Abstract: Provided is a catalyst that can exhibit high activity. The catalyst is an electrode catalyst having catalytic metals supported on a catalyst support, in which the catalytic metals include platinum and a metal component other than platinum; the electrode catalyst has mesopores having a mode radius of pore distribution of mesopores having a radius of 1 nm or more, of 1 nm or more and less than 2.5 nm; alloy microparticles of platinum and the metal component other than platinum are supported inside the mesopores; and a molar content ratio of platinum with respect to the metal component other than platinum in the alloy microparticles supported inside the mesopores is 1.0 to 10.0.

Abstract: Provided is a catalyst that can exhibit high activity. The catalyst is an electrode catalyst having catalytic metals supported on a catalyst support, in which the catalytic metals include platinum and a metal component other than platinum; the electrode catalyst has mesopores having a mode radius of pore distribution of mesopores having a radius of 1 nm or more, of 1 nm or more and less than 2.5 nm; alloy microparticles of platinum and the metal component other than platinum are supported inside the mesopores; and a molar content ratio of platinum with respect to the metal component other than platinum in the alloy microparticles supported inside the mesopores is 1.0 to 10.0.

Abstract: The present invention provides a catalyst for a polymer electrolyte fuel cell including catalyst particles made of platinum supported on a carbon powder carrier, wherein the carbon powder carrier includes 0.7 to 3.0 mmol/g (based on the weight of the carrier) of a hydrophilic group bonded thereto; and the platinum particles have an average particle size of 3.5 to 8.0 nm and the platinum specific surface area based on CO adsorption (COMSA) of 40 to 100 m2/g. The catalyst for a polymer electrolyte fuel cell according to the present invention is a catalyst excellent in initial activity and satisfactory in durability.

Abstract: The present invention provides a catalyst for a polymer electrolyte fuel cell including catalyst particles made of platinum supported on a carbon powder carrier, wherein the carbon powder carrier includes 0.7 to 3.0 mmol/g (based on the weight of the carrier) of a hydrophilic group bonded thereto; and the platinum particles have an average particle size of 3.5 to 8.0 nm and the platinum specific surface area based on CO adsorption (COMSA) of 40 to 100 m2/g. The catalyst for a polymer electrolyte fuel cell according to the present invention is a catalyst excellent in initial activity and satisfactory in durability.