Fabrication of a Glassy Carbon Electrode Coated with Ni-Au Nanoparticles and Its Application on Electrolytic Oxidation of Methanol in Fuel Cells

Bimetallic Ni-Au nanoparticles were synthesized and immobilized on the surface of a glassy carbon (GC) electrode using Nafion polymer as a binder. The obtained electrode then was conditioned in an alkaline solution by cyclic voltammetric method in potential range 100 -700 mV (vs. Ag/AgCl). Physicochemical characterizations of the synthesized nanoparticles were carried out by transmission electron microscopy (TEM), and X-ray diffraction (XRD); and their electrochemical activities were investigated by using cyclic voltammetry (CV). The results showed that Ni-Au modified electrode had a greater efficiency and a higher activity towards oxidation of methanol than that of monometallic Ni catalyst. It is believed that these effects are arisen from the greater oxidation abilities of Ni (ΙΙΙ) and Au (III) ions that are formed by surface reaction of the coated nanoparticles. In addition to this finding, the current study also investigated the effects of various parameters such as the mole ratio of Ni/Au, potential scan rate and methanol concentration on the electrolytic performance of the modified electrode.