13 and the electrolytic solution 21 are sealed with the conductive base material 9, the transparent conductive layer 15, and the sealing material 19. Specifically, the photoelectrode layer 3 is a porous semiconductor layer on which a dye is supported. Therefore, the photoelectric conversion element 1 constitutes a so-called dye-sensitized solar cell. In the configuration example shown in FIG. 1, the base material 17 and the transparent conductive layer 15 are transparent. For example, the base material 17 has another main surface opposite to the one main surface on which the transparent conductive layer 15 is formed. The other main surface is a light receiving surface that receives irradiation of light such as sunlight.

  In the present technology, the photoelectrode layer 3 is a fired green sheet. Furthermore, at least one of the insulating layer 5 and the catalyst layer 7 is a green sheet fired body.

  Hereinafter, the photoelectrode layer 3, the insulating layer 5, the catalyst layer 7, the conductive base material 9 and the transparent conductive layer 15, the base material 17, the sealing material 19, and the electrolytic solution 21 that constitute the photoelectric conversion element 1 will be described in order. .

(Photoelectrode layer)
The photoelectrode layer 3 is a layer containing semiconductor fine particles, and includes, for example, semiconductor fine particles carrying a sensitizing dye. The photoelectrode layer 3 is preferably a porous semiconductor layer containing metal oxide semiconductor fine particles. The metal oxide semiconductor fine particles preferably contain a metal oxide containing at least one of titanium, zinc, tin and niobium. Specifically, the material of the metal oxide semiconductor fine particles includes titanium oxide, tin oxide, tungsten oxide, zinc oxide, indium oxide, niobium oxide, iron oxide, nickel oxide, cobalt oxide, strontium oxide, tantalum oxide, and antimony oxide. One or more selected from the group consisting of lanthanoid oxide, yttrium oxide, vanadium oxide, and the like can be used, but is not limited thereto. In order for the surface of the porous semiconductor layer to be sensitized by the sensitizing dye, the conduction band of the porous semiconductor layer is preferably present at a position where electrons are easily received from the photoexcitation level of the sensitizing dye. From this viewpoint, among the materials of the metal oxide semiconductor fine particles described above, one or more selected from the group consisting of titanium oxide, zinc oxide, tin oxide, and niobium oxide is particularly preferable. Furthermore, titanium oxide is most preferable from the viewpoints of price and environmental hygiene. The metal oxide semiconductor fine particles particularly preferably contain titanium oxide having an anatase type or brucite type crystal structure. By including such titanium oxide, an appropriate energy band is formed between the dye to be adsorbed and the metal oxide, and then electrons generated in the dye by light irradiation are smoothly transmitted to the metal oxide, and thereafter This is because it can contribute to power generation by oxidation-reduction of iodine.

  The average primary particle diameter of the metal oxide semiconductor fine particles is preferably 5 nm or more and 500 nm or less, more preferably 10 nm or more and 100 nm or less, and particularly preferably 10 nm or more and 60 nm or less. By making the average primary particle diameter within the range of 10 nm or more and 100 nm or less, the denseness of the porous semiconductor layer is not deteriorated, and the adsorption of the dye is inhibited or the penetration of the electrolytic solution is inhibited by being too dense. It is because it can prevent. When the average primary particle size is less than 5 nm, the crystallinity is extremely deteriorated, and the anatase structure cannot be maintained and an amorphous structure tends to be obtained. On the other hand, when the average primary particle diameter exceeds 500 nm, the specific surface area is remarkably lowered, and the total amount of the dye contributing to power generation to be adsorbed on the porous semiconductor layer tends to decrease. Here, the average primary particle diameter was determined by a method of measuring by a light scattering method using a dilute solution in which a desired dispersant was added and dispersed to primary particles using a solvent system in which primary particles can be dispersed. Is.

  Metal oxide semiconductor fine particles having different particle size distributions may be mixed. In the present technology, as described later, the photoelectrode layer 3 is a green sheet fired body. In the preparation of a slurry for forming a green sheet (a composition for forming a green sheet), metal oxide semiconductor fine particles, a binder, a plasticizer, a solvent, and the like are mixed. The particle size of can be appropriately selected depending on the desired plasticity of the green sheet.

  In the present technology, as described later, the photoelectrode layer 3 is obtained by supporting a sensitizing dye on the porous semiconductor layer obtained by firing the green sheet.

  The sensitizing dye for photoelectric conversion is not particularly limited as long as it exhibits a sensitizing action, but usually a substance capable of absorbing light in the vicinity of the visible light region, for example, a bipyridine complex, a terpyridine complex, a merocyanine dye, a porphyrin , And phthalocyanine are used.

  As a sensitizing dye used alone, for example, cis-bis (isothiocyanato) bis (2,2′-bipyridyl-4,4′-dicarboxylic acid) ruthenium (II) ditetrabutylammonium complex which is one kind of bipyridine complex (Commonly known as N719) is excellent in performance as a sensitizing dye and is generally used. In addition, cis-bis (isothiocyanato) bis (2,2′-bipyridyl-4,4′-dicarboxylic acid) ruthenium (II) (common name: N3), which is a kind of bipyridine complex, is a kind of terpyridine complex. Tris (isothiocyanato) (2,2 ′: 6 ′, 2 ″ -terpyridyl-4,4 ′, 4 ″ -tricarboxylic acid) ruthenium (II) tritetrabutylammonium complex (commonly known as black dye) is generally used.

  In particular, when N3 or a black die is used, a co-adsorbent is often used. The co-adsorbent is a molecule added to prevent the dye molecules from associating on the porous semiconductor layer. Typical co-adsorbents include, for example, chenodeoxycholic acid, taurodeoxycholate, and 1 -Decylphosphonic acid and the like. The structural features of these molecules are that they have a carboxyl group, a phosphono group, etc. as functional groups that are easily adsorbed to titanium oxide constituting the porous semiconductor layer, and are interposed between dye molecules. In order to prevent interference, it may be formed by σ coupling.

  Examples of other sensitizing dyes include azo dyes, quinacridone dyes, diketopyrrolopyrrole dyes, squarylium dyes, cyanine dyes, merocyanine dyes, triphenylmethane dyes, xanthene dyes, porphine dyes. Chlorophyll dyes, ruthenium complex dyes, indigo dyes, perylene dyes, oxazine dyes, anthraquinone dyes, phthalocyanine dyes, naphthalocyanine dyes, and their derivatives, but they absorb light and are porous semiconductors. Any sensitizing dye capable of injecting excited electrons into the conduction band of the layer is not limited thereto. When these sensitizing dyes have one or more linking groups in their structure, they can be connected to the surface of the porous semiconductor layer, and the excited electrons of the photoexcited sensitizing dye are transferred to the conduction band of the porous semiconductor layer. This is desirable because it can be communicated quickly.

  The thickness of the photoelectrode layer 3 is preferably 1 μm or more and 50 μm or less. By setting the thickness of the photoelectrode layer 3 within the above range, cracking and peeling are less likely to occur when the photoelectrode layer 3 is formed, and the formation of the photoelectrode layer 3 can be stabilized. In addition, the distance between the surface layer of the photoelectrode layer 3 and the transparent conductive layer 15 can be within an appropriate range, and the generated charges are effectively transmitted to the conductive surface, so that good conversion efficiency can be obtained.

(Insulating layer)
The insulating layer 5 is a layer provided to prevent an electrical short circuit due to the direct contact between the photoelectrode layer 3 and the catalyst layer 7. The insulating layer 5 is preferably a porous layer. This is because the oxidant in the electrolytic solution 21 between the photoelectrode layer 3 and the catalyst layer 7 can smoothly move when the electrolytic solution 21 penetrates into the insulating layer 5. For example, when using a redox species of I ⁻ / I ₃ ⁻ as a redox pair, an oxidant generated in the photoelectrode layer 3, for example, I ₃ ⁻ (a combination of I ₂ and I ⁻ ) is insulated. It moves through the electrolyte solution 21 that has penetrated into the layer 5 to reach the catalyst layer 7, receives electrons from the catalyst layer 7, and is reduced. As will be described later, since the impregnation of the electrolytic solution 21 into the insulating layer 5 can be performed at the final stage of the manufacturing process of the photoelectric conversion element, workability in the manufacturing process of the photoelectric conversion element does not deteriorate. .

