MEASURING METHOD FOR REACTION SPECIFIC SURFACE AREA AND UTILIZATION FACTOR OF NOBLE METAL CATALYST AT SOLID POLYMER-TYPE FUEL CELL AND CATALYST LAYER FOR ELECTRODE FOR SOLID POLYMER-TYPE FUEL CELL

摘要

PROBLEM TO BE SOLVED: To precisely compute the reaction specific surface area and the utilization factor of a noble metal catalyst at a solid polymer-type duel cell and to obtain a catalyst layer at the solid polymer-type fuel cell of high characteristic on the basis of the utilization factor. SOLUTION: A carbon powder which carries a noble metal catalyst covered with a polymer electrolyte is reduced by hydrogen at 150 to 250% deg.C, carbon monoxide is adsorbed, and the specific surface area of the noble metal catalyst which is not covered with the polymer electrolyte is measured. In the same manner, the total specific surface area of a noble metal catalyst carried by a carbon powder is measured, the reaction specific surface area and the utilization factor of a noble metal catalyst at a solid polymer-type fuel cell are found, and a catalyst layer at the solid polymer-type fuel cell of a high characteristic is obtained.