JP2014192019A - Method for manufacturing electrode for fuel cell, electrode for fuel cell, method for manufacturing membrane electrode assembly for fuel cell, membrane electrode assembly for fuel cell, and polymer electrolyte fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode for a fuel cell indicating high power generation characteristics and a method for manufacturing the same while using a non-platinum catalyst as a catalyst material.SOLUTION: A first step prepares a first catalyst ink by dispersing a conductive particle and a first polymer electrolyte into a solvent. A second step embeds the conductive particle by the first polymer electrolyte by drying the first catalyst ink. A third step prepares a second catalyst ink by dispersing a mixture in which a catalyst material made of a non-platinum catalyst is added to the dried first catalyst ink and a second polymer electrolyte into the solvent. A fourth step prepares an electrode catalyst layer 2 by applying the second catalyst ink onto a transfer sheet, arranging a gas diffusion layer 4 on the applied second catalyst ink, and drying the second catalyst ink on which the gas diffusion layer 4 has been arranged and forms an electrode 6 in which the electrode catalyst layer 2 and the gas diffusion layer 4 are laminated by peeling the transfer sheet from the prepared electrode catalyst layer 2.

Description

  The present invention relates to a method for producing a fuel cell electrode, a fuel cell electrode, a method for producing a fuel cell membrane electrode assembly, a fuel cell membrane electrode assembly, and a solid polymer fuel cell.

  A fuel cell is a power generation system that generates electricity simultaneously with heat by causing a reverse reaction of electrolysis of water at an electrode containing a catalyst in a fuel gas containing hydrogen and an oxidant gas containing oxygen. This power generation system has features such as high efficiency, low environmental load, and low noise as compared with conventional power generation methods, and is attracting attention as a clean energy source in the future. There are several types of this power generation system depending on the type of ion conductor used, and those using proton conductive polymer membranes as ion conductors are called solid polymer fuel cells.

  Among fuel cells, polymer electrolyte fuel cells can be used near room temperature, so they are considered promising for use in in-vehicle power sources and household stationary power sources. In recent years, various research and development have been conducted. Yes. A polymer electrolyte fuel cell is composed of a membrane electrode assembly (hereinafter sometimes referred to as MEA (Membrane and Electrode Assembly)) in which a pair of electrodes are arranged on both sides of a polymer electrolyte membrane. The battery is sandwiched between a pair of separator plates in which a fuel gas containing hydrogen is supplied to one side and a gas flow path for supplying an oxidant gas containing oxygen to the other electrode is formed. Here, the electrode for supplying the fuel gas is called a fuel electrode, and the electrode for supplying the oxidant is called an air electrode. These electrodes are generally composed of an electrode catalyst layer formed by laminating carbon particles carrying a catalyst material such as a platinum-based noble metal and a polymer electrolyte, and a gas diffusion layer having both gas permeability and electronic conductivity. Become.

  Issues for the practical application of polymer electrolyte fuel cells include improvements in power density and durability, but the biggest issue is cost reduction. In current polymer electrolyte fuel cells, expensive platinum is used as an electrocatalyst (catalyst substance), and development of alternative materials is strongly required for full-scale spread. In particular, since the air electrode uses more platinum than the fuel electrode, the development of platinum substitute materials (non-platinum catalysts) that exhibit high oxygen reduction catalytic ability in the air electrode is actively performed.

  As a technique using a non-platinum catalyst as a catalyst substance, for example, Patent Document 1 describes a technique using a mixture of iron (transition metal) nitride and noble metal as an electrode catalyst. For example, Patent Document 2 describes a technique of using molybdenum (transition metal) nitride as an electrode catalyst. Furthermore, Patent Document 3 describes a technique using a non-platinum catalyst as a catalyst substance. In the technique described in Patent Document 3, an electrode is manufactured from a non-platinum catalyst by using a method for manufacturing an electrode from a platinum catalyst (a method described in Patent Documents 4 and 5).

JP 2005-44659 A JP 2005-63677 A JP 2008-270176 A Japanese Examined Patent Publication No. 2-48632 Japanese Patent Laid-Open No. 5-36418

  However, the techniques described in Patent Documents 1 and 2 have insufficient oxygen reducing ability and may cause the catalyst material to dissolve. Therefore, in the techniques described in Patent Documents 1 and 2, there is a possibility that power generation characteristics may be deteriorated by using a non-platinum catalyst as a catalyst material. Moreover, in the technique of the said patent document 3, the electrode is manufactured from a non-platinum catalyst using the method at the time of manufacturing an electrode from a platinum catalyst. Therefore, the technique described in Patent Document 3 has a problem that it is not suitable for manufacturing an electrode using a non-platinum catalyst as a catalyst material.

  This invention pays attention to the above points, and makes it a subject to provide the electrode for fuel cells which shows a high power generation characteristic, and its manufacturing method, using a non-platinum catalyst as a catalyst substance. Another object of the present invention is to provide a method for producing a fuel cell membrane electrode assembly including the fuel cell electrode, a fuel cell membrane electrode assembly, and a polymer electrolyte fuel cell.

As a result of intensive studies, the inventors of the present invention have completed the present invention in order to solve the above problems.
A method for producing an electrode for a fuel cell according to one aspect of the present invention includes a catalyst material comprising a non-platinum catalyst, conductive particles, and a polymer electrolyte, and the specific surface area of the conductive particles is smaller than the specific surface area of the catalyst material. A method for manufacturing a battery electrode, comprising: a first step of producing a first catalyst ink by dispersing the conductive particles and a first polymer electrolyte in a solvent; and drying the first catalyst ink. A second step of embedding the conductive particles with the first polymer electrolyte, a mixture obtained by adding the catalyst substance to the dried first catalyst ink, and a second polymer electrolyte are dispersed in a solvent. A third step of producing a second catalyst ink, applying the second catalyst ink on a transfer sheet, disposing a gas diffusion layer on the applied second catalyst ink, The disposed second catalyst ink is dried. After the, and having a fourth step of forming an electrode for a fuel cell by peeling off the transfer sheet.

In the second step, the first catalyst ink is dried so that a weight ratio of the first polymer electrolyte to the conductive particles is 10 ⁻⁴ or more and less than 0.1. Also good.
Furthermore, in the second step, the first catalyst ink may be dried at a temperature of 30 ° C. or higher and lower than 140 ° C.