  The material of the insulating layer 5 is made of, for example, at least one material (for example, a metal oxide material) selected from the group consisting of titanium oxide, zirconium oxide, silicon oxide (silica), aluminum oxide, and the like. It can be in the form. In the present technology, at least one of the insulating layer 5 and the catalyst layer 7 is a fired body of a green sheet. When the insulating layer 5 is not a fired green sheet, the insulating layer 5 may be formed by various wet methods or various dry methods. Examples of the wet method include a coating method and a printing method using a solution containing a material constituting the insulating layer 5. Examples of the dry method include physical vapor deposition (PVD) methods such as sputtering and vacuum vapor deposition, and various chemical vapor deposition (CVD) methods. . The insulating layer may be composed of a woven fabric, a nonwoven fabric, or a laminated structure of a woven fabric or a nonwoven fabric and a layer made of the above-described material. Examples of the material constituting the woven fabric or the nonwoven fabric include synthetic fibers. Specific examples of synthetic fibers include polyethylene, polypropylene, polyester, polytetrafluoroethylene, polyimide, polyphenylene sulfide, polyvinyl alcohol, aramid, nylon (registered trademark), vinylon, polyolefin, rayon, low density polyethylene, and ethylene. Examples include vinyl acetate, copolyamide, copolyester, and the like, natural fibers of cotton, cellulose, glass fiber, and synthetic rubber in the form of fibers.

(Catalyst layer)
The catalyst layer 7 is a layer provided in order to promote the reduction reaction of I ₃ ⁻ or the like in the electrolytic solution 21 and perform the reduction reaction at a sufficient rate. The material of the catalyst layer 7 may be any material that has a catalytic ability to cause the reduction reaction at a sufficient rate. For example, carbon (C), platinum (Pt), rhodium (Rh), ruthenium (Ru), iridium (Ir) and the like can be mentioned. In the present technology, at least one of the insulating layer 5 and the catalyst layer 7 is a fired body of a green sheet. When the catalyst layer 7 is not a green sheet fired body, the catalyst layer 7 may be formed by various wet methods or various dry methods. Examples of the wet method include a coating method and a printing method using a solution containing a material constituting the catalyst layer 7. Examples of the dry method include physical vapor deposition methods such as sputtering and vacuum vapor deposition, and various chemical vapor deposition methods.

(Conductive substrate)
The conductive base material 9 is disposed to face the transparent conductive layer 15, and the conductive base material 9 has one main surface that faces the transparent conductive layer 15, and the catalyst layer 7 is formed on the one main surface. The counter electrode of the dye-sensitized solar cell (photoelectric conversion element 1) is configured by the conductive base material 9 and the catalyst layer 7 formed on one main surface of the conductive base material 9. The counter electrode functions as a positive electrode of the dye-sensitized solar cell.

  The material of the conductive base material 9 may be conductive as long as it is conductive, and examples thereof include, but are not limited to, a metal substrate or foil. Examples of the metal include platinum, gold, silver, copper, titanium, aluminum, rhodium, and indium, but are not limited thereto. In addition, if a conductive layer is formed on one main surface of the insulating base and the main surface on the side where the conductive layer is formed is opposed to the photoelectrode layer 3, the insulating base and the conductive base are electrically conductive. It is also possible to use a pair with a conductive layer as the conductive substrate 9.

  The conductive substrate 9 preferably has flexibility. This is because by disposing a green sheet on the conductive substrate 9, the conductive substrate 9 can be used as a support substrate for the green sheet. Therefore, handling of the green sheet and handling of the green sheet fired body are facilitated, and workability in the manufacturing process of the photoelectric conversion element 1 is improved. Although there is no restriction | limiting in particular in the thickness of the electrically conductive base material 9, It is preferable that it is 30 micrometers or more from a viewpoint which makes the electrically conductive base material 9 the support base material of a green sheet.

(Transparent conductive layer)
The transparent conductive layer 15 is provided, for example, on one main surface of the substrate 17 described later. Electrons in the sensitizing dye that have been excited by absorbing photons reach the transparent conductive layer 15 through the photoelectrode layer 3 and are extracted from the transparent conductive layer 15 to an external circuit.

The transparent conductive layer 15 preferably has little light absorption from the visible to the near infrared region of sunlight. As a material for the transparent conductive layer 15, for example, a metal oxide or carbon having good conductivity is preferably used. Examples of the metal oxide include indium-tin composite oxide (ITO), fluorine-doped SnO ₂ (FTO), antimony-doped SnO ₂ (ATO), tin oxide (SnO ₂ ), zinc oxide (ZnO), and indium-zinc. One or more selected from the group consisting of composite oxide (IZO), aluminum-zinc composite oxide (AZO), and gallium-zinc composite oxide (GZO) can be used. A layer may be further provided between the transparent conductive layer 15 and the photoelectrode layer 3 for the purpose of promoting binding, improving electron transfer, or preventing a reverse electron process. Further, for example, in order to remove organic substances on the surface of the transparent conductive layer 15, an ultraviolet irradiation process or an ozone (O ₃ ) process may be performed as a cleaning process.

(Base material)
The substrate 17 is not particularly limited as long as it is a substrate having transparency. As the substrate having transparency, for example, a transparent inorganic substrate or a transparent organic substrate can be used, and a substrate that absorbs less light from the visible to the near infrared region of sunlight is preferable. Examples of the transparent inorganic substrate include a glass substrate, a sapphire substrate, and a quartz substrate, and examples of the glass substrate include blue plate, BK7, and lead glass, but are not limited thereto. It is not a thing. Examples of the transparent organic substrate include a resin substrate. Examples of the resin substrate include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polyester, polyethylene (PE), polycarbonate ( PC), polyvinyl butyrate, polypropylene (PP), polyvinylidene fluoride, tetraacetyl cellulose, syndioctaic polystyrene, polyphenylene sulfide, polyarylate, polysulfone, polyester sulfone, polyether imide, cyclic polyolefin, brominated phenoxy, vinyl chloride However, it is not limited to these. For example, a film, a sheet, a substrate, or the like can be used as the base material 17, but is not limited thereto.

  It is preferable that the base material 17 is a resin base material having flexibility. Moreover, it is preferable that the transparent conductive layer 15 is formed on the base material 17 which consists of a resin base material which has flexibility. In the present technology, the photoelectrode layer 3 and at least one of the insulating layer 5 and the catalyst layer 7 are used as a green sheet fired body. Therefore, the shape of the base material 17 is not limited to a flat plate shape. For example, by baking in a state where the green sheet is bent, the photoelectric conversion element 1 can be configured using, for example, the base material 17 having a curved shape and the transparent conductive layer 15 formed thereon. By using a flexible resin base material as the base material 17, the photoelectric conversion element can be made into a shape other than a flat plate shape, and the photoelectric conversion element can be reduced in weight. The degree of freedom of form is improved. For example, the photoelectric conversion element can be easily installed on a three-dimensional structure such as a roof, a wall surface, or a window of a building. In the case where the photoelectric conversion element has a shape other than a flat plate shape such as a curved surface shape, the laminate 13 composed of the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7 preferably has a curved surface shape.

(Encapsulant)
A sealing material 19 is provided between the conductive substrate 9 and the transparent conductive layer 15 so as to surround the stacked body 13 of the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7. The sealing material 19 is provided to prevent leakage and volatilization of the electrolyte solution 21 described later. The distance between the photoelectrode layer 3 and the catalyst layer 7 (which may be referred to as the thickness of the insulating layer 5) is preferably 1 to 100 μm, more preferably 1 to 20 μm. The material of the sealing material 19 is preferably resistant to the electrolytic solution 21, and for example, a resin, ceramic, glass frit, or the like that is resistant to the electrolytic solution 21 can be used. As a material of the sealing material 19, for example, a heat-sealing film, a thermosetting resin, an ultraviolet curable resin, or the like can be used. Specifically, for example, an epoxy resin, a polyisobutylene resin, a urethane resin, Various heat-sealing films such as silicon resin, polyolefin resin, acrylic adhesive, ethylene vinyl acetate (EVA), ionomer resin, biaxially stretched polypropylene film and polyethylene film can be used.

(Electrolyte)
The electrolytic solution 21 is sealed in a space surrounded by the conductive base material 9, the transparent conductive layer 15, and the sealing material 19. Although not shown in FIG. 1, for example, the conductive base material 9 is provided with an injection port that is used for injection of an electrolytic solution and is finally closed.

The electrolytic solution 21 is preferably composed of an electrolyte, a medium, and an additive. The electrolyte is a mixture of iodine (I ₂ ) and iodide (for example, LiI, NaI, KI, CsI, MgI ₂ , CaI ₂ , CuI, tetraalkylammonium iodide, pyridinium iodide, imidazolium iodide, etc.), Br A mixture of ₂ and bromide (for example, LiBr) is preferable, and among these, an electrolyte in which LiI, pyridinium iodide, imidazolium iodide, or the like is mixed as a combination of I ₂ and iodide is preferable, but not limited to this combination.

