JP2014239023A - Current collector for dye-sensitized solar battery, method for manufacturing material therefor, and dye-sensitized solar battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a current collector for a dye-sensitized solar battery which is superior in the capability of allowing an electrolyte to pass therethrough, and enables the achievement of a high power generation efficiency when being used for a dye-sensitized solar battery; method for manufacturing a material thereof; and dye-sensitized solar battery.SOLUTION: A current collector for a dye-sensitized solar battery comprises a porous sintered metallic thin film having a thickness of 5-60 μm and a porosity of 1-80%, and many through-holes isotropically communicating with one another. When folding the porous sintered metallic thin film while stepwise changing the diameter of a mandrel to a smaller one in a cylinder mandrel test, no crack is caused in the outer surface of a portion of the film where the film is folded until the diameter is made 6 mm.

Description

  The present invention relates to a current collector for a dye-sensitized solar cell, a method for producing the current collector, and a dye-sensitized solar cell.

  The dye-sensitized solar cell is called a wet solar cell or a Gretzel battery, and is characterized in that it has an electrochemical cell structure using an electrolytic solution without using a silicon semiconductor. For example, a porous semiconductor layer such as a titania layer formed by baking titanium dioxide powder or the like on an anode electrode using a transparent conductive film such as a transparent conductive glass plate and adsorbing a pigment to the anode, and a conductive glass plate (conductive A simple structure in which an iodine solution or the like is disposed as an electrolyte between a counter electrode (cathode electrode) made of a conductive substrate).

The power generation mechanism of the dye-sensitized solar cell is as follows.
Light incident from the transparent conductive film surface, which is the light-receiving surface, is absorbed by the dye adsorbed on the porous semiconductor layer, causing electronic excitation, and the excited electrons move to the semiconductor and are guided to the conductive glass. . Next, the electrons that have returned to the counter electrode are led to the dye that has lost the electrons through an electrolyte such as iodine, and the dye is regenerated.

  Dye-sensitized solar cells are attracting attention as low-cost solar cells because they are less expensive than silicon-based solar cells and do not require large-scale production facilities. For example, it is considered to omit an expensive transparent conductive film. In addition, since the transparent conductive film has a large electric resistance, there is also a problem that it is not suitable for increasing the size of the battery.

  One method for omitting the transparent conductive film is to provide a wiring made of a conductive metal instead of the transparent conductive film disposed on the glass surface. However, in this case, a part of the incident light is blocked by the metal wiring part, resulting in a decrease in efficiency.

  To improve this point, for example, a photoelectric conversion element in which a dye-carrying semiconductor layer is formed on a transparent substrate that does not have a transparent conductive film on the light irradiation side, and a perforated current collecting electrode is disposed on the dye-carrying semiconductor layer Is disclosed (see Patent Document 1). The perforated current collecting electrode has a network or lattice structure, and is placed on a coating film on a porous semiconductor substrate and fired at 500 ° C. for 30 minutes.

  In addition, for example, a wire mesh having a wire diameter of 1 μm to 10 mm is used as a collecting electrode having holes, a paste which is a material of the porous semiconductor layer is applied to the wire mesh, and the paste is baked to form a porous semiconductor layer. Later, a technique has been disclosed in which a wire mesh is disposed with a porous semiconductor layer facing a glass transparent substrate having no transparent conductive film (see Patent Document 2).

  However, these technologies use a wire mesh or other perforated plate that has been processed and formed in advance as a current collecting electrode, so there is a limit to reducing the thickness of the wire mesh etc. due to the size limitation of the material such as fine metal wires. is there. Therefore, due to the thick thickness of the wire mesh or the like, the diffusion resistance when the electrolyte moves to the porous semiconductor layer through the wire mesh or the like is increased, which may cause a decrease in photoelectric conversion efficiency.

  On the other hand, for example, a method of depositing a metal such as tungsten, titanium, nickel or the like as a collecting electrode by a method such as sputtering or vapor deposition and then patterning by photolithography or the like is disclosed (see Patent Document 3). ). The resulting collector electrode is a very thin metal film.

  However, in this method, the manufacturing process of the collecting electrode is complicated. Moreover, when the current collecting electrode is too thin, there is a risk that the role and performance as the current collecting electrode may be insufficient. At this time, if it is attempted to form the current collecting electrode in a moderately thick film, the film formation may take too much time and cost.

  On the other hand, it is composed of a sintered metal body obtained by sintering metal powder, and has a plurality of pore portions dispersed and arranged therein, and the porosity thereof is 10% by volume or more and 50% by volume or less. A sintered metal sheet material for an electrochemical member is disclosed in which the average pore diameter is 1 μm or more and 30 μm or less, and a part of the plurality of pores is arranged to open to the surface. (See Patent Document 4). The sintered metal sheet material for electrochemical members is obtained by sintering a raw material slurry formed into a green sheet. The thickness of the metal sheet material is, for example, about 0.03 mm to 0.3 mm.

  In view of the description in the technical field column of the specification, the above sintered metal sheet material for an electrochemical member includes an electrode plate for an electrolysis apparatus, an electrode for an electroplating apparatus, a current collector for an electric double layer capacitor, Although it is thought that it aims at improving the malfunction of the prior art in uses, such as a collector of a water electrolyte secondary battery, there is no concrete disclosure. In order to obtain a sheet material having a thickness of about 0.03 mm, a metal powder having an average particle diameter of 0.015 mm or less is used. However, when the metal powder is Ti, the surface area is large and surface oxidation is caused. Since it becomes large, insufficient sintering is likely to occur, and sufficient strength cannot be obtained. In this manufacturing method, it is actually difficult to obtain a sheet material having a thickness of about 0.03 mm which is the lower limit value. It is.

  In addition, a slurry manufacturing process for preparing a slurry made of a material containing a raw material powder, a binder, and water, in which bubbles are dispersed and formed, a green body forming process for forming a green body from the slurry, and sintering the green body A method for producing a porous sintered body having a sintering process, wherein a technique in which the green body forming process includes a predetermined archival process, a freeze-solidification process, and a vacuum freeze-drying process is disclosed (see Patent Document 5). . The slurry manufacturing process is added to the slurry by mixing the materials and adjusting the slurry, removing the bubbles and dissolved gas from the slurry, and stirring while introducing the additive gas into the slurry. It is said that the amount of gas contained in the slurry can be precisely controlled by having a bubble nucleus forming step of dispersing and forming bubble nuclei made of gas. As an example using titanium powder as a raw material, a porous sintered body having a high porosity significantly exceeding 80% and an average pore diameter of several hundred μm or more is disclosed.

  In addition, regarding the metal sintered body described above, the present inventors have disclosed a technique of using a commercially available porous titanium sheet (trade name: Typorus, made by Osaka Titanium Co., Ltd., thickness: 100 μm) as a collecting electrode of a dye-sensitized solar cell. (See Patent Document 6). This porous titanium sheet is a porous metal body in which a large number of pores communicate isotropically, and contributes to improvement in power generation efficiency.