Further, in the third step, the mixture of the first catalyst ink dried in the second step and the catalyst material added to the first catalyst ink and mixed without solvent is dispersed in the solvent. In this case, the second catalyst ink may be produced.
Further, in the third step, a heat treatment is performed at a temperature of 50 ° C. or more and 180 ° C. or less to a mixture obtained by adding the catalyst substance to the first catalyst ink dried in the second step and mixing it without solvent. The second catalyst ink may be prepared by dispersing the conductive particles, the catalyst material, the first polymer electrolyte, and the second polymer electrolyte that have been subjected to heat treatment in a solvent.

The catalyst material is an electrode active material for an oxygen reduction electrode used as a positive electrode of a polymer electrolyte fuel cell, and contains at least one transition metal element of tantalum, niobium, titanium, and zirconium. Also good.
Furthermore, the catalyst material may be obtained by partially oxidizing the transition metal element carbonitride in an atmosphere containing oxygen.

The fuel cell electrode of one embodiment of the present invention is manufactured by the above-described method for manufacturing a fuel cell electrode.
A method for producing a membrane electrode assembly for a fuel cell according to an aspect of the present invention is a method for producing a membrane electrode assembly in which a polymer electrolyte membrane is sandwiched between a pair of electrodes. The electrode is composed of the fuel cell electrode described above.

The membrane electrode assembly for a fuel cell according to one aspect of the present invention is manufactured by the above-described method for manufacturing a membrane electrode assembly for a fuel cell.
The solid polymer fuel cell of one embodiment of the present invention is characterized in that the membrane electrode assembly for a fuel cell is sandwiched between a pair of separators.

  In one embodiment of the present invention, the conductive particles are embedded with the first polymer electrolyte. Therefore, in one embodiment of the present invention, the proton conductivity on the surface of the conductive particles can be improved, and the reaction active point can be increased. As a result, according to one embodiment of the present invention, it is possible to provide a fuel cell electrode that exhibits high power generation characteristics while using a non-platinum catalyst as a catalyst substance, and a method for manufacturing the same. Also, one embodiment of the present invention can provide a method for producing a membrane electrode assembly for a fuel cell including the fuel cell electrode, a membrane electrode assembly for a fuel cell, and a polymer electrolyte fuel cell.

2 is an exploded cross-sectional view of a polymer electrolyte fuel cell 11. FIG. 2 is a schematic cross-sectional view of a membrane electrode assembly 12. FIG.

  Below, the membrane electrode assembly which concerns on embodiment of this invention, its manufacturing method, and a polymer electrolyte fuel cell are demonstrated. The present invention is not limited to the membrane electrode assembly described below, and modifications such as design changes can be added based on the knowledge of those skilled in the art, and such modifications are added. The embodiments are also included in the scope of the present invention.

(Configuration of polymer electrolyte fuel cell 11)
First, the configuration of the polymer electrolyte fuel cell 11 of the present embodiment will be described.
FIG. 1 is an exploded cross-sectional view of a polymer electrolyte fuel cell 11.
As shown in FIG. 1, the polymer electrolyte fuel cell 11 includes a membrane electrode assembly 12 and a pair of separators 10 that sandwich the membrane electrode assembly 12.

FIG. 2 is a schematic cross-sectional view showing the membrane electrode assembly 12 of the present embodiment.
As shown in FIG. 2, the membrane electrode assembly 12 includes a polymer electrolyte membrane 1 and a pair of electrode catalyst layers 2 and 3 (an electrode catalyst layer 2 on the air electrode side, a fuel electrode side) sandwiching the polymer electrolyte membrane 1. Electrode catalyst layer 3). Further, gas diffusion layers 4 and 5 (a gas diffusion layer 4 on the air electrode side and a gas diffusion layer 5 on the fuel electrode side) are provided outside the electrode catalyst layers 2 and 3. The electrode catalyst layer 2 and the gas diffusion layer 4 constitute an air electrode (cathode, positive electrode) 6, and the electrode catalyst layer 3 and the gas diffusion layer 5 constitute a fuel electrode (anode, negative electrode) 7. The air electrode 6 (hereinafter may be simply referred to as an electrode) includes a catalyst material made of a non-platinum catalyst, conductive particles, and a polymer. The specific surface area of the conductive particles is smaller than the specific surface area of the catalyst material.

The separator 10 includes a gas flow path 8 for gas flow and a cooling water flow path 9 for cooling water flow. The gas flow path 8 of the separator 10 on the electrode 6 side supplies a gas containing an oxidant gas (for example, oxygen). On the other hand, the gas flow path 8 of the separator 10 on the fuel electrode 7 side supplies fuel gas (for example, hydrogen gas). The polymer electrolyte fuel cell 11 generates an electromotive force between the electrode 6 and the fuel electrode 7 by causing an electrode reaction between an oxidant gas and a fuel gas in the presence of a catalyst.
In the present embodiment, an example in which a single cell fuel cell is formed as the polymer electrolyte fuel cell 11 has been shown, but other configurations may be adopted. For example, the polymer electrolyte fuel cell 11 in which a plurality of cells are stacked via the separator 10 may be formed.

(Manufacturing method of electrode 6)
Next, the manufacturing method of the electrode 6 of this embodiment is demonstrated.
The electrode 6 is manufactured by a manufacturing method having the following first to fourth steps.
First step: A step of producing a first catalyst ink by dispersing conductive particles and a first polymer electrolyte in a solvent.
Second step: a step of drying (drying) the produced first catalyst ink and embedding the conductive particles with the first polymer electrolyte.

Third step: A step of producing a second catalyst ink by dispersing a mixture obtained by adding a catalyst substance to the dried first catalyst ink and a second polymer electrolyte in a solvent.
4th process: The produced 2nd catalyst ink is apply | coated on a transfer sheet (base material), the gas diffusion layer 4 is arrange | positioned on the apply | coated 2nd catalyst ink, and the 2nd which arrange | positioned the gas diffusion layer 4 is carried out. A step of preparing the electrode catalyst layer 2 by drying (drying) the catalyst ink, peeling the transfer sheet from the prepared electrode catalyst layer 2, and forming the electrode 6 in which the electrode catalyst layer 2 and the gas diffusion layer 4 are laminated.

  The inventor of the present invention can improve the proton conductivity on the surface of the conductive particles by drying the first catalyst ink and embedding the conductive particles with the first polymer electrolyte (second step), Thereby, it discovered that the reaction active point could be increased and came to this invention. Therefore, the first catalyst ink is produced in the first step, and the conductive particles of the produced first catalyst ink are embedded in the first polymer electrolyte to increase the proton conductivity on the surface of the conductive particles, thereby allowing reaction. Increases active sites.