As for the concentration of the electrolyte with respect to the medium, I ₂ is preferably 0.01 M or more and 0.5 M or less, and the iodide mixture is preferably 0.1 M or more and 15 M or less. Further, various additives such as 4-tert-butylpyridine and benzimidazoliums can be added for the purpose of improving the open-circuit voltage of the dye-sensitized solar cell.

  The medium used for the electrolytic solution 21 is preferably a compound that can exhibit good ionic conductivity. Examples of the solution medium include ether compounds such as dioxane and diethyl ether, chain ethers such as ethylene glycol dialkyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, and polypropylene glycol dialkyl ether, methanol, ethanol, and ethylene glycol. Alcohols such as monoalkyl ether, propylene glycol monoalkyl ether, polyethylene glycol monoalkyl ether, polypropylene glycol monoalkyl ether, polyhydric alcohols such as ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, glycerin, acetonitrile, glutarodi Nitrile, methoxyacetonitrile, Pionitoriru, nitrile compounds such as benzonitrile, ethylene carbonate, carbonate compounds such as propylene carbonate, heterocyclic compounds such as 3-methyl-2-oxazolidinone, dimethyl sulfoxide, or the like can be used aprotic polar substances such as sulfolane.

  Further, for the purpose of using a solid (including gel) medium, a polymer may be included. In this case, by adding a polymer such as polyacrylonitrile or polyvinylidene fluoride to the solution-like medium, a polyfunctional monomer having an ethylenically unsaturated group is polymerized in the solution-like medium, thereby solidifying the medium. To.

  In addition to this, the electrolyte 21 does not require a CuI or CuSCN medium, and 2,2 ′, 7,7′-tetrakis (N, N-di-p-methoxyphenylamine) 9,9′-spirobi. A hole transport material such as fluorene can be used.

[Production Method of Photoelectric Conversion Element]
Next, an example of a method for manufacturing the photoelectric conversion element 1 according to the first embodiment of the present technology will be described.

  In the present technology, a method for manufacturing a photoelectric conversion element includes a step of forming a laminate including a photoelectrode layer precursor, an insulating layer precursor, and a catalyst layer precursor, and a step of firing the laminate. The present technology is characterized in that the photoelectrode layer precursor and at least one of the insulating layer precursor and the catalyst layer precursor are made of a green sheet.

(Process for forming the laminate)
"Production of green sheets"
Taking a photoelectrode layer precursor as an example, a method for producing a green sheet will be described.

  First, a slurry as a green sheet forming composition is prepared. The slurry as the green sheet forming composition contains, for example, raw material powder made of semiconductor fine particles such as titanium oxide, a binder and a solvent, and contains a plasticizer and a dispersant as required. Therefore, first, the raw material powder, the binder, the solvent, and the like are weighed and mixed at a predetermined blending ratio. The mixing ratio of the individual materials is appropriately selected depending on, for example, the particle diameter of the raw material powder and the desired viscosity of the slurry. The particle size of the raw material powder made of semiconductor fine particles such as titanium oxide is, for example, about 10 nm to 60 nm. In order to improve the denseness of the photoelectrode layer 3 and to mix metal oxide semiconductor particles having a large particle size as scattering particles, metal oxide semiconductor particles having different particle size distributions are mixed during slurry preparation. May be.

  As the binder, for example, a binder made of an organic material can be used, and specifically, for example, an acrylic resin binder can be used. The solvent is not particularly limited as long as it can disperse the raw material powder and the binder, but it is preferably volatilized in a temperature range lower than the firing temperature of the green sheet. Examples of the solvent include lower alcohols having 4 or less carbon atoms such as methanol, ethanol, isopropanol, n-butanol, sec-butanol, t-butanol, ethylene glycol, propylene glycol (1,3-propanediol), 1, Aliphatic glycols such as 3-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, ketones such as methyl ethyl ketone, dimethylethylamine Such amines can be used alone or in admixture of two or more, but are not particularly limited thereto.

  Next, the mixture of the raw material powder, the binder, the solvent, and the like is sufficiently mixed using, for example, a stirring process, an ultrasonic dispersion process, a bead dispersion process, a kneading process, a homogenizer process, and the like. In order to improve the dispersibility of the raw material powder, the mixing may be performed in several steps.

  Next, the slurry is filtered with a filter to remove foreign matters in the slurry. Next, vacuum defoaming is performed on the filtered slurry to remove internal bubbles. By the above, the slurry as a composition for green sheet formation is obtained.

  Next, for example, the slurry is formed into a sheet by uniformly applying or printing the slurry on the surface of a resin film or the like. As a coating or printing method, it is preferable to use a simple and suitable method for mass production. Examples of coating methods include die coating, micro gravure coating, wire bar coating, direct gravure coating, reverse roll coating, comma coating, knife coating, spray coating, curtain coating, dipping, and spin. A coating method or the like can be used, but is not particularly limited thereto. As a printing method, for example, a relief printing method, an offset printing method, a gravure printing method, an intaglio printing method, a rubber plate printing method, a screen printing method, and the like can be used, but the invention is not particularly limited thereto.

  As shown in FIG. 2A, for example, the slurry 93 is put into a slit coater by a pump 94. The die 95 of the slit coater is disposed so as to face the roll 96, for example. As the roll 96 rotates, the film 99 wound around a part of the peripheral surface of the roll 96 is allowed to travel between the die 95 and the roll 96 at a constant speed. By applying the slurry 93 while running the film 99 at a constant speed, a sheet-like slurry 93 having a substantially uniform thickness can be obtained. The thickness of the slurry 93 to be applied can be adjusted by the gap width of the slit of the die 95 and the film feed speed.

  In order to make it easier to peel off the green sheet later, it is preferable that a release treatment is applied to the surface of the film 99 by applying or printing a composition for imparting peelability in advance. Examples of the composition that imparts releasability include a paint or a silicone resin containing a binder as a main component and added with wax, fluorine, or the like.

  Next, as shown in FIG. 2B, the sheet-like slurry 93 is heated and dried by, for example, heaters 97a, 97b, and 97c. Drying is performed at 100 ° C. for about 5 minutes, and the solvent in the slurry is removed. FIG. 2B shows an example in which the slurry 93 is continuously dried using a plurality of heaters, but the drying method may be either a continuous method or a batch method. After drying, the thickness of the applied slurry is measured by a film thickness measuring device, and the opening and closing of the slit of the die 95 and the gap width of the slit are controlled so that the thickness of the applied slurry is constant. Also good. Thereby, the photoelectrode layer precursor 3p (green sheet) is formed on the film 99.

  Next, as shown in FIG. 2C, the dried photoelectrode layer precursor 3p is cut out together with the film 99 into a predetermined size and shape. The photoelectrode layer precursor 3p and the film 99 can be cut out by punching using, for example, a Pinnacle type or a Thomson type (Bik type). Or it can cut out to a desired shape with a knife or scissors.

  Next, as shown in FIG. 2D, the photoelectrode layer precursor 3p made of a green sheet is obtained by peeling the film 99 from the photoelectrode layer precursor 3p.

  Also for the insulating layer precursor 5p or the catalyst layer precursor 7p, a green sheet can be produced in the same manner as described above. In the production of the insulating layer precursor 5p made of a green sheet, for example, titanium oxide powder having a particle size of 100 nm to 500 nm is used as the raw material powder. In the production of the catalyst layer precursor 7p made of a green sheet, for example, carbon powder is used as the raw material powder.

"Formation of laminated structure"
First, by the method described above, a photoelectrode layer precursor 3p made of a green sheet, an insulating layer precursor 5p made of a green sheet, and a catalyst layer precursor 7p made of a green sheet are prepared. Next, the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p shown in FIGS. By laminating the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p in order and applying a predetermined pressure, as shown in FIG. Can be obtained. Green sheets produced using metal oxide semiconductor fine particles having different particle size distributions may be further laminated.

  In addition, by sequentially forming the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p, a stacked structure similar to the stacked body 11 can be obtained. The lead time can be shortened. That is, the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p can be manufactured on separate lines, and the process flow is simplified by simultaneous processing, and the process and quality control are facilitated. In addition, the laminated body 11 can also be made into a roll shape, as shown to FIG. 3E, and can also be supplied as a raw material for manufacture of a photoelectric conversion element or a photoelectrode material.

