Toyota Jidosha Kabushiki Kaisha

Audi Ag

Hiroko Kimura

Naoki Takehiro

Manabu Kato

Kazutaka Kimura

Makoto Adachi

Keiichi Kaneko

Tatsuya Arai

Noriyuki Kitao

Takumi Taniguchi

Atsuo Iio

Koshi Sekizawa

The present invention is to provide a method for producing a catalyst for fuel cells with excellent durability, and a fuel cell comprising a catalyst for fuel cells produced by the production method. Disclosed is a method for producing a catalyst for fuel cells, the catalyst comprising fine catalyst particles, each of which comprises a palladium-containing core particle and a platinum-containing outermost layer covering the core particle, and carbon supports on which the fine catalyst particles are supported, wherein the method comprises the steps of: preparing carbon supports on which palladium-containing particles are supported; fining the carbon supports; and covering the palladium-containing particles with a platinum-containing outermost layer after the fining step.

Method for producing catalyst for fuel cells, and fuel cell containing catalyst for fuel cells produced by the production method

The present invention is to provide a method for producing core-shell catalyst particles with high catalytic activity per unit mass of platinum. Disclosed is a method for producing core-shell catalyst particles including a core containing palladium and a shell containing platinum and covering the shell, wherein the method includes: a step of depositing copper on the surface of the palladium-containing particles by applying a potential that is nobler than the oxidation-reduction potential of copper to the palladium-containing particles in a copper ion-containing electrolyte, and a step of forming the shell by, after the copper deposition step and inside the reaction system kept at &#x2212;3&#xb0; C. or more and 10&#xb0; C. or less, substituting the copper deposited on the surface of the palladium-containing particles with platinum by bringing the copper into contact with a platinum ion-containing solution in which platinum ions and a reaction inhibitor that inhibits a substitution reaction between the copper and the platinum, are contained.

Method for producing core-shell catalyst particles

The present invention is to provide fine catalyst particles with better catalytic performance than ever before and a carbon-supported catalyst with better catalytic performance than ever before. Disclosed is a method for producing fine catalyst particles, comprising: a potential applying step of applying a potential to the fine palladium-containing particles in a first dispersion, until a peak indicating a Pd{111} surface in a reduction wave of a cyclic voltammogram becomes larger than a peak indicating a Pd{110} or Pd{100} surface in the reduction wave of the cyclic voltammogram; a copper covering step of covering at least part of the fine palladium-containing particle with copper by preparing a second dispersion by mixing the first dispersion and a copper-containing solution after the potential applying step, and applying a potential that is nobler than the oxidation-reduction potential of copper to the fine palladium-containing particles in the second dispersion; and a platinum covering step of covering at least part of the fine palladium-containing particle with platinum by mixing the second dispersion and a platinum-containing solution after the copper covering step.

Method for producing fine catalyst particles and method for producing carbon-supported catalyst

An object of the present invention is to provide a production method which can increase the activity of a catalyst particle comprising a core particle and an outermost layer, the core particle comprising at least one of palladium and a palladium alloy, and the outermost layer comprising at least one of platinum and a platinum alloy and covering the core particle. The method is for producing a catalyst for fuel cells, in which a catalyst particle is supported by an electroconductive carrier, the method comprising the steps of: preparing a supported catalyst in which a catalyst particle comprising a core particle and an outermost layer is supported by an electroconductive carrier, the core particle comprising at least one of palladium and a palladium alloy, and the outermost layer comprising at least one of platinum and a platinum alloy and covering the core particle; acid treatment to bring the supported catalyst into contact with an acid solution which dissolves palladium more preferentially than platinum; and firing the supported catalyst at 80&#xb0; C. or more and less than 200&#xb0; C. in a reducing gas atmosphere after the acid treatment step.

Method for producing a catalyst for fuel cells

A particle size distribution creating method includes a particle size range determining step, an integrating step of integrating the frequency of appearance of particles within the particle size range determined in the particle size range determining step, a division point determining step of determining particle sizes that provide division points, using the integral of the frequency of appearance obtained in the integrating step, and a typical point determining step of determining the minimum particle size, maximum particle size and the particle sizes of the division points as typical points. This method is characterized by assuming a particle size distribution which contains particles having the particle sizes of the respective typical points and is plotted such that the frequency of appearance of the particles having the particle size of each of the typical points is equal to the integral over each of the regions defined by the typical points, and obtaining the assumed particle size distribution as a particle size distribution model.

Method of predicting degradation of fuel cell catalyst using the method of creating particle size distribution model

Method of controlling fuel cell using the method of predicting degradation of fuel cell catalyst

The present invention provides a fuel cell which is capable of improving electric power generation efficiency at a time of high-temperature operation. The fuel cellcomprising: a membrane electrode assembly; and a pair of gas separators,sandwiching the membrane electrode assemblytherebetween, wherein at least one of the gas separator(s)and/orcomprises a compact layer(s)and/orwhich is capable of preventing permeation of fluid and a porous layer (s)and/orwhich allows permeation of fluid, and the porous layer(s)and/oris impregnated with a water-soluble liquid having higher boiling point than that of water.

Fuel cell

A fuel cell including a single fuel cell which includes a membrane electrode including a polymer electrolyte membrane, an anode electrode on one surface of the polymer electrolyte membrane, and a cathode electrode on another surface of the polymer electrolyte membrane, the anode electrode including an anode catalyst layer and a gas diffusion layer and the cathode electrode including a cathode catalyst layer and a gas diffusion layer. At least one of the anode cathode catalyst layers includes core-shell type catalyst particles, each having a core and a shell covering the core and including a shell metallic material. At least one of the polymer electrolyte membrane, anode catalyst layer, gas diffusion layer at the anode side, cathode catalyst layer and gas diffusion layer at the cathode side includes metallic nanoparticles having an average particle diameter different from that of the core-shell type catalyst particles and including the shell metallic material.

Method of creating particle size distribution model, method of predicting degradation of fuel cell catalyst using the method of creating particle size distribution model, and method of controlling fuel cell using the method of predicting degradation of fuel cell catalyst

Growing community of inventors

Susono, Japan

Hiroko Kimura