CoxNiy-decorated graphene as novel, stable and super effective non-precious electro-catalyst for methanol oxidation

Abstract

Graphene and alloy structure can overcome the main problem facing the non-precious electro-catalysts; low performance and poor stability. In this study, CoxNiy-decorated graphene is introduced as novel, super effective and stable non-precious electro-catalyst for methanol oxidation. The obtained results have indicated that utilizing graphene as a support strongly enhances the electro-catalytic activity as the current density was doubled ten times, moreover a negative onset potential (−40mV vs. Ag/AgCl) was obtained which is a distinct progress in the non-precious electro-catalysts research field. The electronic structure which is controlled by the alloy composition showed strong influence on the electro-catalytic activity; Co0.2Ni0.2 alloy nanoparticles revealed the best performance while Co0.1Ni0.3 nanoparticles were the worst. Due to the alloy structure, the introduced graphene-supported electro-catalyst reveals distinguished stability. In-situ decoration of graphene by CoxNiy alloy nanoparticle is utilized to produce the introduced electro-catalyst. Briefly, cobalt acetate and nickel acetate were added to the reaction media during graphene preparation using a modified chemical route. Later on, the resultant material was calcined in argon atmosphere at 850°C. The utilized physicochemical characteristics affirmed formation of multi-layer graphene sheets decorated by solid solution CoxNiy alloy nanoparticle.