  Incidentally, in the conventional method for manufacturing the electrode 6 in which the conductive particles of the first catalyst ink are not embedded with the first polymer electrolyte, when the electrode catalyst layer 2 is formed, a catalyst substance having a large specific surface area is used as the polymer electrolyte. Therefore, the proton conductivity on the surface of the conductive particles is low, and the reaction active point cannot be increased. Further, even in this conventional method for producing the electrode 6, the proton conductivity on the surface of the conductive particles can be increased by increasing the concentration of the polymer electrolyte, but an excessive amount is added to the catalyst substance. It is difficult to improve the power generation characteristics.

In the second step, when the first catalyst ink is dried and the conductive particles are embedded with the first polymer electrolyte, the weight ratio between the dried conductive particles and the first polymer electrolyte is set as follows: It can be controlled by setting the ink composition of the first ink catalyst. The weight ratio between the conductive particles and the first polymer electrolyte is preferably ^{1:10 −4} or more and less than 1: 0.1. Therefore, in the second step, the first catalyst ink is dried so that the weight ratio of the first polymer electrolyte to the conductive particles is in the range of 10 ⁻⁴ or more and less than 0.1. When the weight ratio of the first polymer electrolyte to the conductive particles is less than 10 ⁻⁴ , the proton conductivity on the surface of the conductive particles does not change and it is difficult to increase the reactive site. As a result, the power generation characteristics may not be improved. In addition, when the weight ratio of the first polymer electrolyte to the conductive particles is 0.1 or more, gas diffusibility to the reaction active point is hindered, and power generation characteristics may not be improved. . In other words, in this embodiment, since the weight ratio of the first polymer electrolyte to the conductive particles is 10 ⁻⁴ or more, the proton conductivity on the surface of the conductive particles can be improved, the reaction active points can be increased, and the power generation characteristics can be improved. It can be improved. Moreover, since the weight ratio of the 1st polymer electrolyte with respect to electroconductive particle is less than 0.1, this embodiment can improve the gas diffusibility to the reaction active point, and can improve a power generation characteristic. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

In the second step, when the first catalyst ink is dried to embed the conductive particles with the first polymer electrolyte, the first catalyst ink is dried at a temperature of 30 ° C. or higher and lower than 140 ° C. Let Therefore, in the present embodiment, the first catalyst ink can be dried more appropriately.
The inventor of the present invention dried a mixture of the dried first catalyst ink and a catalyst material added thereto and the second polymer electrolyte in a solvent to prepare the second catalyst ink. By mixing the catalyst material of the first catalyst ink (conductive particles embedded with the first polymer electrolyte) and the added catalyst material without a solvent (third step), the reaction active point is increased. As a result, they have reached the present invention. Incidentally, in a method that does not perform the step of mixing the catalyst material of the first catalyst ink and the added catalyst material in the absence of a solvent, the contact property between the catalyst material and the conductive particles is low, and the reaction active point is increased. Therefore, power generation characteristics may not be improved. In other words, in this embodiment, the contact property between the catalyst substance and the conductive particles is high, and the reaction active point increases. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

  In the third step, the mixture obtained by mixing the dried catalyst substance of the first catalyst ink and the added catalyst substance without solvent is subjected to heat treatment, and the heat-treated mixture and the second polymer electrolyte are mixed. It is preferable to prepare the second catalyst ink by dispersing in a solvent. In the case where the heat treatment is not performed, there is a possibility that the reactive site is reduced in the step of producing the second catalyst ink. The heat treatment temperature is preferably 50 ° C. or higher and 180 ° C. or lower. If the temperature of the heat treatment is less than 50 ° C., the first polymer electrolyte embedding the conductive particles is dissolved in the solvent in the step of producing the second catalyst ink, and the reaction active sites formed The power generation characteristics may not improve due to the decrease. On the other hand, when the temperature of the heat treatment exceeds 180 ° C., the proton conductivity of the first polymer electrolyte embedding the conductive particles is lowered, and the power generation characteristics may not be improved. In other words, in this embodiment, since the temperature of the heat treatment is 50 ° C. or higher, it is possible to suppress the dissolution of the first polymer electrolyte embedding the conductive particles in the solvent, and to increase the reactive site, Power generation characteristics can be improved. Moreover, in this embodiment, since the temperature of heat processing exceeds 180 degreeC, the proton conductivity of the 1st polymer electrolyte which embeds electroconductive particle can be improved, and a power generation characteristic can be improved. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

  The inventor of the present invention applies the second catalyst ink onto the transfer sheet, and disposes the gas diffusion layer 4 on the applied second catalyst ink (fourth step), thereby obtaining an electrode catalyst obtained after drying. It was found that cracks in the layer 2 were suppressed, thereby increasing the reactive sites, and the present invention was reached. Non-platinum catalysts are less active than platinum catalysts. Therefore, in order to obtain power generation characteristics equivalent to those of the MEA using the conventional platinum catalyst, it is necessary to increase the coating amount of the second catalyst ink as compared with the MEA using the conventional platinum catalyst. However, when a large amount of the second catalyst ink is dried, there is a problem that the adhesion between the electrode catalyst layer 2 and the gas diffusion layer 4 is weakened, and the power generation characteristics are remarkably lowered. Therefore, the adhesion between the electrode catalyst layer 2 and the gas diffusion layer 4 is improved by applying the second catalyst ink on the transfer sheet and then disposing the gas diffusion layer 4 on the applied second catalyst ink. And high power generation characteristics can be obtained.

As the catalyst material, a non-platinum catalyst generally employed for the electrode 6 can be used. Preferably, an electrode active material for an oxygen reduction electrode used as a cathode (positive electrode) of a polymer electrolyte fuel cell, wherein a material containing at least one transition metal element of tantalum, niobium, titanium and zirconium is used. it can. Thereby, in this embodiment, high oxygen reduction performance is obtained and power generation characteristics can be improved more appropriately. More preferably, a material obtained by partially oxidizing a transition metal element carbonitride in an atmosphere containing oxygen can be used. Specifically, a substance (TaCNO) obtained by partially oxidizing tantalum carbonitride in an atmosphere containing oxygen can be used. The specific surface area of TaCNO is about 1 m ² / g or more and 100 m ² / g or less. Thereby, in this embodiment, high oxygen reduction performance is obtained and power generation characteristics can be improved more appropriately.

  Any conductive particles may be used as long as they are in the form of fine particles and have conductivity and are not eroded by the catalyst substance. However, since the carbon particles generally used for the electrode 6 have a problem that high potential corrosion occurs when starting and stopping, the conductive particles include at least one transition metal element such as tantalum, niobium, titanium, and zirconium. It is desirable to use a substance containing More preferably, transition metal element carbonitrides, nitrides, and oxynitrides can be employed. Transition metal element carbides, nitrides, and oxides can be suitably used as conductive particles because the substance itself has low catalytic activity but is less susceptible to high-potential corrosion.