JP 2001-283941 A JP 2007-73505 A JP 2005-158470 A JP 2011-99146 A JP 2010-229432 A WO2010 / 150461

  The problem to be solved by the present invention is that the conventional technique using a porous sintered metal sheet as a collecting electrode of a dye-sensitized solar cell contributes to further improvement in power generation efficiency, and further improvement is required. It is a point.

  The current collector for a dye-sensitized solar cell according to the present invention has a thickness of 5 μm to 60 μm, a porosity of 1% to 80%, has a number of isotropically communicating through holes, and a cylindrical mandrel In the test, when the diameter of the mandrel is gradually changed to a smaller one, it is characterized by comprising a porous sintered metal thin film that does not crack on the outer surface of the bent part up to a diameter of 6 mm.

  In the current collector for dye-sensitized solar cell according to the present invention, any one of the porous sintered metal thin films selected from Ti, W, Mo, Rh, Pt and Ta, or 1 of these may be used. It is preferable that it is a seed | species or an alloy containing 2 or more types.

  The dye-sensitized solar cell according to the present invention is disposed between a transparent substrate, a conductive substrate serving as a cathode electrode, and between or in contact with the transparent substrate between the transparent substrate and the conductive substrate. A porous semiconductor layer adsorbed with a dye, and the above-described dye-sensitized solar cell current collector that is disposed in contact with the opposite side of the porous semiconductor layer to the transparent substrate and serves as an anode electrode. It is characterized by being sealed.

Moreover, the manufacturing method of the collector material for dye-sensitized solar cells which concerns on this invention is characterized by including the process of the following (a), (b), (c) and (d).
(A) A metal composition containing a metal hydride powder or dehydrogenated metal powder, a paste-like composition containing a binder component and a solvent component is applied onto a substrate, formed into a film, and then dried to volatilize the solvent component. (B) Debinding step for removing the binder component by heating the peeled dry molded body and removing the binder component (d) Debinding process Sintering step of sintering the subsequent dried molded body at 700 ° C to 1100 ° C

  Further, in the method for producing a current collector material for a dye-sensitized solar cell according to the present invention, the metal raw material is titanium hydride powder, or a mixture of metal titanium powder and titanium hydride powder, and hydrogenation in the metal raw material is performed. The amount of titanium powder is preferably 0.1% by mass to 100% by mass.

  Moreover, it is preferable that the said base material is PET (polyethylene terephthalate) in the manufacturing method of the collector material for dye-sensitized solar cells which concerns on this invention.

  Moreover, it is preferable that the manufacturing temperature of the collector material for dye-sensitized solar cells which concerns on this invention is 150 to 450 degreeC in heating temperature in the said binder removal process.

  Moreover, it is preferable that the heating atmosphere of the said binder removal process is an oxidizing atmosphere in the manufacturing method of the collector material for dye-sensitized solar cells which concerns on this invention.

  Moreover, it is preferable that the manufacturing method of the collector material for dye-sensitized solar cells which concerns on this invention places the dry molded object on the setter of the material which does not react with a metal raw material in the said sintering process.

  Moreover, the method for producing a current collector material for a dye-sensitized solar cell according to the present invention comprises heating to a temperature at which hydrogen desorbs from titanium hydride under a pressure condition lower than atmospheric pressure in the sintering step. It is preferable to include a step of separating hydrogen contained in titanium fluoride.

  Moreover, it is preferable that the manufacturing temperature of the collector material for dye-sensitized solar cells which concerns on this invention is the heating temperature of the process of isolate | separating the hydrogen contained in titanium hydride is 400 to 600 degreeC.

  Further, the method for producing a current collector material for a dye-sensitized solar cell according to the present invention includes a transparent substrate, a conductive substrate to be a cathode electrode, and the transparent substrate between the transparent substrate and the conductive substrate. A porous semiconductor layer that is disposed close to or in contact with the dye and adsorbs a dye, and the above-described dye-sensitized solar cell that is disposed in contact with the opposite side of the porous semiconductor layer to the transparent substrate and serves as an anode A current collector using a current collector material obtained by a method for producing a current collector material is provided, and an electrolyte is sealed.

  The current collector for a dye-sensitized solar cell according to the present invention has a thickness of 5 μm to 60 μm, a porosity of 1% to 80%, has a number of isotropically communicating through holes, and a cylindrical mandrel It was used for a dye-sensitized solar cell because it consists of a porous sintered metal thin film in which cracks do not occur on the outer surface of the bent part up to a diameter of 6 mm when the diameter of the mandrel is bent instead of gradually decreasing in the test. Sometimes the electrolyte has excellent liquid permeability and high power generation efficiency can be obtained.

  Moreover, the manufacturing method of the collector material for dye-sensitized solar cells which concerns on this invention includes the metal raw material containing a hydrogenated metal powder or a dehydrogenated metal powder on a base material, a binder component, and a solvent component. After forming a film by applying a paste-like composition, drying is performed to volatilize the solvent component to obtain a dried molded body, (b) a peeling process for peeling the dried molded body from the substrate, (c The present invention includes a debinding step for heating the peeled dry molded body to remove the binder component, and (d) a sintering step for sintering the dried molded body after debinding at 700 ° C to 1100 ° C. Such a dye-sensitized solar cell current collector can be suitably and inexpensively obtained, and at this time, there is little oxidation contamination during the binder removal treatment and carbon contamination from the organic component of the binder.

FIG. 1 is a diagram showing a schematic configuration of a dye-sensitized solar cell according to the present embodiment.

  An example of an embodiment of the present invention (hereinafter referred to as this embodiment) will be described below.

First, the current collector for a dye-sensitized solar cell according to this embodiment will be described.
A collector for a dye-sensitized solar cell according to the present embodiment (hereinafter, this may be simply referred to as a collector. The collector is generally synonymous with a collector electrode) has a thickness of 5 μm to 5 μm. 60 μm and porosity of 1% to 80%, having a large number of isotropically communicating through holes, and gradually changing the diameter of the mandrel to a smaller one in the cylindrical mandrel test (cylindrical mandrel bending test) When bent, it is made of a porous sintered metal thin film that does not crack on the outer surface of the bent portion up to a diameter of 6 mm.

  Since a porous sintered metal thin film is used, compared with the case where a current collector is provided on a porous semiconductor layer or the like by a thin film forming method, etc., the current collector preparation work and thus the dye-sensitized solar cell preparation work are more complicated. Is greatly reduced.

  As described above, the thickness of the porous sintered metal thin film is 5 μm to 60 μm, preferably 5 μm to 50 μm, and more preferably 10 μm to 30 μm. When the thickness of the porous sintered metal thin film is significantly less than 5 μm, the number of particles present in the thickness direction is decreased, and the strength as a metal porous body may be impaired. On the other hand, if the thickness of the porous sintered metal thin film greatly exceeds 60 μm, when used in a dye-sensitized solar cell, the flow resistance of the electrolyte solution inside the thin film increases, and the electrolyte inside or between both surfaces of the thin film becomes large. There is a possibility that the flowability and diffusibility are deteriorated, and that the adhesion to the porous semiconductor layer and the bonding force are impaired. The thickness of the porous sintered metal thin film means the average thickness.