  Further, in order to improve the power generation efficiency of the photoelectric conversion element, for example, when a light diffusion layer for taking in more light on the light incident side and diffusing more light is provided in the photoelectric conversion element, the green sheet is also used. A desired structure can be easily realized by laminating a plurality of sheets. For example, a titanium sheet having a different particle size may be used to produce a green sheet that serves as a diffusion layer precursor, and the green sheet may be overlapped with a green sheet such as a photoelectrode layer precursor.

  Next, as shown in FIG. 3F, the laminate 11 is bonded to the conductive base material 9 such as a metal or a transparent conductive film so that the catalyst layer precursor 7p is disposed on the conductive base material 9 side. The laminate 11 is bonded to the conductive substrate 9 only by applying the pressure P1 by overlapping the conductive substrate 9 and the laminate 11, and the method of applying the pressure P1 to the conductive substrate 9 and the laminate 11, It is not particularly limited, such as a surface press, a roll press (line press), or a hydraulic press. The laminate 11 can be bonded to the conductive substrate 9 by, for example, pressure bonding using a press device. Examples of the press device include, but are not limited to, a flat plate press device, a calendar press device (roll press device), and a hot press device. The pressure P1 corresponding to the press pressure is set to, for example, about 1 MPa to 100 MPa, but various conditions such as the press pressure, the press time, and the press temperature may be determined by performing various tests.

  There is no restriction | limiting in particular in the thickness of the electrically conductive base material 9, For example, the titanium foil etc. about 30 micrometers thick can be used. The conductive substrate 9 also has a function as a support substrate for securing the strength of the green sheet after firing.

  FIG. 4A shows a state where the conductive base material 9 and the laminate 11 are bonded together. As shown in FIG. 4A, the laminate 12 is configured by laminating a catalyst layer precursor 7p, an insulating layer precursor 5p, and a photoelectrode layer precursor 3p in this order on one main surface of the conductive substrate 9. The laminated body 12 can be used as a photoelectrode material of a photoelectric conversion element, for example. When the conductive substrate 9 has flexibility, the laminated body 12 can also be formed in a roll shape, like the laminated body 11 shown in FIG. 3E, and supplied as a raw material for manufacturing a photoelectric conversion element. You can also

(Baking process)
Next, a firing process is performed on the laminate 12. Firing of the laminate 12 can be performed using a batch-type firing furnace or a continuous-type firing furnace. Firing is performed, for example, under conditions of about 500 ° C. for about 30 minutes. By performing the firing process on the laminate 12, the binder and the plasticizer in the green sheet are removed, and necking occurs between the semiconductor fine particles in the photoelectrode layer 3, thereby improving the electronic connection between the semiconductor fine particles. To do. According to the present technology, it is not necessary to perform the baking step in a low temperature region where a polymer resin substrate such as a polymer film can be used, and the photoelectric conversion efficiency of the photoelectric conversion element does not decrease.

(Dye support)
Next, a sensitizing dye is dissolved in a solvent to prepare a solution. In order to dissolve the sensitizing dye, heating, addition of a dissolution aid, and filtration of insoluble matter may be performed as necessary. The solvent is preferably a solvent capable of dissolving the sensitizing dye and capable of mediating dye adsorption on the porous semiconductor layer obtained by firing the photoelectrode layer precursor 3p. For example, ethanol, Alcohol solvents such as isopropyl alcohol and benzyl alcohol, nitrile solvents such as acetonitrile and propionitrile, halogen solvents such as chloroform, dichloromethane and chlorobenzene, ether solvents such as diethyl ether and tetrahydrofuran, ethyl acetate and butyl acetate Ester solvents, ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone, carbonate solvents such as diethyl carbonate and propylene carbonate, carbohydrate solvents such as hexane, octane, toluene and xylene, dimethylformamide Dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl imidazolinone, N-methylpyrrolidone, water and the like can be used alone or in combination, but is not limited thereto.

  Next, for example, the fired body of the laminate 12 is immersed in a solution containing a sensitizing dye, whereby the sensitizing dye is supported on the metal oxide fine particles. Utilizing the affinity of the linked substituents of the sensitizing dye by immersing the porous semiconductor layer obtained by firing the photoelectrode layer precursor 3p together with the fired body of the laminate 12 in a solution containing the sensitizing dye Thus, the sensitizing dye can be brought into contact with and bonded to the porous surface of the porous semiconductor. Of course, the method for supporting the sensitizing dye is not limited to this method. In this way, a laminate 14 in which a laminate 13 composed of the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7 is formed on one main surface of the conductive substrate 9 can be obtained.

(Formation of conductive substrate)
Next, as shown to FIG. 4C, the electroconductive base material used as the light-incidence side of a photoelectric conversion element is prepared. The conductive substrate includes, for example, a substrate 17 and a transparent conductive layer 15 formed on one main surface of the substrate 17. For example, a plate-like or film-like substrate 17 is formed using a melt extrusion method, an injection molding method, or the like, and then the transparent conductive layer 15 is formed on the substrate 17 by a thin film manufacturing technique such as a sputtering method. .

(Lamination of laminate and conductive substrate)
Next, as shown in FIG. 4D, the laminate 14 and a conductive base material composed of the base material 17 and the transparent conductive layer 15 are bonded together. The laminated body 14 is bonded to the conductive base material composed of the base material 17 and the transparent conductive layer 15 only by superposing the conductive base material and the laminated body 14 and applying the pressure P2. The method of applying the pressure P2 to the conductive substrate and the laminate 14 is not particularly limited, such as a surface press, a roll press (line press), or a hydraulic press. The laminate 14 can be bonded to the conductive substrate by, for example, pressure bonding using a press device. Examples of the press device include, but are not limited to, a flat plate press device, a calendar press device (roll press device), and a hot press device. The pressure P2 corresponding to the press pressure is set to, for example, about 1 MPa to 100 MPa, but various conditions such as the press pressure, the press time, and the press temperature may be determined by performing various tests. When the conductive base material and the laminate 14 are bonded together, the conductive base material may be heated in order to improve adhesion.

(Filling with electrolyte)
Next, as shown in FIG. 5A, a sealing material 19 is disposed between the conductive base material 9 and the transparent conductive layer 15. The sealing material 19 is disposed on the periphery of the conductive base material 9 or the transparent conductive layer 15. An ultraviolet curable adhesive as a sealing material 19 is formed in advance on the periphery of the conductive base material 9 by screen printing or the like, and the conductive base material 9 and the transparent conductive layer 15 are interposed via the ultraviolet curable adhesive. May be pasted together. Thus, a space filled with the electrolytic solution 21 is formed by the conductive base material 9, the transparent conductive layer 15, and the sealing material 19.

  Next, an electrolytic solution is injected into this space from, for example, an injection port formed in advance in the conductive base material 9, and the space is filled with the electrolytic solution. In this case, a method using a capillary phenomenon by dropping several drops of the electrolytic solution at the inlet is simple. The method for injecting the electrolytic solution is not particularly limited, but a method in which the peripheral edge (outer peripheral portion) is sealed in advance and the electrolytic solution is injected into the photoelectric conversion element from the injection port under reduced pressure is preferable. Thereafter, the inlet is closed. Thereby, the target photoelectric conversion element 1 shown in FIG. 5B is manufactured. The sealing material 19 is disposed leaving only a part of the peripheral edge (outer peripheral portion), and the portion where the sealing material 19 is not disposed is used as an injection port, and the electrolytic solution is introduced into the photoelectric conversion element from the injection port. Injection may be performed, and then the injection port may be sealed under reduced pressure.

  Considering the heat resistance of the resin base material, it is difficult to add an additive such as a binder or a plasticizer in the method of obtaining a porous semiconductor layer by firing a dispersion paste at a firing temperature of about 150 ° C. or less. It is necessary to develop a dispersion paste that reduces the content of organic substances such as However, in the case of preparing a dispersion paste with the organic content reduced as much as possible, it is difficult to adjust the viscosity. In addition, the dispersion paste after preparation has a low viscosity, and dispersion coating thickness tends to vary in the application of dispersion paste, so screen printing and other methods cannot be used. Mainly the blade method, spray method, and spin method I have to use. When using a blade method, a spray method, a spin method, or the like, a process for patterning the mixing ratio of the material of the dispersion paste is also required. For this reason, the process man-hours and the manufacturing costs for preparing the dispersion paste are increased, which hinders the reduction of the manufacturing costs of the dye-sensitized solar cells.

