Graphene supported Pt–Ni nanoparticles for oxygen reduction reaction in acidic electrolyte

Abstract

The design of high performance oxygen reduction reaction (ORR) electrocatalysts play an important role in the commercialization of polymer electrolyte membrane fuel cells. The morphology, structure, and composition of the support material significantly affect the catalytic activity of the fuel cell catalyst. In this work, we report a systematic and comparative study of the effects of the support morphology for Pt–Ni nanoparticles for the ORR. The effect of the support morphology on the electrocatalytic oxygen reduction reaction was investigated. Pt–Ni alloy catalysts were characterized using various physico-chemical techniques, such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Pt–Ni alloy nanoparticles were deposited uniformly on a graphene support and their oxygen reduction activities were evaluated in an acid electrolyte. The ORR activity of Pt–Ni supported on graphene was also compared with Pt–Ni supported on Vulcan carbon XC-72 and carbon nanotubes. The electrocatalytic activity and stability of Pt–Ni alloy catalysts were studied using cyclic voltammetry, linear sweep voltammetry, rotating disk electrode, and rotating ring disk electrode techniques. The results demonstrate that the graphene supported Pt–Ni catalyst showed the highest ORR activity among the three evaluated catalysts.