As described above, the porosity of the porous sintered metal thin film is 1% to 80%, preferably 30% to 60%. When the porosity of the porous sintered metal thin film is significantly lower than 1%, the flow resistance of the electrolyte solution inside the thin film increases when used in a dye-sensitized solar cell, and the electrolyte inside or between both surfaces of the thin film becomes large. The flowability and diffusibility are deteriorated, and the distribution and diffusion of the electrolyte inside the thin film are insufficient, which may impair the uniform penetration of the electrolyte into the porous semiconductor layer. On the other hand, if the porosity of the porous sintered metal thin film greatly exceeds 80%, the adhesion and bonding strength with the porous semiconductor layer may be impaired. Moreover, there exists a possibility that the intensity | strength as a metal porous body may be impaired. Moreover, there exists a possibility that electroconductivity suitable as an electrode may not be obtained. In addition, it goes without saying that the definition of terms is obvious, but the unit of porosity is volume%.
The porosity is measured by the same method as the porosity of the dye-sensitized solar cell current collector material described later.

  In the porous sintered metal thin film, when the diameter of a mandrel (mandrel: core rod) is changed to a gradually smaller one in a cylindrical mandrel test and bent, the outer surface of the bent portion does not crack up to a diameter of 6 mm. That is, the diameter of 6 mm means the minimum diameter of the mandrel under the condition that no cracks occur when the porous sintered metal thin film is bent.

  The cylindrical mandrel test is performed by the method defined in JIS-K5600-5-1. If the bending is repeated while the diameter of the mandrel is gradually reduced, cracks are generated on the outer surface of the porous sintered metal thin film as the bending rate increases. Therefore, the cylindrical mandrel test can be said to be a test for determining the flexibility or a kind of strength of the porous sintered metal thin film. In the cylindrical mandrel test, it is preferable that the outer surface does not crack until the diameter of the mandrel is 4 mm. When a crack occurs under the condition that the mandrel diameter greatly exceeds 6 mm, the durability as an electrode may be lowered when used in a dye-sensitized solar cell.

  The porous sintered metal thin film has an average pore diameter of preferably 5 μm to 25 μm, and more preferably 5 μm to 15 μm. When the average pore diameter of the porous sintered metal thin film is much less than 5 μm, the flow resistance of the electrolyte solution inside the thin film increases when used in a dye-sensitized solar cell, and the electrolyte inside or between both surfaces of the thin film As a result, the flowability and diffusibility of the electrolyte deteriorate, and the distribution / diffusion of the electrolyte inside the conductive metal layer becomes insufficient, which may impair the uniform penetration of the electrolyte into the porous semiconductor layer. On the other hand, if the average pore diameter of the porous sintered metal thin film greatly exceeds 25 μm, the strength of the metal porous body may be impaired. In addition, when the average pore diameter is excessively large, the area of the non-voided portion is also increased, so that the uniform flow of the electrolyte inside the thin film and the uniform diffusion of the electrolyte from the thin film opening to the porous semiconductor layer are hindered. There is a risk.

The average pore diameter is a value when measured by a mercury intrusion method. Using a mercury intrusion type pore distribution measuring device (Pascal I 140 and Pascal 440 manufactured by CARLOERBA INSTRUMENTS, measurable range: specific surface area 0.1 m ² / g or more, pore distribution 0.0034 to 400 μm), pressure range 0. In the range of 3 kPa to 400 kPa, and 0.1 MPa to 400 MPa, the press-fitted volume is calculated as a side area according to the cylindrical pore model, integrated and measured.

  As described above, the porous sintered metal thin film has a large number of through-holes communicating in an isotropic manner. Here, “isotropically communicating” means not only that a large number of pores communicate with each other only in the direction of the thickness of the porous sintered metal, that is, so as to have anisotropy, so that the through-holes are formed. The term “communication” means to communicate in a direction along the plane of the bonded metal so that it is isotropic in all directions in three dimensions. Thereby, when used in a dye-sensitized solar cell, the electrolyte penetrates more uniformly in the thin film, and the electrolyte diffuses more uniformly from the opening of the thin film into the porous semiconductor layer.

  As the porous sintered metal thin film, for example, a so-called foam metal using a slurry foaming method such as the technique of Patent Document 5 described above or a technique equivalent thereto can be used. However, in the case of a non-foamed metal, that is, a slurry formed without using a slurry foaming method, such as the method for producing a current collector material for a dye-sensitized solar cell according to this embodiment to be described later, A porous sintered metal thin film having a more preferable range of porosity and average pore diameter can be obtained, which is more preferable.

  When a current collector made of a porous sintered metal thin film is used as a current collecting electrode in contact with the porous semiconductor layer for a dye-sensitized solar cell, the contact area with the porous semiconductor layer, which is an aggregate of particles, is large, In addition, the particles on the surface of the porous semiconductor layer engage with the pores on the surface of the thin film in a so-called meshed state. Thereby, the bonding force between the thin film and the porous semiconductor layer is large. On the other hand, when the conductive metal layer formed by the conventional thin film forming method is used as the current collector, the openings of the through holes are discretely arranged in the direction along the plane of the conductive metal layer, and Because the number of openings is often limited or the conductive metal layer is formed in a smooth sheet, it is difficult to obtain a large bonding force between the conductive metal layer and the porous semiconductor layer. There is. This problem is more noticeable when a wire mesh is used as a current collector or when a through hole is formed in a thin plate by processing. If the bonding force between the current collector and the porous semiconductor layer is small, cracks may be generated in the electrical bonding step by heating at, for example, about 500 ° C., and the current collector and the porous semiconductor layer may be separated.

The porous sintered metal thin film is a dye-sensitized solar cell in which the metal species is any one selected from Ti, W, Mo, Rh, Pt and Ta, or an alloy containing one or more of these. When it is used, it is preferable for obtaining high corrosion resistance to the electrolyte and obtaining high conductivity. The porous sintered metal thin film preferably has an electric conductivity of 0.5 × 10 ³ Ω ⁻¹ · m ⁻¹ or more. Electrical conductivity can be measured by a four-probe method.

  In the porous sintered metal thin film, the metal raw material preferably contains a hydrogenated metal powder or a dehydrogenated metal powder, and particularly preferably, the metal raw material is a titanium hydride powder, a dehydrogenated metal powder or a metal titanium powder, and titanium hydride. It is a powder mixture, and the amount of titanium hydride powder in the metal raw material is preferably 0.1% by mass to 100% by mass. More preferably, it is 0.1 to 30%, more preferably 0.1 to 10% from the viewpoint of ease of dehydrogenation in the dehydrogenation step described later.

  Here, as the metal titanium powder, titanium powder produced by a hydrodehydrogenation method (hereinafter referred to as “dehydrogenated titanium powder”), sponge metal powder, gas atomized metal powder, and the like can be applied. Dehydrogenated titanium powder is preferred.

  When a porous sintered metal thin film is used as a current collector, a glass fiber molded body, an inorganic porous body such as a porous alumina plate, an organic porous body such as a heat-resistant porous plastic, a metallic porous body, etc. It may be provided as an auxiliary substrate.