  According to the present technology, since the photoelectrode layer 3 and at least one of the insulating layer 5 and the catalyst layer 7 are fired bodies of the green sheet, the photoelectrode layer precursor 3p is fired at a high temperature. Can do. Accordingly, since firing at a low temperature does not result in insufficient necking, a decrease in connectivity between titanium oxide particles is suppressed, and a decrease in conversion efficiency and durability of the dye-sensitized solar cell can be prevented. In addition, it is possible to replace glass, which is the main component of material costs in the production of dye-sensitized solar cells, with a relatively inexpensive polymer resin substrate.

  In the conventional technique, the sintered titanium oxide porous layer becomes very brittle due to the removal of the binder and the like, making it difficult to transfer it onto the substrate to be transferred. A base material can be used as a support base material, and handling of the fired body of a green sheet is easy. Moreover, a green sheet fired body, a transparent conductive layer and a polymer resin base material laminate can be obtained simply by pressing the green sheet fired body on the polymer resin base material on which the transparent conductive layer is formed. .

  According to the present technology, it is possible to easily obtain a laminated structure such as a photoelectrode layer only by applying a pressure by superposing a plurality of different types of green sheets. In addition, the green sheet can be easily processed into various shapes, and can cope with, for example, increasing the thickness of the photoelectrode layer or the like and increasing the size of the dye-sensitized solar cell.

[Another example of manufacturing method of photoelectric conversion element]
The green sheet can be processed into various shapes, and due to its flexibility, the photoelectrode layer and the like can be formed into a curved surface as a whole.

  For example, as shown in FIGS. 6A to 6D, a photoelectrode layer precursor 3p made of a green sheet, an insulating layer precursor 5p made of a green sheet, and a catalyst layer precursor 7p made of a green sheet are produced by the method described above. . Next, the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p are sequentially superposed and a predetermined pressure is applied, thereby obtaining a laminate 11 in which these are integrally configured.

  Next, as shown in FIG. 6E, the laminate 11 is bonded to the conductive base material 9. At this time, the laminated body 12 is curved by bonding the laminated body 11 to the conductive base material 9 on a support base having a curved shape or after the laminated body 11 is bonded to the conductive base material 9. Thereby, the laminated body 12 can be made into a curved surface shape as a whole. Next, as shown in FIG. 6F, a curved laminate 14 can be obtained by firing the laminate 12. In this case, the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7 are also layers having curved surfaces as a whole.

  Next, as shown to FIG. 7A, the electroconductive base material used as the light-incidence side of a photoelectric conversion element is prepared. At this time, a substrate having a shape corresponding to the curved surface shape of the laminate 14 can be used as the substrate 17, and the transparent conductive layer 15 formed on one main surface of the substrate 17 is also the laminate 14. It can be made into the shape corresponding to the curved surface shape.

  Next, as shown in FIG. 7B to FIG. 7D, the laminate 14 and the conductive base material composed of the base material 17 and the transparent conductive layer 15 are bonded together, and after the sealing material 19 is disposed, the electrolytic solution is added. By filling, the photoelectric conversion element 31 having a curved surface shape as a whole is obtained. If the curved surface shape of the photoelectric conversion element 31 is designed according to, for example, a building or structure having a curved surface shape, the photoelectric conversion element 31 can be easily installed on the building or structure having a curved surface shape. .

<2. Second Embodiment>
[Configuration of photoelectric conversion element]
FIG. 8A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion element according to the second embodiment of the present technology. As shown in FIG. 8A, the photoelectric conversion element 71 according to the second embodiment is common to the first embodiment in that it includes a stacked body 13 of the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7. Also in the second embodiment, the photoelectrode layer 3 is a green sheet fired body, and at least one of the insulating layer 5 and the catalyst layer 7 is a green sheet fired body. In the second embodiment, the laminate 13 is interposed between the conductive base material 39 and the transparent conductive layer 15 a, and the conductive base material 39 is formed on one main surface of the base material 17. It is different from the first embodiment in that it is electrically connected. Moreover, the photoelectric conversion element 71 is different from the first embodiment in that the sealing material 19 is not provided and the electrolytic solution 21 is sealed by the lamination film 27. A photoelectric conversion element 71 illustrated in FIG. 8A is a photoelectric conversion element having a so-called monolithic structure in which a positive electrode and a negative electrode are formed on a single substrate.

[Production Method of Photoelectric Conversion Element]
Next, an example of a method for manufacturing the photoelectric conversion element 71 according to the second embodiment of the present technology will be described with reference to FIGS. 8B to 8D and FIGS. 9A to 9C.

  First, the slurry as a composition for green sheet formation is prepared like the case of the photoelectric conversion element 1 which concerns on 1st Embodiment. Next, after applying or printing the slurry uniformly, the sheet-like slurry is dried by heating to produce a green sheet. Next, the green sheet is cut into a predetermined size and shape to produce a photoelectrode layer precursor 3p. Similarly, the insulating layer precursor 5p and the catalyst layer precursor 7p are produced.

  Next, similarly to the case of the photoelectric conversion element 1 according to the first embodiment, a stacked body 11 of the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p is manufactured, and a press device or the like. Thus, the laminate 11 is bonded to the conductive base material 39. In addition, as a material of the conductive base material 39, it is preferable to select a material having low reactivity with the electrolytic solution 21. As a material of the conductive base material 39, for example, a metal can be used, but is not limited thereto. As the metal, for example, one or more selected from the group consisting of titanium, tungsten, molybdenum, tantalum, niobium, zirconium, zinc, nickel, chromium, and iron can be used. Specifically, for example, as the metal, for example, a simple substance such as titanium, tungsten, molybdenum, tantalum, niobium, zirconium, zinc, nickel, chromium, iron, or an alloy containing two or more of these can be given. As the alloy, nickel alloys such as stainless steel (SUS), NiCu alloy, NiCr alloy, etc. are preferably used. As stainless steel, it is preferable to use SUS304, SUS304L, SUS310S, SUS316, SUS316L, SUS317L, SUS321, SUS347, or the like. In order to protect the conductive base material 39 from the electrolytic solution 21, for example, the conductive base material 39 may be covered with a resin material or the like. The conductive base material 39 preferably has flexibility, and the thickness of the conductive base material 39 is preferably 30 μm or more from the viewpoint of using the conductive base material 39 as a support base material for a green sheet fired body. preferable.

  Next, a baking process is performed with respect to the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p. Firing on the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the catalyst layer precursor 7p is performed, for example, under conditions of about 500 ° C. for about 30 minutes. After the firing treatment, the laminate of the photoelectrode layer precursor 3p, the insulating layer precursor 5p and the catalyst layer precursor 7p and the conductive substrate 39 is immersed in a solution containing a sensitizing dye, and metal oxide fine particles A sensitizing dye is supported on the surface.

  Next, as shown in FIG. 8B, the transparent conductive layer 15 is formed on one main surface of the base material 17 by a thin film manufacturing technique such as sputtering, and a conductive base material that becomes the light incident side of the photoelectric conversion element is formed. prepare. Next, as shown in FIG. 8C, the transparent conductive layer 15 is separated into a negative electrode side transparent conductive layer 15a and a positive electrode side transparent conductive layer 15b by etching, laser processing, polishing, or the like. The transparent conductive layer 15 may be patterned in advance using a mask or the like to form the negative electrode side transparent conductive layer 15a and the positive electrode side transparent conductive layer 15b.

  Next, as shown in FIG. 8D, a conductive substrate composed of a laminate 34 of the photoelectrode layer 3, the insulating layer 5 and the catalyst layer 7 and the conductive substrate 39, the substrate 17 and the transparent conductive layer 15, Paste together. The laminated body 34 is bonded to the conductive base material composed of the base material 17 and the transparent conductive layer 15 only by superposing the conductive base material and the laminated body 34 and applying the pressure P2. The pressure P2 is set to about 1 MPa to 100 MPa, for example. When the conductive base material and the laminate 34 are bonded together, the conductive base material may be heated in order to improve adhesion.

  Next, as shown in FIG. 9A, the conductive base material 39 and the positive electrode side transparent conductive layer 15b are electrically connected. The connection method is not particularly limited, such as adhesion using an electrically conductive adhesive, welding, or soldering, and may be appropriately selected in consideration of the heat resistance of the base material 17.

  Next, as shown in FIG. 9B, an electrolytic solution 21 is sealed using a lamination film made of a resin material or the like. Thus, the photoelectric conversion element 71 illustrated in FIG. 9C is obtained.

