Pt1−xCox nanoparticles as cathode catalyst for proton exchange membrane fuel cells with enhanced catalytic activity

Nanosize carbon-supported Pt1−xCox (x = 0.2, 0.3, and 0.45) electrocatalysts were prepared by a chemical reduction method using sodium borohydride (NaBH4) as the reduction agent. Transmission electron microscopy examination showed uniform dispersion of Pt1−xCox alloy catalysts on carbon matrix, with the particle size less than 10 nm. The electrochemical characteristics of Pt1−xCox alloy catalysts were studied by cyclic voltammetry, linear sweep voltammetry, and chronoamperometric testing. The as-prepared Pt1−xCox alloy nanoparticles could be promising cathode catalysts for oxygen reduction in proton exchange membrane fuel cells with the feature of much reduced cost, but significantly increased catalytic activity.