Next, the membrane electrode assembly 12 and the polymer electrolyte fuel cell 11 will be described in more detail.
The polymer electrolyte membrane 1 only needs to have proton conductivity. For example, a fluorine-based polymer electrolyte membrane or a hydrocarbon-based polymer electrolyte membrane can be used. Examples of the fluorine-based polymer electrolyte membrane include Nafion (registered trademark) manufactured by DuPont, Flemion (registered trademark) manufactured by Asahi Glass Co., Ltd., Aciplex (registered trademark) manufactured by Asahi Kasei Co., Ltd., and Gore Select (registered trademark) manufactured by Gore. ) Etc. can be used. In particular, a Nafion (registered trademark) material manufactured by DuPont can be suitably used as the fluorine-based polymer electrolyte membrane. As the hydrocarbon polymer electrolyte membrane, for example, an electrolyte membrane such as sulfonated polyether ketone, sulfonated polyethersulfone, sulfonated polyetherethersulfone, sulfonated polysulfide, and sulfonated polyphenylene can be used.

  The electrode catalyst layer 2 is formed using a first catalyst ink and a second catalyst ink (hereinafter, collectively referred to as catalyst ink). The catalyst ink includes at least a catalyst substance, a first polymer electrolyte or a second polymer electrolyte (hereinafter sometimes collectively referred to as a polymer electrolyte) and a solvent. The polymer electrolyte of the catalyst ink may be any one having proton conductivity. For example, the same material as the polymer electrolyte membrane 1 can be used. More specifically, a fluorine-based polymer electrolyte or a hydrocarbon-based polymer electrolyte can be used. As the fluorine-based polymer electrolyte, for example, a Nafion (registered trademark) material manufactured by DuPont can be used. In particular, a Nafion (registered trademark) material manufactured by DuPont can be suitably used. In addition, as the hydrocarbon polymer electrolyte, for example, electrolytes such as sulfonated polyether ketone, sulfonated polyethersulfone, sulfonated polyetherethersulfone, sulfonated polysulfide, and sulfonated polyphenylene can be used. The polymer electrolyte is preferably made of the same material as the polymer electrolyte membrane 1 in consideration of the adhesion between the electrode catalyst layer 2 and the polymer electrolyte membrane 1. Further, the first polymer electrolyte and the second polymer electrolyte may be made of the same material or different materials.

  The solvent for the catalyst ink may be any solvent that does not erode the catalyst substance-supporting particles and the polymer electrolyte and can dissolve or disperse the polymer electrolyte in a highly fluid state. However, it is desirable that at least a volatile organic solvent is contained. For example, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, pentaanol, acetone, methyl ethyl ketone, Ketone solvents such as pentanone, methyl isobutyl ketone, heptanone, cyclohexanone, methyl cyclohexanone, acetonyl acetone, diisobutyl ketone, tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, ether solvents such as anisole, methoxy toluene, dibutyl ether, other dimethylformamide, Such as dimethylacetamide, N-methylpyrrolidone, ethylene glycol, diethylene glycol, diacetone alcohol, 1-methoxy-2-propanol Or the like can be used in the polar solvent. Moreover, you may use the solvent of a catalyst ink individually by 1 type or in combination of 2 or more types (mixed one).

Further, a lower alcohol may be used as a solvent for the catalyst ink. However, lower alcohols have a high risk of ignition. Therefore, when a lower alcohol is used as a solvent for the catalyst ink, it is preferable to use a mixed solvent of a lower alcohol and water. Furthermore, as a solvent for the catalyst ink, for example, water that is compatible with the polymer electrolyte may be added. The amount of water added may be any as long as the polymer electrolyte is not separated to cause white turbidity or gelation. Further, the solvent of the first catalyst ink and the solvent of the second catalyst ink may be the same material or different materials.
The catalyst ink may further contain a dispersant in order to disperse the catalyst substance and the conductive particles. As the dispersant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or the like can be used.

  Examples of the anionic surfactant include alkyl ether carboxylate, ether carboxylate, alkanoyl sarcosine, alkanoyl glutamate, acyl glutamate, oleic acid / N-methyltaurine, potassium oleate / diethanolamine salt, alkyl ether sulfate, Triethanolamine salt, polyoxyethylene alkyl ether sulfate / triethanolamine salt, amine salt of special modified polyether ester acid, amine salt of higher fatty acid derivative, amine salt of special modified polyester acid, amine of high molecular weight polyether ester acid Salt, special modified phosphate ester amine salt, high molecular weight polyester acid amidoamine salt, special fatty acid derivative amidoamine salt, higher fatty acid alkylamine salt, high molecular weight polycarboxylic acid Carboxylic acid type surfactants such as midamine salt, sodium laurate, sodium stearate, sodium oleate, dialkylsulfosuccinate, dialkylsulfosuccinate, 1,2-bis (alkoxycarbonyl) -1-ethanesulfonate , Alkyl sulfonate, alkyl sulfonate, paraffin sulfonate, α-olefin sulfonate, linear alkyl benzene sulfonate, alkyl benzene sulfonate, polynaphthyl methane sulfonate, polynaphthyl methane sulfonate, naphthalene sulfonate-formalin condensate, alkyl naphthalene sulfonate, Alkanoylmethyl tauride, lauryl sulfate sodium salt, cetyl sulfate sodium salt, stearyl sulfate sodium salt, oleyl Sulfate ester sodium salt, lauryl ether sulfate ester salt, sodium alkylbenzene sulfonate, oil-soluble alkylbenzene sulfonate, α-olefin sulfonate and other surfactants, alkyl sulfate ester salts, alkyl sulfate salts, alkyl sulfates, Sulfate ester surfactants such as alkyl ether sulfate, polyoxyethylene alkyl ether sulfate, alkyl polyethoxy sulfate, polyglycol ether sulfate, alkyl polyoxyethylene sulfate, sulfated oil, highly sulfated oil, phosphoric acid (mono Or di) alkyl salt, (mono or di) alkyl phosphate, (mono or di) alkyl phosphate ester salt, alkyl polyoxyethylene phosphate, alkyl ether phosphate, alkyl Polyethoxy / phosphate, polyoxyethylene alkyl ether, alkylphenyl phosphate / polyoxyethylene salt, alkylphenyl ether / phosphate, alkylphenyl / polyethoxy phosphate, polyoxyethylene / alkylphenyl / ether phosphate, higher alcohol phosphorus Phosphate-type surfactants such as acid monoester disodium salt, higher alcohol phosphoric acid diester disodium salt and zinc dialkyldithiophosphate can be used.