  The method for producing the porous sintered metal thin film is not particularly limited, and a known appropriate method can be adopted. However, the current collector for dye-sensitized solar cell according to the present embodiment described below is used. It is preferable to use a material manufacturing method.

  Since the current collector for a dye-sensitized solar cell according to the present embodiment described above is excellent in liquid permeability of an electrolyte when using a dye-sensitized solar cell, high power generation efficiency can be obtained. Further, the current collector for a dye-sensitized solar cell according to the present embodiment has excellent bending resistance and therefore has excellent durability. In addition, since the dye-sensitized solar cell current collector according to the present embodiment is flexible and lightweight, the dye-sensitized solar cell using the current collector can be made flexible and lightweight. .

Next, the manufacturing method of the collector material for dye-sensitized solar cells according to this embodiment will be described.
The manufacturing method of the collector material for dye-sensitized solar cells according to the present embodiment has a thickness of 5 μm to 60 μm and a porosity of 1% to 80%, and has a large number of isotropically communicating through holes. In this embodiment, the cylindrical mandrel test is made of a porous sintered metal thin film that does not crack on the outer surface of the bent part up to a diameter of 6 mm when the mandrel diameter is gradually changed to a smaller one. The current collector material for a dye-sensitized solar cell according to the embodiment can be suitably obtained.

The manufacturing method of the collector material for dye-sensitized solar cells according to this embodiment includes the following steps (a), (b), (c) and (d).
(A) A metal composition containing a metal hydride powder or dehydrogenated metal powder, a paste-like composition containing a binder component and a solvent component is applied onto a substrate, formed into a film, and then dried to volatilize the solvent component. (B) Debinding step for removing the binder component by heating the peeled dry molded body and removing the binder component (d) Debinding process Sintering step of sintering the subsequent dried molded body at 700 ° C. to 1100 ° C.

  The paste-like composition includes a metal raw material including a metal hydride powder or a dehydrogenated metal powder, a binder component, and a solvent component.

The metal species in the hydrogenated metal powder or dehydrogenated metal powder is any one selected from Ti, W, Mo, Rh, Pt and Ta, or an alloy containing one or more of these, When used in a sensitized solar cell, it is preferable for obtaining high corrosion resistance to the electrolyte and obtaining high conductivity. The metal species is particularly preferably Ti, specifically, titanium hydride powder (TiH ₂ powder) or dehydrogenated titanium powder.
The metal hydride powder is preferably a fine powder having a maximum particle size of 10 μm or less and an average particle size of 4 to 7 μm.

The titanium hydride powder (TiH ₂ powder) is produced by hydrogenating titanium to form a brittle titanium hydride and mechanically pulverizing it. The titanium hydride powder is suitable for the production of a thin porous titanium thin film because it is easy to obtain a fine powder as compared with the titanium metal powder. In addition, by using titanium hydride powder, a porous titanium thin film that has high toughness and high flexibility, in other words, that does not break even when bent by 180 ° can be obtained. Furthermore, titanium hydride powder has higher sinterability than metal titanium powder and can lower the sintering temperature than metal titanium powder, so that the load (severity) on the equipment in the sintering process can be kept low. It becomes possible.

  When titanium is used as the metal hydride powder of the metal raw material, use a titanium hydride powder or a mixed powder of metal titanium powder and titanium hydride powder to adjust the porosity and film thickness of the porous titanium thin film. Is preferred. In this case, the metal titanium powder is preferably a fine powder having a maximum particle size of 20 μm or less and an average particle size of 10 μm to 15 μm. The mixing ratio of the titanium metal powder and the titanium hydride powder can be arbitrarily set, but the amount of the titanium hydride powder in the metal raw material is preferably 0.1% by mass to 100% by mass. More preferably, it is 0.1 to 30%, more preferably 0.1 to 10% from the viewpoint of ease of dehydrogenation in the dehydrogenation step described later. The titanium hydride powder has higher sinterability than the metal titanium powder, and the porosity of the resulting porous titanium thin film varies depending on the mixing ratio. The optimum mixing ratio is selected depending on the porosity to be obtained. Furthermore, the titanium porous body thin film with high toughness can be obtained by setting it as this range. The metal titanium powder is preferably dehydrogenated titanium powder.

  The metal raw material contains metal elements such as titanium, aluminum, vanadium, niobium, zirconium, tantalum, molybdenum and iron in addition to the metal hydride powder, and preferably contains an alloy powder of these metals. As such alloy powder, specifically, Ti-6 mass% Al-4 mass% V powder, Ti-6 mass% Al-7 mass% Nb powder, Ti-6 mass% Al-2 mass% Nb- 1 mass% Ta powder, Ti-15 mass% Zr-4 mass% Nb-4 mass% Ta powder, Ti-3 mass% Al-2.5 mass% V powder, Ti-13 mass% Nb-13 mass% Zr A powder, Ti-15 mass% Mo-5 mass% Zr-3 mass% Al powder, Ti-12 mass% Mo-6 mass% Zr-2 mass% Fe powder, Ti-15 mass% Mo powder, etc. are mentioned.

  In addition, said maximum particle size and average particle diameter are calculated | required with the laser diffraction type particle size distribution measuring apparatus (LA-300 by the Beckman Coulter company).

  As the binder component, methyl cellulose, polyvinyl alcohol, ethyl cellulose, acrylic, polyvinyl butyral, and the like can be used. As the solvent component, water, ethanol, toluene, isopropanol, terpineol, butyl carbitol, cyclohexane, methyl ethyl ketone, or the like can be used. Moreover, you may add plasticizers, such as glycerol and ethylene glycol, surfactants, such as an alkylbenzenesulfonate, and foaming agents, such as ammonium hydrogencarbonate, to a paste-like composition as needed.

  The metal raw material, the binder component and the solvent component are mixed to obtain a paste-like composition. A known method can be used for mixing the metal raw material, the binder component, and the solvent component. For example, a mixer with a stirrer, a rotary mixer, a three-roll mill, or the like can be used as appropriate. The mixing may be performed simultaneously with pulverization, and a pulverizing mixer such as a vibration mill and a ball mill can also be used.

  The porosity of the porous titanium thin film can be adjusted by the particle size of the titanium raw material, the type of the titanium raw material, the components and addition amount of a binder and a foaming agent, and the sintering temperature described later.

  The paste-like composition is applied onto a substrate to form a film, and then the solvent is evaporated to produce a film-like dry molded body. The paste-like composition is applied and formed into a film with a thickness of 20 μm to 80 μm, for example.

  If a base material is a material which can be peeled with a dry molded object in a peeling process, there will be no restriction | limiting. For example, polyesters such as PET (polyethylene terephthalate) and PEN (polyethylene naphthalate), polyvinyls such as polyethylene, polypropylene, polystyrene, and polyvinyl alcohol, metal foils, ceramic plates, and the like can be given, but inexpensive PET is preferable.

