LAUSR

Abstract In this study, a novel hierarchical porous network of Pt51Pd49 alloy-integrated graphene nanosheet as active catalyst towards ethanol oxidation was fabricated using electroless deposition followed by chemical vapour deposition for the first time. Such materials were obtained as a three-dimensional continuous and non-order porous architecture with good dispersion and uniformity of the ultrasmall Pt51Pd49 nanoalloy particles (∼3 nm) within the graphene nanosheets. As an electrocatalyst, it exhibited excellent catalytic behaviour towards ethanol oxidation with superior conversion, long-term stability and better tolerance towards intermediate's poisoning effect, as compared to commercial Pt black product. The results were associated with the enhanced electroactive surface area and mass transfer possibility of the catalyst due to the formation of an unique porous nanostructure for Pt51Pd49 alloys. In addition, the coating effect of graphene nanosheets over Pt51Pd49 alloy nanoparticles avoided aggregation and dissolution, possibly allowing full utilization of the active sites from all nanoparticles, and thus efficiently improving charge transfer ability and working stability of the catalyst. Owning high quality, good electrochemical performance, and ease of synthesis, the as-synthesized catalyst opens an interesting nanoarchitecture class for efficiently catalyzing ethanol oxidation in fuel cells.