Pt<inf>x</inf>Ni alloy nanoparticles as cathode catalyst for PEM fuel cells with enhanced catalytic activity

A series of PtxNi/C (x = 1-3) nanoparticle catalysts were prepared using a chemical reduction method, where the aim was to reduce the Pt loading and maintain high catalytic reactivity towards the oxygen reduction reaction. The catalysts were characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. The electrochemical performance of the PtxNi/C alloy catalysts was evaluated by cyclic voltammetry, steady-state measurements, and chronoamperometric testing. We found that the catalytic reactivity of Pt catalysts towards oxygen reduction can be maintained or even enhanced by partially replacing platinum with nickel. © 2009 Elsevier B.V. All rights reserved