  Examples of the cationic surfactant include benzyldimethyl {2- [2- (P-1,1,3,3-tetramethylbutylphenoxy) ethoxy] ethyl} ammonium chloride, octadecylamine acetate, tetradecylamine acetic acid. Salt, octadecyltrimethylammonium chloride, tallow trimethylammonium chloride, dodecyltrimethylammonium chloride, coconut trimethylammonium chloride, hexadecyltrimethylammonium chloride, behenyltrimethylammonium chloride, coconut dimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, octadecyldimethylbenzylammonium chloride Chloride, dioleyldimethylammonium chloride, 1-hydroxy Ethyl-2-tallow imidazoline quaternary salt, 2-heptadecenyl-hydroxyethyl imidazoline, stearamide ethyl diethylamine acetate, stearamide ethyl diethylamine hydrochloride, triethanolamine monostearate formate, alkyl pyridium salt, higher alkyl Amine ethylene oxide adducts, polyacrylamide amine salts, modified polyacrylamide amine salts, perfluoroalkyl quaternary ammonium iodides and the like can be used.

  Examples of amphoteric surfactants include dimethyl coconut betaine, dimethyl lauryl betaine, sodium laurylaminoethyl glycine, sodium lauryl aminopropionate, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, amide betaine, imidazolinium betaine, lecithin, 3- [Ω-fluoroalkanoyl-N-ethylamino] -1-propanesulfonic acid sodium, N- [3- (perfluorooctanesulfonamido) propyl] -N, N-dimethyl-N-carboxymethyleneammonium betaine, etc. Can do.

  Examples of the nonionic surfactant include coconut fatty acid diethanolamide (1: 2 type), coconut fatty acid diethanolamide (1: 1 type), bovine fatty acid diethanolamide (1: 2 type), and bovine fatty acid diethanolamide (1: 2). 1 type), oleic acid diethanolamide (1: 1 type), hydroxyethyl lauryl amine, polyethylene glycol lauryl amine, polyethylene glycol palm amine, polyethylene glycol stearyl amine, polyethylene glycol beef tallow amine, polyethylene glycol beef tallow propylene diamine, polyethylene glycol dioleyl amine , Dimethyl lauryl amine oxide, dimethyl stearyl amine oxide, dihydroxyethyl lauryl amine oxide, perfluoroalkylamine oxide, polyvinyl chloride Pyrrolidone, higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, glycerin fatty acid ester, pentaerythritol fatty acid ester, sorbit fatty acid ester, sorbitan fatty acid ester, Sugar fatty acid esters and the like can be used.

  Among the above surfactants, sulfonic acid type surfactants such as alkylbenzene sulfonic acid, oil-soluble alkylbenzene sulfonic acid, α-olefin sulfonic acid, sodium alkylbenzene sulfonate, oil-soluble alkylbenzene sulfonate, α-olefin sulfonate, etc. Can be suitably used as a dispersant in consideration of the carbon dispersion effect, the change in catalyst performance due to the remaining of the dispersant, and the like.

  In addition, the catalyst ink may be subjected to a dispersion process as necessary. The viscosity and particle size of the catalyst ink can be controlled by the conditions of the catalyst ink dispersion treatment. Distributed processing can be performed using various apparatuses. Therefore, the distributed processing method is not particularly limited. For example, a ball mill or roll mill process, a shear mill process, a wet mill process, an ultrasonic dispersion process, or the like can be used for the dispersion process. Moreover, you may use the homogenizer etc. which stir with centrifugal force.

  If the solid content in the catalyst ink is too large, the viscosity of the catalyst ink becomes high, so that the surface of the electrode catalyst layer 2 tends to crack. On the other hand, if the solid content in the catalyst ink is too small, the film formation rate is very slow and the productivity is lowered. Therefore, the solid content in the catalyst ink is preferably 1 to 50% by mass. In addition, the solid content is composed of a catalyst substance, carbon particles, a peroxide decomposition catalyst, and a polymer electrolyte. Get higher. On the other hand, when the content of carbon particles in the solid content is reduced, the viscosity of the catalyst ink is lowered even with the same solid content. Therefore, the proportion of carbon particles in the solid content is preferably 10 to 80% by mass. The viscosity of the catalyst ink is preferably about 0.1 to 500 cP (0.0001 to 0.5 Pa · s), more preferably 5 to 100 cP (0.005 to 0.1 Pa · s). Further, the viscosity of the catalyst ink can be controlled by adding a dispersing agent when the catalyst ink is dispersed.

  Further, the catalyst ink may further contain a pore forming agent in order to form pores in the electrode catalyst layer 2. The pore-forming agent is removed after the electrode catalyst layer 2 is formed. As the contrast agent, an acid, an alkali, a substance soluble in water, a sublimation substance such as camphor, a thermal decomposition substance, or the like can be used. For example, when a substance that is soluble in water is used, the contrast agent may be removed with water generated during power generation.

  Examples of substances that are soluble in acid, alkali, and water include acid-soluble inorganic salts such as calcium carbonate, barium carbonate, magnesium carbonate, magnesium sulfate, and magnesium oxide, inorganic salts soluble in alkaline aqueous solutions such as alumina, silica gel, and silica sol, and aluminum. Metals soluble in acids or alkalis such as zinc, tin, nickel and iron, water-soluble inorganic salts such as sodium chloride, potassium chloride, ammonium chloride, sodium carbonate, sodium sulfate and monosodium phosphate, polyvinyl alcohol, polyethylene glycol Water-soluble organic compounds such as can be used. Further, the pore-forming agent may be used alone or in combination of two or more, but it is preferable to use two or more in combination.

  The conductive particles embedded with the first polymer electrolyte are coated with a first catalyst ink in which the conductive particles and the first polymer electrolyte are dispersed in a solvent on a substrate (transfer sheet). This catalyst ink can be dried. As the transfer sheet, a material having good transferability can be used. For example, fluorine such as ethylene tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroperfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), etc. Series resins can be used. Also, for example, polymer sheets such as polyimide, polyethylene terephthalate, polyamide (nylon), polysulfone, polyethersulfone, polyphenylene sulfide, polyether ether ketone, polyetherimide, polyarylate, polyethylene naphthalate, polymer film Can be used. As a method for applying the catalyst ink, a doctor blade method, a dipping method, a screen printing method, a roll coating method, a spray method, or the like can be used. For example, the doctor blade method is preferable because the amount of the catalyst ink is large and it is easy to increase the thickness of the electrode catalyst layer 2 obtained by drying. The conductive particles embedded with the first polymer electrolyte are the first conductive particles embedded with the first polymer electrolyte by spraying the first catalyst ink in a dry atmosphere. This catalyst ink can also be produced by drying.