  By adopting the monolithic structure, it is possible to reduce the amount of glass used as the main component of the material cost, and to suppress the manufacturing cost of the photoelectric conversion element. According to the present technology, in the manufacturing process of the photoelectric conversion element having a monolithic structure, it is not necessary to sequentially form a plurality of layers from the lower layer in order to form a stacked structure, and therefore the lead time can be shortened. . In addition, each layer of the stacked structure can be formed without using a method such as a screen printing method in which variations in film thickness distribution tend to occur.

<3. Third Embodiment>
[Configuration of photoelectric conversion element]
FIG. 10A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion element according to a third embodiment of the present technology. As shown in FIG. 10A, the photoelectric conversion element 81 according to the third embodiment includes a photoelectrode layer 3, an insulating layer 5, a catalyst layer 7, and a collecting electrode 44. The collecting electrode 44 is interposed between the photoelectrode layer 3 and the insulating layer 5. The catalyst layer 7 is formed, for example, on one main surface of the conductive base material 49, and includes a laminate of the photoelectrode layer 3, the collecting electrode 44, the insulating layer 5, the catalyst layer 7, and the conductive base material 49, and electrolysis. The liquid 21 is sealed with a lamination film 28.

  The third embodiment is common to the second embodiment in that the photoelectrode layer 3 and at least one of the insulating layer 5 and the catalyst layer 7 are used as a green sheet fired body. Further, the third embodiment is common to the second embodiment in that the photoelectrode layer 3, the insulating layer 5, the catalyst layer 7, the conductive base material, and the electrolytic solution 21 are sealed with a lamination film. To do. Here, in the third embodiment, the current collector electrode 44 is interposed between the photoelectrode layer 3 and the insulating layer 5, and the second embodiment is not provided with a transparent conductive layer on the substrate 17. Is different. The photoelectric conversion element 81 shown in FIG. 10A is a photoelectric conversion element having a so-called TCO-free (Transparent Conductive Oxide-free) structure that does not require a transparent conductive layer on the light-incident substrate.

[Production Method of Photoelectric Conversion Element]
Next, an example of a method for manufacturing the photoelectric conversion element 81 according to the third embodiment of the present technology will be described with reference to FIGS. 10B to 10D and FIGS. 11A to 11D.

  First, the slurry as a composition for green sheet formation is prepared like the case of the photoelectric conversion element 1 which concerns on 1st Embodiment. Next, after applying or printing the slurry uniformly, the sheet-like slurry is dried by heating to produce a green sheet. Next, the green sheet is cut into a predetermined size and shape to produce a photoelectrode layer precursor 3p.

  Next, similarly to the case of the photoelectric conversion element 1 according to the first embodiment, as shown in FIG. 10B, the photoelectrode layer precursor 3p is formed on one main surface of the current collecting electrode 44 by a press device or the like. to paste together. Bonding of the photoelectrode layer precursor 3p to the current collecting electrode 44 may be performed only by applying the pressure P4 while superposing the current collecting electrode 44 and the photoelectrode layer precursor 3p. The pressure P4 is set to about 1 MPa to 100 MPa, for example. Hereinafter, in the current collecting electrode 44, the surface on which the photoelectrode layer precursor 3p is attached is referred to as S1, and the surface opposite to the surface S1 is referred to as surface S2.

  As the material of the current collecting electrode 44, a porous material having excellent conductivity is preferably used. For example, the same material as the conductive base material 39 of the third embodiment can be used. As the structure of the current collecting electrode 44, for example, when the electrolytic solution is hung on the surface of the current collecting electrode 44, a structure in which the electrolytic solution penetrates in the electrode depth direction and can reach the back surface side is preferable. For example, a film with a hole, a sheet, a foil, a substrate, or the like can be used. More specifically, a foil (for example, plain weave, twill weave, plain tatami mat, twill mat weave, etc.), porous body, non-woven fabric, fiber sintered body, expanded metal, punching metal, foil with holes made by etching, etc. However, it is not limited to these. As the current collecting electrode 44, a surface of a base material made of a plastic material or the like covered with a conductive material such as a metal may be used. The thickness of the current collecting electrode 44 is preferably 30 μm or more from the viewpoint of using the current collecting electrode 44 as a supporting base material for the green sheet fired body. Further, considering that ions in the electrolytic solution move efficiently and the movement of electrons associated therewith is not inhibited, for example, the thickness is preferably 100 μm or less.

  Next, as in the case of the photoelectrode layer precursor 3p, an insulating layer precursor 5p made of a green sheet and a catalyst layer precursor 7p made of a green sheet are produced.

  Next, as shown in FIG. 10C, the laminated body of the insulating layer precursor 5p and the catalyst layer precursor 7p and the conductive base material by a press device or the like so that the catalyst layer precursor 7p is in contact with the conductive base material 49. 49 and pasted together. The laminated body of the insulating layer precursor 5p and the catalyst layer precursor 7p to the conductive base material 49 is formed by superposing the laminated body of the conductive base material 49 and the insulating layer precursor 5p and the catalyst layer precursor 7p on the pressure P5. Just add. The pressure P5 is set to about 1 MPa to 100 MPa, for example. Note that the catalyst layer precursor 7p and the insulating layer precursor 5p may be sequentially bonded to the conductive base material 49. Hereinafter, the exposed surface of the insulating layer precursor 5p is referred to as S3.

  Next, as shown in FIG. 10D, the stacked body of the collector electrode 44 and the photoelectrode layer precursor 3p, the insulating layer precursor 5p, and the insulating layer precursor 5p with a pressing device or the like so that the surfaces S3 and S2 face each other. The catalyst layer precursor 7p and the laminate of the conductive base material 49 are bonded together. For the bonding, it is only necessary to superimpose the respective laminates and apply the pressure P6. The pressure P6 is set to about 1 MPa to 100 MPa, for example. In addition, before bonding, a metal foil for wiring extraction made of titanium or titanium subjected to surface treatment may be attached to each of the collecting electrode 44 and the conductive base material 49. As a method of connecting the metal foil for taking out the wiring, it can be performed by adhesion, welding, soldering, or the like using a conductive adhesive. As a result, as shown in FIG. 11A, a laminated body 42 in which the photoelectrode layer precursor 3p, the collector electrode 44, the insulating layer precursor 5p, the catalyst layer precursor 7p, and the conductive base material 49 are integrally formed is obtained. It is done.

  Next, a firing process is performed on the stacked body 42. Firing on the stacked body 42 is performed, for example, under conditions of about 500 ° C. for about 30 minutes. After the firing treatment, the laminate 42 is immersed in a solution containing a sensitizing dye, and the sensitizing dye is supported on the metal oxide fine particles. As a result, as shown in FIG. 11B, a laminate 43 in which the photoelectrode layer 3, the collecting electrode 44, the insulating layer 5, the catalyst layer 7 and the conductive base material 49 are integrally formed is obtained.

  Next, as shown in FIG. 11C, the laminate 43 is sealed with the base material 17 and the lamination film 28. In the third embodiment, since it is not necessary to form a transparent conductive layer on the base material 17, a transparent film or the like can be used as the base material 17, and the photoelectric conversion element can be reduced in size and weight. It is also easy to configure. At this time, as a terminal for connection to the outside, sealing is performed so that a part of the collecting electrode 44 and a part of the conductive base material 49 or a metal foil for wiring extraction is outside the lamination film 28. Done. At this time, part of the base material 17 and the lamination film 28 is not sealed so that the electrolyte solution 21 can be easily injected.

  Next, after injecting the electrolytic solution 21, a part of the base material 17 and the lamination film 28 which are not sealed is sealed. Thus, the photoelectric conversion element 81 illustrated in FIG. 11D is obtained. According to the third embodiment, the same effects as those of the second embodiment can be obtained.

<4. Fourth Embodiment>
[Configuration of photoelectric conversion module]
FIG. 12A is a schematic cross-sectional view illustrating an example of a configuration of a photoelectric conversion module according to the fourth embodiment of the present technology. As shown in FIG. 12A, the photoelectric conversion module 91 is configured by electrically connecting a plurality of photoelectric conversion elements according to the first embodiment.

  In the photoelectric conversion module 91 shown in FIG. 12A, for example, the photoelectric conversion element 1 a and the photoelectric conversion element 1 b sharing the substrate 17 are electrically connected via the conductive member 30. The conductive member 30 is made of, for example, metal wiring or conductive paste, but is not limited thereto as long as it has conductivity. As shown in FIG. 12A, the photoelectric conversion module 91 is provided with a support base material 10 such as glass or resin as necessary. At this time, the photoelectric conversion element 1 a and the photoelectric conversion element 1 b are disposed on the support base material 10.