  Coating / film formation methods include a method in which a viscous composition such as a doctor blade method is directly applied onto a substrate to form a film, and a viscosity composition such as a lip coating method is applied while being extruded onto a substrate. Any of a film forming method, a method of transfer coating a viscous composition such as offset printing, and gravure printing to form a film may be used. For example, riad coater coater, blade coater, rod coater, knife coater, squeeze coater, impregnation coater, reverse roll coater, transfer roll coater, gravure coater, kiss roll coater, slot die coater, cast coater, spray coater, curtain coater, A calendar coater, an extrusion coater, a bar coater or the like can be used. Among these, the doctor blade method that can continuously perform film formation and drying is preferable.

  The thickness of the molded body after film formation can be adjusted by the particle size of the solid component contained in the paste. By using titanium hydride powder having a maximum particle size of 10 μm or metal titanium powder having a maximum particle size of 20 μm as a paste raw material as in the present invention, a thin film of 20 μm can be produced. Of course, even if a paste containing a fine titanium raw material is used, it is possible to manufacture a slightly thick film having a thickness of 50 μm or 60 μm by adjusting the clearance of the doctor blade.

  The solvent component is volatilized from the molded body after film formation to obtain a dried molded body. The drying process can be performed under normal pressure, reduced pressure, or pressurized conditions, but if the solvent evaporates too quickly, cracks will form in the dried molded product, so the temperature, pressure, and air volume should be adjusted so that cracks do not occur. Choose. The temperature is preferably 80 ° C. to 160 ° C., and the pressure is preferably atmospheric pressure. Giving a weak air flow is also effective for increasing the drying efficiency. In addition, when drying under pressure, it will serve also as the press processing of the pre-sintering molded object demonstrated below.

  The dried molded body may be further pressed. Since the contact area between the metal powders increases due to the press treatment, the number of necking sites increases. Moreover, the higher the pressure of the press treatment, the higher the electrical conductivity, the lower the film thickness, and the lower the porosity. Therefore, it is necessary to select a pressure condition according to the application. However, if the pressing pressure is too low, the contact area between the metal powders does not increase, and if it is too high, the porosity falls outside an appropriate range, or the metal powder undergoes plastic deformation. Therefore, a preferable press pressure range is 0.1 MPa to 100 MPa. Moreover, it is preferable to use a suitable cushion material in a press process. As the cushioning material, an appropriate material such as paper, metal foil, silicon, heat resistant plastic, rubber or the like can be used. The pressing method can be performed by an appropriate method such as a flat plate press, a roll press, or a vacuum laminator.

  In order to peel the base material from the obtained dry molded body, an appropriate method can be adopted as long as the dry molded body is not damaged or deformed. For example, compressed air is blown between the base material and the dry molded body or By inserting a sharp knife-like material, there is a method in which the substrate is partially peeled from the dried molded body, the peeled portion is mechanically pinched and the entire substrate is pulled apart.

  If the binder is heated without peeling off the base material, the base material and the dry molded body are fused, the base material is thermally deformed, or the dry molded body is deformed or damaged due to a difference in thermal expansion between the base material and the dry molded body. Etc. are not preferable.

  The peeled dried molded body is preferably placed on a setter (shelf plate) made of a material that does not react with Ti in the next debinding step and sintering step.

Examples of the setter include BN, ZrO ₂ , and Al ₂ O ₃ . Although not included in this embodiment, these powders may be placed between a setter such as molybdenum or stainless steel and a dry molded body. By laying the powder, the movement of the material accompanying the shrinkage of the dry molded body during sintering becomes easy, which is effective for preventing cracks in the dry molded body during sintering.

The dried molded body placed on the setter is heated at a temperature lower than the sintering temperature before sintering to decompose the binder component, solvent, binder, plasticizer, and other impurities in the dried molded body. And removed by evaporation or combustion (debinding step). The heating is preferably performed under a pressure condition lower than atmospheric pressure. Further, the heating is preferably performed under a gas atmosphere condition of either an inert gas atmosphere or an oxidizing gas atmosphere. Examples of the gas used in the inert gas atmosphere include argon and helium. In the case of an inert gas atmosphere, it may be under a pressure condition higher than atmospheric pressure or under a pressure condition lower than atmospheric pressure, or may be in a state with a gas flow rate. Thereby, the collector material for dye-sensitized solar cells with high toughness can be obtained without being oxidized. The gas used in the oxidizing gas atmosphere is a gas containing 1% or more of oxygen atoms. Specific examples thereof include air, oxygen, oxygen-enriched air, and a mixed gas of oxygen gas and inert gas. In the case of heating in an oxidizing atmosphere, a titanium porous thin film having a low carbon content can be obtained, and treatment in an air atmosphere is preferred because of its low cost.
In the binder removal step, plasma treatment and ozone treatment may be used in combination.

  Although the heating conditions at the time of debinding vary depending on the binder component to be used, it is preferable to hold at 150 to 450 ° C. for 0.1 to 6 hours depending on the volatilization conditions of the component.

The lower the pressure at the time of binder removal, the better the decomposition / evaporation of the organic component is preferred. From this viewpoint, 10 ⁻² mbar or less is particularly preferred. However, when the organic substance is decomposed and evaporated by heating, the inside of the vacuum furnace is contaminated with the evaporated organic substance. From the viewpoint of preventing this, it is preferable to remove the binder at a pressure higher than 10 ⁻² mbar, for example, ¹ mbar to 10 ⁻¹ mbar. In this case, it is preferable to perform heat treatment while introducing a small amount of an inert gas such as argon into the furnace under reduced pressure.

The binder removal is preferably performed using, for example, a vacuum sintering furnace having a dewaxing function (for example, a horizontal vacuum sintering furnace VHSG 30/30/60 manufactured by Shimadzu Mektem Co., Ltd.). In a vacuum sintering furnace having a dewaxing function, Ar gas is introduced into the furnace under a pressure of ¹ mbar to 10 ⁻¹ mbar in the furnace, whereby the evaporated organic component is transferred to the condenser along the Ar gas flow. It becomes possible to guide. The use of a vacuum sintering furnace with a dewaxing function not only allows the titanium dry compact to be oxidized and does not contaminate the furnace, but also removes the binder from the sintering process. There is an advantage that it can be done in a furnace.

  In the sintering step, the dried molded body after debinding is sintered at 700 ° C to 1100 ° C. In the sintering step, it is preferable that hydrogen gas is removed from the unsintered dry molded body by dehydrogenation reaction from titanium hydride before the dry molded body is sintered (main firing process) (dehydrogenation process). ). The dehydrogenation step may be omitted when the ratio of titanium hydride powder in the mixture of titanium metal powder and titanium hydride powder is 10% or less by mass ratio.

In the dehydrogenation step, the treatment is preferably performed at a temperature of 400 ° C. to 600 ° C. until the generation of hydrogen desorbed (separated) from the dried molded body after the binder removal step is completely eliminated. In this case, the time required for dehydrogenation is appropriately selected according to conditions such as the ultimate pressure of the vacuum pump, the displacement, the volume of titanium hydride, and the like, but is, for example, about 0.5 to 96 hours. At this time, in order to efficiently exhaust the generated hydrogen, the treatment may be performed under an inert gas stream such as argon, or may be performed under a pressure of 10 ⁻¹ mbar or less. In the latter case, the pressure is more preferably 10 ⁻³ mbar or less.