As the gas diffusion layers 4 and 5, a material having gas diffusibility and conductivity can be used. For example, porous carbon materials such as carbon cloth, carbon paper, and nonwoven fabric can be used.
As the separator 10, a carbon type or a metal type can be used. In the polymer electrolyte fuel cell 11, the separator 10 can be manufactured by assembling other accompanying devices such as a gas supply device and a cooling device.

(Example)
Next, the manufacturing method (first to fourth steps) of the electrode 6 of the present embodiment will be described with specific examples and comparative examples. In addition, this invention is not limited to the Example described below.
(First step: Preparation of first catalyst ink)
In the first step, conductive particles (TaCN, specific surface area 2 m ² / g) and a 20% by mass polymer electrolyte solution (trade name: Nafion (registered trademark), manufactured by DuPont, first polymer electrolyte) are used as solvents. Mixed in. The mass ratio between the conductive particles and the first polymer electrolyte was 1: 0.01. The solvent included ultrapure water and 1-propanol. The volume ratio of ultrapure water to 1-propanol was 1: 1. Subsequently, in the first step, a dispersion treatment was performed with a ball mill in a solvent in which conductive particles and a 20% by mass polymer electrolyte solution were mixed. Thereby, the 1st catalyst ink was produced in the 1st process. As the ball mill pot and balls, those made of zirconia were used. The solid content of the first catalyst ink was 14% by mass.

(Second Step: Method for Forming Conductive Particles Embedded with First Polymer Electrolyte)
In the second step, the first catalyst ink was applied onto the substrate with a doctor blade. A PTFE sheet was used as the substrate. Subsequently, in the second step, the applied first catalyst ink was dried at 80 ° C. for 5 minutes in the air atmosphere. Thus, in the second step, conductive particles embedded with the first polymer electrolyte were produced. Subsequently, in the second step, the conductive particles embedded with the first polymer electrolyte, that is, the dried first catalyst ink was collected from the substrate.

(Third Step: Mixing and Heat Treatment of Conductive Particles Embedded with First Polymer Electrolyte and Catalyst Material)
In the third step, the conductive particles embedded with the first polymer electrolyte and the catalyst material (TaCNO, specific surface area 10 m ² / g) were mixed by a ball mill. Thus, in the third step, the catalyst material was added to the dried first catalyst ink. As the ball mill pot and balls, those made of zirconia were used. The mass ratio of the conductive particles to the catalyst material was 1: 1. The conductive particles embedded with the first polymer electrolyte and the catalyst material were mixed without a solvent.

(Third step: Preparation of second catalyst ink)
Subsequently, in the third step, the conductive particles embedded with the first polymer electrolyte, the mixture obtained by adding the catalyst substance to the dried first catalyst ink, and heat treatment, and the 20 mass% polymer The electrolyte solution (second polymer electrolyte) was mixed in a solvent. The mass ratio of the conductive particles, the catalyst material, and the second polymer electrolyte was 1: 1: 0.7. The solvent contained ultrapure water and 1-propanol. The volume ratio of ultrapure water to 1-propanol was 1: 1. Subsequently, in the third step, the mixed solvent was dispersed with a ball mill. Thereby, the 2nd catalyst ink was produced in the 3rd process. A ball mill pot and balls were made of zirconia. The solid content of the second catalyst ink was 14% by mass.

(4th process: Preparation method of the electrode 6)
In the fourth step, the second catalyst ink was applied onto the transfer sheet (base material) by a doctor blade. A PTFE sheet was used as the transfer sheet. Subsequently, in the fourth step, carbon paper on which a mesh layer was formed as the gas diffusion layer 4 was disposed on the applied second catalyst ink. Subsequently, in the fourth step, the second catalyst ink on which the carbon paper was arranged was dried at 80 ° C. for 10 minutes in the air atmosphere. Thereby, the electrode catalyst 2 was produced in the 4th process. Subsequently, in the fourth step, the transfer sheet was peeled from the produced electrode catalyst layer 2. Thereby, in the 4th process, electrode 6 in which electrode catalyst layer 2 and gas diffusion layer 4 were laminated was produced. The thickness of the electrode catalyst layer 2 was adjusted so that the amount of the catalyst material supported was 10 mg / cm ² .

(Comparative example)
(Preparation of catalyst ink)
Conductive particles, a catalyst substance, and a 20% by mass polymer electrolyte solution were mixed in a solvent. The mass ratio of the conductive particles, the catalyst substance, and the polymer electrolyte was 1: 1: 0.7. The solvent included ultrapure water and 1-propanol. The volume ratio of ultrapure water to 1-propanol was 1: 1. Subsequently, in the first step, the mixture prepared by mixing was subjected to dispersion treatment with a ball mill. Thereby, a catalyst ink was prepared. As the ball mill pot and balls, those made of zirconia were used. The solid content of the catalyst ink was 14% by mass.

(Method for producing electrode 6)
The prepared catalyst ink was applied to a substrate in the same manner as in the example, and the applied catalyst ink was dried. Thereby, the electrode catalyst layer 2 was produced. The thickness of the electrode catalyst layer 2 was adjusted so that the amount of the catalyst material supported was 10 mg / cm ² . As the substrate, the same transfer sheet (PET sheet) as in the example was used. Subsequently, carbon paper in which a target layer was formed as the gas diffusion layer 4 was disposed on the produced electrode catalyst layer 2. Thereby, the electrode 6 was produced.

(Method for Producing Fuel Electrode 7 of Examples and Comparative Examples)
A platinum-supported carbon catalyst (trade name: TEC10E50E, manufactured by Tanaka Kikinzoku Kogyo Co., Ltd.) having a platinum support amount of 50% by mass and a 20% by mass polymer electrolyte solution were mixed in a solvent. The mass ratio of carbon in the platinum-supporting carbon to the polymer electrolyte was 1: 1. The solvent included ultrapure water and 1-propanol. The volume ratio of ultrapure water to 1-propanol was 1: 1. Then, the dispersion process was performed with the ball mill to the mixture produced by mixing. The dispersion time was 60 minutes. This produced the catalyst ink. The solid content of the catalyst ink was 10% by mass. Subsequently, the prepared catalyst ink was applied to the substrate by the same method as that for the electrode 6, and the applied catalyst ink was dried. Thereby, the electrode catalyst layer 3 was produced. The thickness of the electrode catalyst layer 3 was adjusted so that the amount of catalyst material supported was 0.3 mg / cm ² . Subsequently, carbon paper in which a target layer was formed as the gas diffusion layer 5 was disposed on the produced electrode catalyst layer 3. Thereby, the fuel electrode 7 in which the electrode catalyst layer 3 and the gas diffusion layer 5 were laminated was produced.

