Abstract: This electrode catalyst layer for fuel cells is provided with: an electrode catalyst that comprises a conductive carrier and platinum-containing metal particles supported on the surface of the conductive carrier; and an ionomer that covers the electrode catalyst. This electrode catalyst layer for fuel cells is characterized in that the average thickness of the ionomer is 2.4 nm or less. This electrode catalyst layer for fuel cells is capable of having a good balance between proton transport properties and transport properties for a gas such as an oxidant gas or a fuel gas even in cases where the amount of supported platinum is decreased. In addition, an electrode for fuel cells, a membrane electrode assembly for fuel cells, and a fuel cell, each having good current-voltage characteristics, can be obtained using the above-described electrode catalyst layer for fuel cells.

Abstract: The present invention relates to an electrode catalyst for fuel cell containing a catalyst carrier having carbon as a main component and a catalytic metal carried on the catalyst carrier, wherein the electrode catalyst for fuel cell has a ratio R? (D?/G intensity ratio) of a peak intensity of D? band (D? intensity) measured in the vicinity of 1620 cm?1 to a peak intensity of G band (G intensity) measured in the vicinity of 1580 cm?1 by Raman spectroscopy of more than 0.6 and 0.8 or less, and satisfies at least one of the (a) to (d). According to the present invention, an electrode catalyst for fuel cell excellent in gas transportability is provided.

Abstract: The present invention is to provide a carbon powder that can provide a catalyst having excellent durability and a catalyst. A carbon powder for catalyst of the present invention is a carbon powder containing as a main component carbon, which has a BET specific surface area per unit weight of 900 m2/g or greater, and a ratio R? (D?/G intensity ratio) of peak intensity for a D?-band (D? intensity) measured in the vicinity of 1620 cm?1 to peak intensity for a G-band (G intensity) measured in the vicinity of 1580 cm?1 by Raman spectroscopy of 0.6 or less.

Abstract: [Object] Provided is a catalyst having excellent gas transportability. [Solving Means] Disclosed is a catalyst comprising a catalyst support and a catalyst metal supported on the catalyst support, wherein the catalyst includes pores having a radius of less than 1 nm and pores having a radius of 1 nm or more, wherein a pore volume of the pores having a radius of less than 1 nm is 0.3 cc/g support or more or a mode radius of a pore distribution of the pores having a radius of less than 1 nm is 0.3 nm or more and less than 1 nm, and wherein the catalyst metal is supported inside the pores having a radius of 1 nm or more.

Abstract: The object of the present invention is to provide a catalyst having an excellent catalyst activity. In the present invention, a catalyst is configured to include a catalyst support and a catalyst metal supported on the catalyst support, wherein a mode radius of pore distribution of pores of the catalyst is 1 nm or more and less than 5 nm, wherein the mode radius is equal to or less than an average particle radius of the catalyst metal, and wherein a pore volume of the pores is 0.4 cc/g support or more.

Abstract: [Object] Provided is a catalyst having an excellent gas transportability. [Solving Means] Disclosed is a catalyst including a catalyst metal and a support, wherein the catalyst includes pores having a radius of 1 nm or more and less than 5 nm, a pore volume of the pores is 0.8 cc/g support or more, and the catalyst metal has a specific surface area of 30 m2/g support or less.

Abstract: The present invention has an object to provide a catalyst having excellent oxygen reduction reaction activity. The present invention relates to a catalyst comprising a catalyst support and a catalyst metal supported on the catalyst support, wherein a specific surface area of the catalyst per support weight is 715 m2/g support or more or a covering ratio of the catalyst metal with an electrolyte is less than 0.5, and an amount of an acidic group of the catalyst per support weight is 0.75 mmol/g support or less.

Abstract: [Object] Provided is a catalyst having a high catalytic activity. [Solving Means] Disclosed is a catalyst comprising a catalyst support and a catalyst metal supported on the catalyst support, wherein the catalyst support includes pores having a radius of less than 1 nm and pores having a radius of 1 nm or more, a surface area formed by the pores having a radius of less than 1 nm is equal to or larger than a surface area formed by the pores having a radius of 1 nm or more, and an average particle diameter of the catalyst metal is 2.8 nm or more.

Abstract: Object Provided is a catalyst having an excellent durability and being capable of lowering the cost of a fuel cell. Solving Means Disclosed is a catalyst configured to include a support and alloy particles including platinum and a metal component other than platinum supported on the support, wherein the catalyst includes mesopores having a radius of 1 to 10 nm originated from the support, wherein a mode radius of the mesopores is in a range of 2.5 to 10 nm, and wherein the alloy particles have a catalyst function, and at least a portion of the alloy particles is supported inside the mesopores.

Abstract: [Object] To provide a gas diffusion electrode capable of a high current density operation of a fuel cell. [Solving means] A gas diffusion electrode including a hydrophilic porous layer having an electrically conductive material and an ion conductive material; and a catalyst layer adjacent to the hydrophilic porous layer, wherein a water transport resistance of the hydrophilic porous layer is smaller than a water transport resistance of the catalyst layer.

Abstract: A fuel cell electrode catalyst layer (13) of the preset invention includes: a catalyst (131b); a support (131a) that supports the catalyst; and two or more proton-conductive materials (133) different in dry mass value per mole of a proton-donating group, the proton-conductive materials being in contact with at least a part of the catalyst and at least a part of the support. Then, a proton-conductive material in which a dry mass value per mole of the proton-donating group is highest among the proton-conductive materials is in contact with at least a part of the catalyst, and has a largest contact ratio with a surface of the catalyst.