  In this baking process, it adjusts suitably with the porosity and thickness of a porous titanium thin film with the sintering temperature and the temperature increase rate. The sintering temperature is selected in the range of 700 ° C. to 1100 ° C. and held for 0.1 to 6 hours. The rate of temperature rise is set so that the material shrinkage does not catch up with the temperature rise and partial non-uniform shrinkage occurs, leading to cracks in the material. For example, the heating rate is preferably 5 ° C./min or less. In addition, if it is 2 degrees C / min or less, it will take time for temperature rising and it is not economical.

These series of steps may be continuously performed as one process with the same equipment.
By the method for producing a dye-sensitized solar cell current collector material according to this embodiment, a tough and highly flexible dye-sensitized solar cell current collector material can be obtained. This is because fine hydrogenated metal hydride powder is used as a raw material, and the dehydrogenation step and the main firing step are performed in a series of steps. It is considered that pure titanium having a high surface is formed, and this is directly exposed to the atmosphere to oxidize the surface without being oxidized by the main firing step.

  By appropriately selecting the kind of metal raw material and the sintering temperature in the main firing step, a current-collecting material for a dye-sensitized solar cell having a desired porosity can be obtained by a single sintering. In addition, the porosity of the collector material for dye-sensitized solar cells can be controlled by increasing / decreasing the amount of the binder component or increasing / decreasing the amount of the foaming agent added.

  By the method for producing a current collector material for dye-sensitized solar cells according to the present embodiment, the dye-sensitized solar with high porosity and high toughness with a porosity of 1% to 80% and a thickness of 60 μm or less. A battery current collector material can be obtained.

In addition, the porosity of the collector material for dye-sensitized solar cells is the volume (A), mass (W), true density (calculated from the thickness, area of the collector material for dye-sensitized solar cells) ρ) is calculated by the following formula. The thickness is measured using a micrometer.
Porosity (%) = (1−W / Aρ) × 100 = (A−W / ρ) / A × 100

This firing step is performed in a substantially sealed container, and the standard free energy values of carbides and oxides in the vicinity of the green body before sintering are larger than the sintered metal powder in the sintering temperature range. It is preferable to perform by arranging a metal having the following (hereinafter referred to as getter material).
The substantially sealed container is, for example, a vacuum baking furnace whose opening is closed by a door.

  Sintering in a container with a getter material prevents oxygen from being mixed outside the container, and oxygen in the container is preferentially reacted and consumed by the getter material, so that oxidation of the sintered body is suppressed More preferable. The material of the getter material varies depending on the type of metal to be sintered. For example, when the metal powder is titanium, the getter material is preferably Ti, Zr or Hf.

  According to the manufacturing method of the current collector material for dye-sensitized solar cell according to the present embodiment described above, the material of the current collector for dye-sensitized solar cell according to the present embodiment, in other words, porous A sintered metal thin film can be suitably obtained.

Next, a dye-sensitized solar cell 10 according to this embodiment will be described with reference to FIG.
A dye-sensitized solar cell 10 according to this embodiment schematically shown in FIG. 1 is transparent between a transparent substrate 12, a conductive substrate 14 serving as a cathode electrode, and between the transparent substrate 12 and the conductive substrate 14. A porous semiconductor layer 16 that is disposed in proximity to or in contact with the substrate 12 and adsorbs a dye, and a dye-sensitized sun that is disposed in contact with the opposite side of the porous semiconductor layer 16 to the transparent substrate 12 and serves as an anode. A battery current collector 18 is provided, and an electrolyte 20 is sealed. The dye-sensitized solar cell current collector 18 is a dye-sensitized solar cell current collector according to the present embodiment, or a dye-sensitized solar cell current collector material according to the present embodiment. A current collector for a dye-sensitized solar cell using a material obtained by the method. In FIG. 1, reference numeral 22 denotes a sealing material.

  The constituent elements of the dye-sensitized solar cell 10 other than the current collector 18 for the dye-sensitized solar cell can be produced by an appropriate method using an appropriate material that is usually employed.

The transparent substrate 12 may be, for example, a glass plate or a plastic plate, but using a plastic plate is preferable because flexibility can be imparted to the dye-sensitized solar cell. When using a plastic plate, for example, PET, PEN, polyimide, cured acrylic resin, cured epoxy resin, cured silicone resin, various engineering plastics, cyclic polymers obtained by metathesis polymerization, and the like can be mentioned. Further, on the transparent substrate 12, a transparent conductive film such as ITO (indium oxide film doped with tin), FTO (tin oxide film doped with fluorine), SnO ₂ film, Ti, W, Mo, Rh, You may provide fine metal wires, such as Pt and Ta.

The conductive substrate 14 is the same substrate as the transparent substrate 12, and is formed on a part of the surface of the substrate facing the electrolyte 20, for example, ITO, FTO, SnO ₂ film, Ti, W, Mo, Rh, Pt, Ta A conductive film such as a metal film is laminated, and a catalyst such as platinum, conductive polymer (polyaniline, polypyrrole, polythiophene, etc.), carbon material (graphite, carbon black, graphene, carbon nanotube, etc.) is further formed on the conductive film. A membrane is provided. Further, the transparent substrate may be omitted and the catalyst film may be provided on the metal foil. Examples of the metal foil include Fe, SUS, Ti, and Cu, and Ti is preferable.

The porous semiconductor layer 16 can be made of any suitable material such as ZnO or SnO _2, but TiO ₂ is preferred. The shape of fine particles such as TiO ₂ is not particularly limited, but is preferably about 1 nm to 100 nm.
The porous semiconductor layer 16 is preferably formed into a desired thick film by repeating a firing operation at a temperature of, for example, 300 ° C. to 550 ° C. after forming a thin film of TiO ₂ paste.
A dye is adsorbed on the surface of the fine particles constituting the porous semiconductor layer 16. The dye has absorption in at least part of the wavelength region of 400 nm to 1000 nm, and examples thereof include metal complexes such as ruthenium dye and phthalocyanine dye, and organic dyes such as cyanine dye. The adsorption method is not particularly limited, and for example, a so-called impregnation method in which a dye-sensitized solar cell current collector 18 in which a porous semiconductor layer 16 is formed in a dye solution is immersed and the dye is chemically adsorbed on the fine particle surface can be used. .

  The transparent substrate 12 and the porous semiconductor layer 16 may or may not be in contact with each other, but the distance between the two is preferably as short as possible. Since the dye-sensitized solar cell 18 and the conductive substrate (counter electrode) 14 are arranged so as not to contact each other, for example, the dye-sensitized solar cell 18 is sufficiently resistant to the electrolyte 20 and does not hinder the diffusion of the electrolyte ions. There is also a method of insulating with a spacer such as glass paper having holes. The distance between the dye-sensitized solar cell current collector 18 and the conductive substrate 14 is preferably 100 μm or less.

