Abstract
A fuel cell is an electrochemical cell that converts a source fuel into an electrical current It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions, and environmental pollution throughout world. In this study, different sized metallic and bimetallic nanoparticles (AuNPs, Fe@AuNPs, Ag@AuNPs) were synthesized on graphene oxide sheets and their electrocatalytic activities for methanol oxidation were investigated. All the catalysts were characterized by transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Electrochemical measurements are performed to compare the catalytic efficiencies of methanol oxidation. Experimental results demonstrated that graphene oxide-supported bimetallic nanoparticles enhanced electrochemical efficiency for methanol electro-oxidation with regard to diffusion efficiency, oxidation potential and forward oxidation peak current. Graphene oxide-supported Ag@AuNPs, in comparison to graphene oxide-supported Fe@AuNPs and AuNPs, showed the more efficiency for methanol electro-oxidation. (C) 2013 Elsevier B.V. All rights reserved.