(Method for Producing Membrane / Electrode Assembly 12 of Examples and Comparative Examples)
The electrode 6 and the fuel electrode 7 produced in the example and the comparative example were punched into a 5 cm ² square. Subsequently, a transfer sheet was disposed so as to face both surfaces of the polymer electrolyte membrane 1 (trade name: Nafion (registered trademark), manufactured by DuPont). Subsequently, the polymer electrolyte membrane 1 on which the transfer sheet was arranged was hot pressed at 130 ° C. for 10 minutes. Thereby, the membrane electrode assembly 12 was produced. Subsequently, the produced membrane electrode assembly 12 was sandwiched between a pair of separators 10. In this way, a single cell polymer electrolyte fuel cell 11 was produced.

(Evaluation)
(Evaluation conditions)
The power generation characteristics of the polymer electrolyte fuel cell 11 using the electrode 6 produced in the example and the polymer electrolyte fuel cell 11 using the electrode 6 produced in the comparative example were evaluated. The power generation characteristics were evaluated using a fuel cell measurement device at a cell temperature of 80 ° C. and under conditions of 100% RH for both the fuel electrode 7 (anode) and the air electrode 6 (cathode). In the power generation characteristics evaluation, pure hydrogen was used as the fuel gas and pure oxygen was used as the oxidant gas, and the flow rate was controlled at a constant flow rate.

(Measurement result)
The polymer electrolyte fuel cell 11 produced in the example showed better power generation performance than the polymer electrolyte fuel cell 11 produced in the comparative example. In particular, the power generation performance in the vicinity of 0.6 V is improved, and the polymer electrolyte fuel cell 11 produced in the example is approximately 4.7 times as much as the polymer electrolyte fuel cell 11 produced in the comparative example. Showed performance. This is because, in the polymer electrolyte fuel cell 11 produced in the example, the proton conductivity on the surface of the conductive particles was increased by embedding the conductive particles with the first polymer electrolyte, and the reaction active points increased. Inferred. The polymer electrolyte fuel cell 11 produced in the example has high adhesion between the electrode catalyst layer 2 and the gas diffusion layer 4, and it is presumed that high power generation characteristics were obtained. On the other hand, the polymer electrolyte fuel cell 11 produced in the comparative example disperses the conductive particles, the catalyst material, and the polymer electrolyte in the solvent in one step, so that the catalyst particles have a specific surface area larger than that of the conductive particles. On the other hand, it is inferred that sufficient proton conductivity was not ensured on the surface of the conductive particles by preferentially adsorbing the polymer electrolyte. The polymer electrolyte fuel cell 11 produced in the comparative example has low adhesion between the electrode catalyst layer 2 and the gas diffusion layer 4, and it is presumed that the power generation characteristics are thereby lowered.
In this embodiment, the air electrode (electrode) 6 of FIGS. 1 and 2 constitutes a fuel cell electrode. The membrane electrode assembly 12 of FIGS. 1 and 2 constitutes a fuel cell membrane electrode assembly.

(Effect of this embodiment)
This embodiment has the following effects.
(1) In the first step, the first catalyst ink is prepared by dispersing conductive particles and the first polymer electrolyte in a solvent. Subsequently, in the second step, the first catalyst ink is dried to embed the conductive particles with the first polymer electrolyte. Subsequently, in the third step, a mixture obtained by adding a catalyst material made of a non-platinum catalyst to the dried first catalyst ink and the second polymer electrolyte are dispersed in a solvent to produce a second catalyst ink. . Subsequently, in the fourth step, the second catalyst ink is applied onto the transfer sheet, the gas diffusion layer 4 is disposed on the applied second catalyst ink, and the second catalyst ink in which the gas diffusion layer 4 is disposed. Is dried to produce an electrode catalyst layer 2, and the transfer sheet is peeled from the produced electrode catalyst layer 2 to form an electrode 6 in which the electrode catalyst layer 2 and the gas diffusion layer 4 are laminated.

  Thus, in the present embodiment, the conductive particles are embedded with the first polymer electrolyte. Therefore, in this embodiment, the proton conductivity on the surface of the conductive particles can be improved, and the reactive site can be increased. As a result, in the present embodiment, it is possible to provide an electrode 6 that exhibits high power generation characteristics while using a non-platinum catalyst as a catalyst material.

(2) In the second step, the first catalyst ink is dried so that the weight ratio of the first polymer electrolyte to the conductive particles is 10 ⁻⁴ or more and less than 0.1.
Thereby, in this embodiment, since the weight ratio of the first polymer electrolyte to the conductive particles is 10 ⁻⁴ or more, the proton conductivity on the surface of the conductive particles can be improved, the reaction active points can be increased, and the power generation characteristics can be improved. It can be improved. Moreover, since the weight ratio of the 1st polymer electrolyte with respect to electroconductive particle is less than 0.1, this embodiment can improve the gas diffusibility to the reaction active point, and can improve a power generation characteristic. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

(3) In the second step, the first catalyst ink is dried at a temperature of 30 ° C. or higher and lower than 140 ° C.
Thereby, in this embodiment, the 1st catalyst ink can be dried more appropriately.
(4) In the third step, a mixture obtained by adding a catalyst substance to the dried first catalyst ink and mixing it in the absence of solvent and the second polymer electrolyte are dispersed in a solvent to obtain the second catalyst ink. Make it.
Thereby, in this embodiment, the contact property of a catalyst substance and electroconductive particle is high, and a reaction active point increases. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

(5) In the third step, a heat treatment is performed at a temperature of 50 ° C. or more and 180 ° C. or less to a mixture obtained by adding a catalyst substance to the dried first catalyst ink and mixing it without solvent. Subsequently, in the third step, the second catalyst ink is prepared by dispersing the heat-treated conductive particles, the catalyst substance, the first polymer electrolyte, and the second polymer electrolyte in a solvent.
Thereby, in this embodiment, since the temperature of heat processing is 50 degreeC or more, it can suppress that the 1st polymer electrolyte which embeds electroconductive particle melt | dissolves in a solvent, can also increase a reactive site, Power generation characteristics can be improved. Moreover, in this embodiment, since the temperature of heat processing exceeds 180 degreeC, the proton conductivity of the 1st polymer electrolyte which embeds electroconductive particle can be improved, and a power generation characteristic can be improved. Therefore, in this embodiment, the power generation characteristics can be improved more appropriately.