  The electrolyte 20 is not particularly limited, but includes, for example, iodine, lithium ions, ionic liquid, t-butylpyridine, and the like. In the case of iodine, an oxidation-reduction body composed of a combination of iodide ions and iodine is used. Can do. Further, a metal complex such as cobalt may be used as the redox pair. Moreover, it contains a solvent capable of dissolving this redox substance, and examples thereof include acetonitrile, γ-butyrolactone, propionitrile, ethylene carbonate, and ionic liquid.

  The method for injecting the electrolyte 20 is not particularly limited, and for example, a part of the sealing material 22 may be left as an opening, and the electrolyte 20 may be injected from the opening to seal the opening. Alternatively, an opening may be provided in advance in a part of the conductive substrate 14, and the opening may be sealed after injecting the electrolyte 20 therefrom.

  The sealing material 22 for sealing by injecting the electrolyte 20 between the transparent substrate 12 and the conductive substrate 14 is a thermoplastic resin sheet having a thickness of 100 μm or less after curing, a photocurable resin, a thermosetting resin. Etc. can be used.

  In the dye-sensitized solar cell 10 according to the present embodiment described above, the current collector 18 for the dye-sensitized solar cell is excellent in liquid permeability of the electrolyte 20 and high power generation efficiency can be obtained.

  In addition, the dye-sensitized solar cell other than the dye-sensitized solar cell according to the present embodiment described above, for example, the dye-sensitized solar cell according to the present embodiment is provided on a transparent substrate provided with a transparent conductive film. Dyes such as those provided with current collectors, or those in which one or more current collectors are arranged at a different site from those arranged on the opposite side of the porous semiconductor layer from the transparent substrate Needless to say, the dye-sensitized solar cell current collector according to the present embodiment can be used as appropriate for the entire sensitized solar cell.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to this Example.

First, measurement methods of various characteristics used in the examples will be described together.
(Maximum particle size, average particle size measurement method)
For the maximum particle size and average particle size (50% particle size in the integrated particle size distribution), use a laser diffraction particle size distribution analyzer (LA-300 manufactured by Beckman Coulter, Inc.) and put the measurement sample into the flow cell. And measured.
(Thickness measurement method)
The thickness of the obtained porous titanium thin film (rectangular shape) was measured at three places at equal intervals in three directions, for a total of nine places, and the average value was obtained. The three directions are the central portion, the upper side portion, and the lower side portion of the porous titanium thin film.
(Measurement method of porosity)
The volume (A) calculated from the thickness and the size of the porous titanium thin film (rectangle), the mass (W) of the measurement sample, and the true density (4.506 g / cm ³ ) of titanium were calculated by the following formula.
Porosity (%) = (A−W / 4.506) / A × 100
The size of the measurement sample was determined by measuring with a caliper.
(Evaluation of porous titanium thin film)
<Evaluation of mandrel test>
The obtained porous titanium thin film was evaluated by a mandrel test (cylindrical mandrel method). The test was conducted according to JIS K5600-5-1. The diameter of the mandrel was changed and the minimum diameter of the mandrel without cracks was determined. The presence or absence of occurrence of cracks was confirmed visually.
<Analysis of oxygen content and carbon content>
Titanium hydride powder, titanium powder, the oxygen content of the porous titanium, a carbon content, inert gas melting, respectively - infrared absorption method, combustion - was measured by an infrared absorption method.

Example 1
Polyvinyl butyral and isopropyl alcohol are mixed with TiH ₂ powder having a maximum particle size of 8 μm, an average particle size of 5 μm, an oxygen content of 0.22%, and a carbon content of 0.004%, so that the viscosity becomes 1200 mPa · S. The paste-like composition was prepared by adjusting. The pasty composition was blended so that the concentration of TiH ₂ was 60 wt%. This pasty composition was coated on a PET sheet with a slot die head type coating machine to produce a molded body. At this time, the paste discharge amount and the running speed of the PET were adjusted so that the thickness of the molded body was 30 μm. Further, the molded body was dried at 150 ° C., and isopropyl alcohol contained in the molded body was completely removed to obtain a dried molded body.

The dried molded body was cut into 300 mm × 300 mm, and the dried molded body was peeled from the PET sheet. The dry molded body was peeled from the PET by picking one end of the dry molded body and inserting a knife between the dry molded body and the base material. The dried molded article peeled from the PET sheet was set on a BN plate and set in an atmospheric furnace. The temperature was raised to 300 ° C. at a rate of 3 ° C./min and held at 300 ° C. for 2 hours (debinding step). Thereafter, the titanium compact was taken out from the atmospheric furnace and set in a vacuum sintering furnace. The inside of the furnace was evacuated and heated up to 400 ° C. under a high vacuum of 1 × 10 ⁻⁴ mbar or less. Further, the vacuum evacuation system was switched to the oil diffusion pump system and heated to a firing temperature of 800 ° C. at a temperature increase rate of 3 ° C./min while maintaining a vacuum degree of 1 × 10 ⁻⁴ mbar and held for 1 hour. After completion of the holding at 800 ° C., the furnace was cooled and sufficiently cooled, and then the material was taken out (main firing step).

  The porosity and thickness of the porous titanium thin film taken out after cooling were measured. The oxygen content was 0.02% higher than the powder, but the carbon content was unchanged from the powder. As a result of the mandrel test, no crack was observed up to a core rod diameter of 2 mm. Table 1 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the obtained porous titanium (A-1).

  The produced porous titanium (A-1) was cut into a size of 10 mm × 25 mm. A titania paste (trade name Nanoxide D, manufactured by Solaronics) was printed in the range of 5 mm × 20 mm of the cut porous titanium, dried, and baked in air at 425 ° C. for 30 minutes. On the titania after firing, the operation of further printing and firing titania base was repeated a total of 3 times to obtain a porous titanium substrate with a titania layer.

  The prepared porous Ti sheet substrate with a titania layer was impregnated with a mixed solvent solution of N719 dye (manufactured by Solaronics) in acetonitrile and t-butyl alcohol for 64 hours, and the dye was adsorbed on the titania surface. The adsorbed substrate was washed with a mixed solvent of acetonitrile and t-butyl alcohol to obtain a porous titanium substrate with a dye-adsorbed titania layer.

  Titanium foil having a size of 20 mm × 25 mm and a thickness of 20 μm was laminated on the end portion 2 mm of the surface of the porous Ti sheet substrate with the dye-adsorbing titania layer on which no titania paste was formed to obtain an anode electrode with a takeout electrode.

  On one side of a 10 mm × 25 mm titanium foil having a thickness of 50 μm, platinum was deposited by 400 nm to obtain a Ti substrate with a Pt catalyst layer. Further, a 20 mm × 25 mm titanium foil having a thickness of 20 μm was laminated on the end 2 mm of the Pt-free surface of the Ti substrate with the Pt catalyst layer to obtain a cathode electrode with a takeout electrode.