[First Modification of Photoelectric Conversion Module]
FIG. 12B is a schematic cross-sectional view illustrating a first modification of the configuration of the photoelectric conversion module according to the fourth embodiment of the present technology. As illustrated in FIG. 12B, the photoelectric conversion module 101 is configured by electrically connecting a plurality of photoelectric conversion elements according to the second embodiment. In the photoelectric conversion module 101 illustrated in FIG. 12B, for example, the conductive base material 39 a is connected to the transparent conductive layer 15 b, whereby the photoelectric conversion element 71 a and the photoelectric conversion element 71 b sharing the substrate 17 are electrically connected. The

[Second Modification of Photoelectric Conversion Module]
FIG. 12C is a schematic cross-sectional view illustrating a second modification example of the configuration of the photoelectric conversion module according to the fourth embodiment of the present technology. As shown in FIG. 12C, the photoelectric conversion module 111 is configured by electrically connecting a plurality of photoelectric conversion elements according to the third embodiment. In the photoelectric conversion module 111 shown in FIG. 12C, for example, the current collecting electrode 44a and the conductive base material 49b are connected via the conductive member 40, whereby the photoelectric conversion element 81a and the photoelectric conversion element 81b sharing the substrate 17 are used. Are electrically connected.

  According to the fourth embodiment, since it is not necessary to pattern the photoelectrode layer or the like and form it on the substrate, the photoelectric conversion module can be manufactured without requiring a complicated process.

[Third Modification of Photoelectric Conversion Module]
A plurality of laminates composed of the photoelectrode layer 3, the insulating layer 5, the catalyst layer 7, and the like may be sealed with a laminate film or the like. FIG. 13A is a schematic cross-sectional view illustrating an example of a photoelectric conversion module in which a plurality of stacked layers of a photoelectrode layer, an insulating layer, a catalyst layer, and a conductive base material are sealed. In the photoelectric conversion module 121 shown in FIG. 13A, the conductive base material 39a is connected to the transparent conductive layer 15b, so that the laminate composed of the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7 is connected in series.

[Fourth Modification of Photoelectric Conversion Module]
FIG. 13B is a schematic cross-sectional view illustrating an example of a photoelectric conversion module in which a plurality of stacked bodies of a photoelectrode layer, a collecting electrode, an insulating layer, a catalyst layer, and a conductive base material are sealed. In the photoelectric conversion module 131 shown in FIG. 13B, a photoelectrode layer of one stacked body and a catalyst layer of a stacked body different from the stacked body are connected through a conductive member 46.

  The electromotive force per photoelectric conversion module can be increased by sealing a plurality of laminates including the photoelectrode layer 3, the insulating layer 5, and the catalyst layer 7 with a laminate film or the like. A plurality of photoelectric conversion modules 121 shown in FIG. 13A or a plurality of photoelectric conversion modules 131 shown in FIG. 13B may be further connected.

In addition, this technique can also take the following structures.
(1)
A laminate of a photoelectrode layer, an insulating layer and a catalyst layer;
A conductive substrate;
A transparent conductive layer, and
The laminate is interposed between the conductive substrate and the transparent conductive layer,
The photoelectric conversion element, wherein the photoelectrode layer and at least one of the insulating layer and the catalyst layer are a fired body of a green sheet.
(2)
The said laminated body is a photoelectric conversion element as described in (1) interposed between the said conductive base material and the said transparent conductive layer so that the said catalyst layer may be arrange | positioned at the said conductive base side.
(3)
The said electroconductive base material is a photoelectric conversion element as described in (1) or (2) which has flexibility.
(4)
A resin base material having flexibility;
The said transparent conductive layer is a photoelectric conversion element in any one of (1)-(3) formed on the said resin base material.
(5)
A photoelectrode layer;
An insulating layer;
A catalyst layer;
A collecting electrode, and
The current collecting electrode is interposed between the photoelectrode layer and the insulating layer,
The catalyst layer is provided on one main surface of the insulating layer,
The photoelectric conversion element, wherein the photoelectrode layer and at least one of the insulating layer and the catalyst layer are a fired body of a green sheet.
(6)
The photoelectric conversion element according to any one of (1) to (5), wherein the photoelectrode layer, the insulating layer, and the catalyst layer are green sheet fired bodies.
(7)
The photoelectric conversion element according to any one of (1) to (6), wherein the photoelectrode layer is a porous semiconductor layer containing semiconductor fine particles, and the semiconductor fine particles are necked.
(8)
A photoelectric conversion module in which a plurality of the photoelectric conversion elements according to any one of (1) to (7) are electrically connected.
(9)
Forming a laminate composed of a photoelectrode layer precursor, an insulating layer precursor and a catalyst layer precursor on one main surface of the conductive substrate;
And firing the laminate.
The said photoelectrode layer precursor and at least one of the said insulating layer precursor and the said catalyst layer precursor are manufacturing methods of the photoelectric conversion element which consists of a green sheet.
(10)
And further comprising a step of bonding the fired body of the laminate and the transparent conductive layer,
The process for producing a photoelectric conversion element according to (9), wherein the fired body of the laminate and the transparent conductive layer are bonded together by pressure bonding.
(11)
The method for producing a photoelectric conversion element according to (9) or (10), further comprising a step of bonding the laminate to the conductive substrate.
(12)
Forming a photoelectrode layer precursor on one main surface of the collecting electrode;
Forming an insulating layer precursor and a catalyst layer precursor on one main surface of the conductive substrate;
The other main surface of the current collecting electrode and the insulating layer precursor are bonded to face each other, the current collecting electrode on which the photoelectrode layer precursor is formed, the insulating layer precursor and the catalyst layer precursor are Forming a laminate in which the formed conductive base material is integrated; and
And firing the laminate.
The said photoelectrode layer precursor and at least one of the said insulating layer precursor and the said catalyst layer precursor are manufacturing methods of the photoelectric conversion element which consists of a green sheet.
(13)
A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
A laminate in which the catalyst layer precursor, the insulating layer precursor, and the photoelectrode layer precursor are sequentially laminated.
(14)
A conductive substrate;
A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
A photoelectrode material in which the catalyst layer precursor, the insulating layer precursor, and the photoelectrode layer precursor are sequentially laminated on one main surface of the conductive substrate.

  A photoelectric conversion element in which a photoelectrode layer is formed from a fired body of a green sheet and a photoelectric conversion element in which a photoelectrode layer is formed from a fired body of a precursor formed by a spray method are manufactured. The electrical characteristics of were evaluated. Hereinafter, the present technology will be specifically described by way of examples. However, the present technology is not limited only to these examples.

<Sample 1>
Hereinafter, the manufacturing process of the photoelectric conversion element of Sample 1 will be described. Sample 1 is a reference example in which a photoelectrode layer is formed from a fired green sheet.

First, after mixing the following materials, the slurry for forming a photoelectrode layer precursor was prepared by performing a dispersion process using a bead disperser.
Titanium oxide fine particles: Aerosil (registered trademark of Evonik Degussa GmbH) P-25 (particle size: 20 nm)
Solvent: Methyl ethyl ketone and ethanol Dispersant: Mariim (registered trademark) AFB-1521 (weight average molecular weight: 30,000) manufactured by NOF Corporation
Binder: Mixture of acrylic resin and methyl ethyl ketone (MEK) solvent Plasticizer: Dibutyl phthalate

  Next, filtration with a filter and vacuum defoaming were performed on the prepared slurry, and the slurry was uniformly applied or printed on the surface of the resin film subjected to the mold release treatment. Next, the sheet-like slurry was dried by heating, and then cut out to a size of 5 mm □ to obtain a green sheet as a photoelectrode layer precursor.

  Next, the green sheet was baked under conditions of 510 ° C. for 30 minutes.

Next, a glass substrate having an FTO layer as a transparent conductive layer formed on one main surface by a CVD method is prepared, and the organic material on the surface of the transparent conductive layer is formed on the glass substrate on which the transparent conductive layer is formed. For removal, ultraviolet irradiation treatment and ozone (O ₃ ) treatment were performed for 10 minutes.

  Next, the fired photoelectrode layer precursor was bonded to the glass substrate on which the transparent conductive layer was formed by a small flat plate press. At this time, the press pressure was set to 1 MPa.