(6) The catalyst material is an electrode active material for an oxygen reduction electrode used as a positive electrode of the polymer electrolyte fuel cell 11, and contains at least one transition metal element of tantalum, niobium, titanium and zirconium.
Thereby, in this embodiment, a power generation characteristic can be improved more appropriately.
(7) The catalyst material is obtained by partially oxidizing a transition metal element carbonitride in an oxygen-containing atmosphere.
Thereby, in this embodiment, a power generation characteristic can be improved more appropriately.

(8) The electrode 6 was manufactured by the manufacturing method of said (1)-(7).
Thereby, in this embodiment, the electrode 6 which shows a high electric power generation characteristic can be provided.
(9) Of the pair of electrodes 6 and 7, the electrode 6 on the positive electrode side is the electrode 6 of the above (8).
Thereby, in this embodiment, the manufacturing cost of the membrane electrode assembly 12 can be reduced more.

(10) The membrane / electrode assembly 12 was produced by the method for producing the membrane / electrode assembly 12 of (9) above.
Thereby, in this embodiment, the membrane electrode assembly 12 provided with the electrode 6 which shows a high electric power generation characteristic can be provided.
(11) The polymer electrolyte fuel cell 11 includes the membrane electrode assembly 12 of (10) above.
Thereby, in this embodiment, the polymer electrolyte fuel cell 11 provided with the electrode 6 which shows a high electric power generation characteristic can be provided.

  One aspect of the present invention is a method for producing an electrode for a fuel cell, which includes a catalyst material, conductive particles, and a polymer electrolyte, and has a specific surface area of the conductive particles smaller than the specific surface area of the catalyst material. And a step of embedding with the polymer electrolyte. Accordingly, in one embodiment of the present invention, the proton conductivity on the surface of the conductive particles can be improved, and the reactive site can be increased. Therefore, in one embodiment of the present invention, a fuel cell electrode exhibiting high power generation characteristics can be provided.

Another embodiment of the present invention is a method for producing an electrode for a fuel cell that includes a catalyst material, conductive particles, and a polymer electrolyte, and wherein the specific surface area of the conductive particles is smaller than the specific surface area of the catalyst material. The method includes a step of applying a catalyst ink to a transfer sheet and disposing a gas diffusion layer on the applied catalyst ink. Thereby, in 1 aspect of this invention, the adhesiveness of an electrode catalyst layer and a gas diffusion layer can be improved by arrange | positioning a gas diffusion layer on the apply | coated catalyst ink. As a result, in one embodiment of the present invention, a fuel cell electrode exhibiting high power generation characteristics can be provided. Also, one embodiment of the present invention can provide a method for producing a membrane electrode assembly for a fuel cell including the fuel cell electrode, a membrane electrode assembly for a fuel cell, and a polymer electrolyte fuel cell.
Therefore, in one aspect of the present invention, in a fuel cell electrode using a non-platinum catalyst as a catalyst material, the potential of the catalyst material can be extracted more than a conventional method for producing a fuel cell electrode. Since it has an effect, it has high industrial utility value.

DESCRIPTION OF SYMBOLS 1 Solid polymer electrolyte membrane 2 Electrode catalyst layer 3 Electrode catalyst layer 4 Gas diffusion layer 5 Gas diffusion layer 6 Air electrode (electrode for fuel cells)
7 Fuel electrode 8 Gas flow path 9 Cooling water flow path 10 Separator 11 Polymer electrolyte fuel cell 12 Membrane electrode assembly (membrane electrode assembly for fuel cell)

Claims (11)

A method for producing a fuel cell electrode comprising a catalyst material comprising a non-platinum catalyst, conductive particles and a polymer electrolyte, wherein the specific surface area of the conductive particles is smaller than the specific surface area of the catalyst material,
A first step of producing a first catalyst ink by dispersing the conductive particles and the first polymer electrolyte in a solvent;
A second step of drying the first catalyst ink and embedding the conductive particles with the first polymer electrolyte;
A third step of producing a second catalyst ink by dispersing a mixture obtained by adding the catalyst substance to the dried first catalyst ink and a second polymer electrolyte in a solvent;
The second catalyst ink is applied onto a transfer sheet, a gas diffusion layer is disposed on the applied second catalyst ink, and the second catalyst ink having the gas diffusion layer disposed thereon is dried to form an electrode catalyst. And a fourth step of forming a fuel cell electrode in which the electrode catalyst layer and the gas diffusion layer are laminated by peeling off the transfer sheet from the produced electrode catalyst layer. Manufacturing method of electrode for fuel cell. In the second step, the first catalyst ink is dried so that a weight ratio of the first polymer electrolyte to the conductive particles is 10 ⁻⁴ or more and less than 0.1. A method for producing a fuel cell electrode according to claim 1.   3. The method for producing a fuel cell electrode according to claim 1, wherein in the second step, the first catalyst ink is dried at a temperature of 30 ° C. or higher and lower than 140 ° C. 4.   In the third step, a mixture obtained by adding the catalyst substance to the dried first catalyst ink and mixing without solvent and the second polymer electrolyte are dispersed in a solvent, and the second catalyst is dispersed. The method for producing an electrode for a fuel cell according to any one of claims 1 to 3, wherein an ink is produced.   In the third step, the catalyst material is added to the dried first catalyst ink and mixed in the absence of a solvent, and then the mixture is heat-treated at a temperature of 50 ° C. or more and 180 ° C. or less. 5. The method for producing a fuel cell electrode according to claim 4, wherein the second catalyst ink is prepared by dispersing the mixture and the second polymer electrolyte in a solvent.   The catalyst material is an electrode active material for an oxygen reduction electrode used as a positive electrode of a polymer electrolyte fuel cell, and includes at least one transition metal element of tantalum, niobium, titanium, and zirconium. The method for producing a fuel cell electrode according to any one of claims 1 to 5.   The method for producing a fuel cell electrode according to claim 6, wherein the catalyst material is obtained by partially oxidizing the transition metal element carbonitride in an atmosphere containing oxygen.   An electrode for a fuel cell, which is manufactured by the method for manufacturing an electrode for a fuel cell according to any one of claims 1 to 7. A method for producing a membrane electrode assembly for a fuel cell in which a polymer electrolyte membrane is sandwiched between a pair of electrodes,
The method for producing a membrane electrode assembly for a fuel cell, wherein the positive electrode of the pair of electrodes is the fuel cell electrode according to claim 8.   A fuel cell membrane electrode assembly manufactured by the method for manufacturing a fuel cell membrane electrode assembly according to claim 9.   11. A polymer electrolyte fuel cell comprising the fuel cell membrane electrode assembly according to claim 10 and a pair of separators sandwiching the fuel cell membrane electrode assembly.

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