30 mm x 40 mm, 60 μm thick PEN film bonded with a resin sheet (product name: MELTONIX 1170-60, manufactured by SOLARONIX) The above resin sheet surface and the cathode electrode titanium foil with the take-out electrode Lamination was done so that the faces would face each other. Further, glass paper having a size of 12 mm × 27 mm, a thickness of 50 μm, and a porosity of 85% or more was laminated on the surface of the Pt catalyst layer of the counter electrode with the extraction electrode. Furthermore, it laminated | stacked so that the titania paste non-film-forming surface of the said anode electrode with a taking-out electrode might face glass paper. Further, the PEN film having a thickness of 30 mm × 40 mm and a thickness of 125 μm obtained by laminating the resin sheet having a thickness of 30 mm × 40 mm and a thickness of 60 μm was laminated so that the surface of the dye adsorption titania layer of the anode electrode with the extraction electrode faces each other. . In addition, an electrolyte solution insertion hole of φ3 mm was provided in the PEN film on the cathode electrode side. These were roll-pressed at a temperature of 130 ° C.
Furthermore, after the electrolyte solution of γ-butyrolactone solvent containing iodine and LiI was injected under reduced pressure from the electrolyte solution insertion hole, the electrolyte solution insertion hole was sealed with a UV curable resin, and the dye-sensitized solar cell (C-1) Got.

The photoelectric conversion performance of the obtained dye-sensitized solar cell was examined by measuring an IV curve when pseudo-sunlight having an intensity of 100 mW / cm ² was irradiated from the anode electrode side. The obtained results are shown in Table 2.

(Example 2)
When coating a PET sheet with the same equipment as in Example 1 using the slurry composition, except adjusting the discharge amount of the paste and the traveling speed of the PET so that the dry molded body thickness is adjusted to 60 μm. In the same procedure as in Example 1, peeling, debinding step in an atmospheric furnace, and main firing step in a vacuum sintering furnace were performed.

Table 1 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the porous titanium thin film (A-2) taken out after cooling.
A dye-sensitized solar cell (C-2) was obtained in the same manner as in Example 1. The results are shown in Table 2.

Example 3
In the main firing step in the vacuum sintering furnace, exfoliation and debinding in an atmospheric furnace were performed in the same manner as in Example 1 except that the firing temperature was set to 700 ° C.
Table 1 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the porous titanium thin film (A-3) taken out after cooling.
A dye-sensitized solar cell (C-3) was obtained in the same manner as Example 1. The results are shown in Table 2.

Example 4
A porous titanium thin film (paste coating, peeling, debinding process, and main firing process were performed in the same procedure as in Example 2 except that a paste-like composition blended so that the TiH ₂ concentration was 50 wt% was used. A-4) was obtained. Table 1 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the obtained porous titanium thin film.
In the same manner as in Example 1, a dye-sensitized solar cell (C-4) was obtained. The results are shown in Table 2.

(Comparative Example 1)
A porous titanium thin film (B-1) was obtained in the same manner as in Example 2 except that the debinding step was not performed and the main baking step was performed at 900 ° C. Table 3 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the obtained porous titanium thin film.
In the same manner as in Example 1, a dye-sensitized solar cell (D-1) was obtained. The results are shown in Table 4.

(Comparative Example 2)
A porous titanium thin film (paste coating, peeling, debinding process, and main firing process were performed in the same procedure as Comparative Example 1 except that a paste-like composition blended so that the TiH ₂ concentration was 50 wt% was used. B-2) was obtained. Table 3 shows the porosity, thickness, mandrel test results, oxygen content, and carbon content of the obtained porous titanium thin film.
In the same manner as in Example 1, a dye-sensitized solar cell (D-2) was obtained. The results are shown in Table 4.

DESCRIPTION OF SYMBOLS 10 Dye-sensitized solar cell 12 Transparent substrate 14 Conductive substrate 16 Porous semiconductor layer 18 Current collector for dye-sensitized solar cell 20 Electrolyte 22 Sealing material

Claims (12)

  The thickness is 5 μm to 60 μm, the porosity is 1% to 80%, and there are a large number of through holes that are isotropically communicated. In the cylindrical mandrel test, the diameter of the mandrel is gradually changed to a smaller one and bent. Sometimes, a collector for a dye-sensitized solar cell comprising a porous sintered metal thin film that does not crack on the outer surface of the bent portion up to a diameter of 6 mm.   The metal species of the porous sintered metal thin film is any one selected from Ti, W, Mo, Rh, Pt and Ta, or an alloy containing one or more of these. A current collector for a dye-sensitized solar cell according to 1. The manufacturing method of the collector material for dye-sensitized solar cells characterized by including the process of the following (a), (b), (c), and (d).
(A) A metal composition containing a metal hydride powder or dehydrogenated metal powder, a paste-like composition containing a binder component and a solvent component is applied onto a substrate, formed into a film, and then dried to volatilize the solvent component. (B) Debinding step for removing the binder component by heating the peeled dry molded body and removing the binder component (d) Debinding process Sintering step of sintering the subsequent dried molded body at 700 ° C. to 1100 ° C.   The metal raw material is titanium hydride powder, dehydrogenated titanium powder or a mixture of metal titanium powder and titanium hydride powder, and the amount of titanium hydride powder in the metal raw material is 0.1% by mass to 100% by mass. The manufacturing method of the collector material for dye-sensitized solar cells of Claim 3 characterized by these.   The said base material is PET, The manufacturing method of the collector material for dye-sensitized solar cells of Claim 3 characterized by the above-mentioned.   The method for producing a current collector material for a dye-sensitized solar cell according to claim 3, wherein, in the debinding step, a heating temperature is 150C to 450C.   In the said binder removal process, heating atmosphere is oxidizing atmosphere, The manufacturing method of the collector material for dye-sensitized solar cells of Claim 3 characterized by the above-mentioned.   The method for producing a current collector material for a dye-sensitized solar cell according to claim 3, wherein, in the sintering step, the dried molded body is placed on a setter made of a material that does not react with the metal raw material.   5. The sintering step includes a step of separating hydrogen contained in titanium hydride by heating to a temperature at which hydrogen detaches from titanium hydride under a pressure condition lower than atmospheric pressure. The manufacturing method of the collector material for dye-sensitized solar cells of description.   The method for producing a collector material for a dye-sensitized solar cell according to claim 9, wherein the heating temperature in the step of separating hydrogen contained in titanium hydride is 400C to 600C.   A transparent substrate, a conductive substrate serving as a cathode electrode, a porous semiconductor layer that is disposed between or in contact with the transparent substrate and adsorbs a dye, between the transparent substrate and the conductive substrate; 3. The dye-sensitized solar cell current collector according to claim 1, which is disposed in contact with the opposite side of the transparent semiconductor layer to the transparent substrate and serves as an anode electrode, wherein the electrolyte is sealed A dye-sensitized solar cell. A transparent substrate, a conductive substrate serving as a cathode electrode, a porous semiconductor layer that is disposed between or in contact with the transparent substrate and adsorbs a dye, between the transparent substrate and the conductive substrate; It obtains with the manufacturing method of the collector material for dye-sensitized solar cells of any one of Claims 3-10 arrange | positioned in contact with the opposite side to this transparent substrate of a porous semiconductor layer, and becoming an anode pole. A dye-sensitized solar cell including a current collector using a current collector material and having an electrolyte sealed.

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