Abstract: To provide a catalyst layer for a fuel cell, which exhibits excellent power generation performance even in the case of reducing the used amount of a catalyst. It is an electrode catalyst layer for a fuel cell comprising a catalyst, a porous carrier for supporting the above-mentioned catalyst, and a polymer electrolyte, in which a mode diameter of the pore distribution of the above-mentioned porous carrier is 4 to 20 nm, and the above-mentioned catalyst is supported in a pore with a pore diameter of 4 to 20 nm of the above-mentioned porous carrier.

Abstract: This electrode catalyst layer for fuel cells is provided with: an electrode catalyst that comprises a conductive carrier and platinum-containing metal particles supported on the surface of the conductive carrier; and an ionomer that covers the electrode catalyst. This electrode catalyst layer for fuel cells is characterized in that the average thickness of the ionomer is 2.4 nm or less. This electrode catalyst layer for fuel cells is capable of having a good balance between proton transport properties and transport properties for a gas such as an oxidant gas or a fuel gas even in cases where the amount of supported platinum is decreased. In addition, an electrode for fuel cells, a membrane electrode assembly for fuel cells, and a fuel cell, each having good current-voltage characteristics, can be obtained using the above-described electrode catalyst layer for fuel cells.

Abstract: Provided is an electrocatalyst for solid polymer fuel cells capable of increasing the active surface area for reactions in a catalyst component, increasing the utilization efficiency of the catalyst, and reducing the amount of expensive precious metal catalyst used. Also provided are a membrane electrode assembly that uses this electrocatalyst and a solid polymer fuel cell. An electrocatalyst for a solid polymer fuel cell is provided with a catalyst and solid proton conducting material. A liquid conductive material retention part that retains a liquid proton conducting material that connects the catalyst and solid proton conducting material is provided between the same. The surface area of the catalyst exposed within the liquid conductive material retention part is larger than the surface area of the catalyst in contact with the solid proton conducting material.

Abstract: A catalyst layer 2 is formed by conductive particles 4 carrying catalyst particles 5, and a boundary layer 3 is disposed adjacent to the catalyst layer 2 and is positioned between a portion which is easily contacted with an oxygen gas and the catalyst layer 2. The boundary layer 3 is formed by the conductive particles 4 carrying the catalyst particles 5 and a catalyst-carrying amount in the boundary layer 3 is smaller than a catalyst-carrying amount in the catalyst layer 2, and a hydrophilic treatment is carried out on the conductive particles 4 of the boundary layer 3 by a hydrophilic material, such that the hydrophilic characteristics of the conductive particles of the boundary layer are higher than that of the catalyst layer.

Abstract: For a combination of a solid polymer electrolyte membrane 107, catalytic layers 111 and 113 disposed on both sides of the solid polymer electrolyte membrane 107, gas diffusion layers 112 and 114 disposed outside the catalytic layers 111 and 113, and separators 103 and 104 disposed outside the gas diffusion layers 112 and 114, the catalytic layer 113 to be cathode-sided includes a carbon carrier 117 composed of carbon having a mean lattice plane spacing d002 of [002] planes calculated from an X-ray diffraction within a range of 0.343 nm to 0.358 nm, a crystallite size Lc within a range of 3 nm to 10 nm, and a specific surface area within a range of 200 m2/g to 300 m2/g, catalyst particles 115 containing platinum supported on the carbon carrier 117, and an electrolyte 116.

Abstract: A fuel cell comprises a cathode catalyst layer and an anode catalyst layer disposed on each surface of an electrolyte membrane, an oxidant gas passage facing the cathode catalyst layer, and a fuel gas passage facing the anode catalyst layer. The cathode catalyst layer contains a metal catalyst. In a region (A), in which the differential electric potential between the cathode catalyst layer and the electrolyte membrane is larger than in another region, the metal catalyst content of the cathode catalyst layer or the specific surface area of the metal catalyst in the form of minute particles is increased, and thus a deterioration in electric power generation efficiency caused by melting of the metal catalyst due to the large differential electric potential is prevented.

Abstract: [Summary] [Object] To provide a hydrophilic porous layer for a fuel cell that improves a sub-zero temperature starting ability of the fuel cell. [Solving means] A hydrophilic porous layer comprising electrically conductive material—hydrophilic material aggregates each including hydrophilic materials and electrically conductive materials that intimately contact to one another, the hydrophilic materials being mutually connected to one another to form in the hydrophilic materials a continuous transport path for water, the electrically conductive material—hydrophilic material aggregates forming therebetween a transport path for water vapor, which is characterized in that when it is above ?40° C., a water transport resistance Rwater of the water transport path is larger than a water vapor transport resistance Rgas of the water vapor transport path.

Abstract: [Object] To provide a gas diffusion electrode capable of a high current density operation of a fuel cell. [Solving means] A gas diffusion electrode including a hydrophilic porous layer having an electrically conductive material and an ion conductive material; and a catalyst layer adjacent to the hydrophilic porous layer, wherein a water transport resistance of the hydrophilic porous layer is smaller than a water transport resistance of the catalyst layer.

Abstract: A fuel cell comprises a cathode catalyst layer and an anode catalyst layer disposed on each surface of an electrolyte membrane, an oxidant gas passage facing the cathode catalyst layer, and a fuel gas passage facing the anode catalyst layer. The cathode catalyst layer contains a metal catalyst. In a region (A), in which the differential electric potential between the cathode catalyst layer and the electrolyte membrane is larger than in another region, the metal catalyst content of the cathode catalyst layer or the specific surface area of the metal catalyst in the form of minute particles is increased, and thus a deterioration in electric power generation efficiency caused by melting of the metal catalyst due to the large differential electric potential is prevented.