Nitrogen-doped graphene supported Cu-Ag2.9 nanoparticles as efficient methanol tolerant cathode for oxygen reduction

Abstract Highly dispersed nanoparticles (NPs) of Cu, Ag and their composites are obtained on nitrogen-doped graphene nanosheets (N-GNS) using a microwave-assisted polyol reduction method. Structural, electrochemical and electrocatalytic surface characterization of materials have been carried out by TEM, XRD, XPS, cyclic (CV) and linear sweep (LSV) voltammetries. The study shows that the crystallites of the Cu-Ag composite follow the face-centered cubic (fcc) crystal structure. Further, the catalytic activities of Cu/N-GNS and Ag/N-GNS towards oxygen reduction reaction (ORR) are greatly enhanced when Cu and Ag are dispersed on the N-GNS surface in 1:2.9 M ratio. The active composite material does not oxidize methanol practically and has outstanding stability under ORR condition.