Next, the sensitizing dye is supported on the metal oxide fine particles by immersing the laminate of the fired photoelectrode layer precursor and the glass substrate on which the transparent conductive layer is formed in an N719 solution for 2 days, A laminate of a photoelectrode layer, a transparent conductive layer and a glass substrate was obtained. Below, the structure of N719 solution is shown.
Solute: N719 0.3 mM
Solvent: tert-butyl alcohol and acetonitrile (weight ratio 1: 1)

Next, an electrolytic solution was prepared and immersed for 5 minutes in the prepared electrolytic solution of a photoelectrode layer, a transparent conductive layer and a glass substrate. Below, the structure of electrolyte solution is shown.
Solute: Sodium iodide (NaI) 0.05M, 1- propyl-2,3-dimethyl imidazolium iodide (DMPImI) 0.7M, iodine (I ₂₎ 0.1M and tert- butylpyridine 0.1M
Solvent: Methoxypropionitrile

  Next, a glass substrate having an FTO layer formed on one main surface was prepared, and a catalyst layer made of carbon was formed on the surface of the FTO layer by screen printing.

  Next, with the photoelectrode layer and the catalyst layer facing each other, a laminate of the photoelectrode layer, the transparent conductive layer, and the glass substrate, and a laminate of the catalyst layer, the FTO layer, and the glass substrate are formed with a thickness of 30 μm. It bonded together through the spacer of the silicon resin. Thus, a photoelectric conversion element of Sample 1 was obtained.

<Sample 2>
Sample 1 except that a photoelectrode layer was prepared by preparing a dispersion for forming a photoelectrode layer on a glass substrate on which an FTO layer was formed and applying the dispersion by a spray method, followed by firing treatment. In the same manner as in the case, a photoelectric conversion element of Sample 2 was obtained.

[Evaluation of photoelectric conversion element]
First, the photoelectric conversion efficiency of the photoelectric conversion elements of Sample 1 and Sample 2 was measured using a solar simulator manufactured by Yamashita Denso Co., Ltd.

14A is a graph showing the measurement results of photoelectric conversion efficiency for the photoelectric conversion elements of Sample 1 and Sample 2. FIG. FIG. 14A is a graph with the current density [mA / cm ² ] on the vertical axis and the voltage [V] on the horizontal axis. In FIG. 14A, the measurement result for sample 1 is shown by L1, and the measurement result for sample 2 is shown by L2.

  Next, the electrical characteristics of the photoelectric conversion elements of Sample 1 and Sample 2 were measured by the AC impedance method.

  FIG. 14B is a graph showing measurement results of electrical characteristics of the photoelectric conversion elements of Sample 1 and Sample 2. FIG. 14B is a complex impedance plot (also called Cole-Cole Plot or Nyquist plot) in which the real component of the measured impedance Z is plotted on the horizontal axis and the imaginary component is plotted on the vertical axis. In FIG. 14B, the measurement result for sample 1 is indicated by L3, and the measurement result for sample 2 is indicated by L4.

Table 1 below shows the measurement result of photoelectric conversion efficiency and the measurement result of electrical characteristics of Sample 1 and Sample 2 by light irradiation of AM1.5G. In Table 1, Voc [V], Jsc [mA / cm ² ], FF [%], Eff. [%] And Rs. [Ω] represents the open-circuit voltage, short-circuit current density, fill factor, photoelectric conversion efficiency, and series resistance of the photoelectric conversion element, respectively.

  14A and 14B and Table 1 revealed the following. Even when the photoelectrode layer is constituted by a green sheet fired body, it is equivalent to the case where the photoelectrode layer is constituted by applying a dispersion for forming a photoelectrode layer and performing a firing treatment. It was found that photoelectric conversion efficiency can be obtained. Furthermore, from the measurement results of the electrical characteristics, it was found that there is no difference in the electrical characteristics of the photoelectrode layer and the adhesion of the photoelectrode layer.

  As described above, according to the present technology, since a green sheet that is easy to handle is used as at least a precursor of the photoelectrode layer, the photoelectrode layer and the polymer resin base material are bonded together after the baking treatment. It can be carried out. In addition, the manufacturing process can be simplified, and the capital investment and lead time can be reduced by simultaneous processing. Furthermore, since the photoelectrode layer, the insulating layer, or the catalyst layer can be formed thick, a laminated structure of the photoelectrode layer, the insulating layer, and the catalyst layer can be easily realized. Therefore, according to the present technology, it is possible to provide a photoelectric conversion element that can use a polymer resin base material as a base material without complicating the process, a manufacturing method thereof, a photoelectric conversion module, a laminate, and a photoelectrode material. Can do.

  The present technology is not limited to the above-described embodiments of the present technology, and various modifications and applications are possible without departing from the gist of the present technology.

  For example, the configurations, methods, steps, shapes, materials, numerical values, and the like given in the above-described embodiments and examples are merely examples, and different configurations, methods, steps, shapes, materials, numerical values, and the like are necessary as necessary. May be used.

  The configurations, methods, processes, shapes, materials, numerical values, and the like of the above-described embodiments can be combined with each other without departing from the gist of the present technology.

1, 31, 71, 81 Photoelectric conversion element 3 Photoelectrode layer 5 Insulating layer 7 Catalyst layer 3p Photoelectrode layer precursor 5p Insulating layer precursor 7p Catalyst layer precursor 9 Conductive substrate 11, 12, 14, 34, 42, 43 Laminated body 15 Transparent conductive layer 17 Base material 39, 49 Conductive base material 44 Current collecting electrode 91, 101, 111, 121, 131 Photoelectric conversion module

Claims (14)

A laminate of a photoelectrode layer, an insulating layer and a catalyst layer;
A conductive substrate;
A transparent conductive layer, and
The laminate is interposed between the conductive substrate and the transparent conductive layer,
The photoelectric conversion element, wherein the photoelectrode layer and at least one of the insulating layer and the catalyst layer are a fired body of a green sheet.   The photoelectric conversion element according to claim 1, wherein the photoelectrode layer, the insulating layer, and the catalyst layer are green sheet fired bodies.   The photoelectric conversion element according to claim 1, wherein the laminate is interposed between the conductive substrate and the transparent conductive layer such that the catalyst layer is disposed on the conductive substrate side.   The photoelectric conversion element according to claim 1, wherein the conductive substrate has flexibility. A resin base material having flexibility;
The photoelectric conversion element according to claim 1, wherein the transparent conductive layer is formed on the resin base material.   The photoelectric conversion element according to claim 1, wherein the photoelectrode layer is a porous semiconductor layer containing semiconductor fine particles, and the semiconductor fine particles are necked. A photoelectrode layer;
An insulating layer;
A catalyst layer;
A collecting electrode, and
The current collecting electrode is interposed between the photoelectrode layer and the insulating layer,
The catalyst layer is provided on one main surface of the insulating layer,
The photoelectric conversion element, wherein the photoelectrode layer and at least one of the insulating layer and the catalyst layer are a fired body of a green sheet.   A photoelectric conversion module in which a plurality of the photoelectric conversion elements according to claim 1 are electrically connected. Forming a laminate comprising a photoelectrode layer precursor, an insulating layer precursor and a catalyst layer precursor;
And firing the laminate.
The said photoelectrode layer precursor and at least one of the said insulating layer precursor and the said catalyst layer precursor are manufacturing methods of the photoelectric conversion element which consists of a green sheet. And further comprising a step of bonding the fired body of the laminate and the transparent conductive layer,
The method for producing a photoelectric conversion element according to claim 9, wherein the laminate of the fired body of the laminate and the transparent conductive layer are bonded by pressure bonding.   The manufacturing method of the photoelectric conversion element of Claim 9 further equipped with the process of bonding the said laminated body with respect to a conductive base material. Forming a photoelectrode layer precursor on one main surface of the collecting electrode;
Forming an insulating layer precursor and a catalyst layer precursor on one main surface of the conductive substrate;
The other main surface of the current collecting electrode and the insulating layer precursor are bonded to face each other, the current collecting electrode on which the photoelectrode layer precursor is formed, the insulating layer precursor and the catalyst layer precursor are Forming a laminate in which the formed conductive base material is integrated; and
And firing the laminate.
The said photoelectrode layer precursor and at least one of the said insulating layer precursor and the said catalyst layer precursor are manufacturing methods of the photoelectric conversion element which consists of a green sheet. A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
A laminate in which the catalyst layer precursor, the insulating layer precursor, and the photoelectrode layer precursor are sequentially laminated. A conductive substrate;
A catalyst layer precursor comprising a green sheet;
An insulating layer precursor comprising a green sheet;
A photoelectrode layer precursor made of a green sheet,
A photoelectrode material in which the catalyst layer precursor, the insulating layer precursor, and the photoelectrode layer precursor are sequentially laminated on one main surface of the conductive substrate.

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