Investigation of carbon-supported Au hollow nanospheres as electrocatalyst for electrooxidation of sodium borohydride

A carbon-supported Au hollow nanospheres composite electrocatalyst was prepared in aqueous solution with Co nanoparticles as sacrificial templates at room temperature. The electrocatalyst was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersion X-ray (EDX) spectra and electrochemical tests. The results showed that carbon-supported Au hollow nanospheres were porous, and composed of discrete Au nanoparticles with the crystallite size of about 6 nm. For comparison, the electrocatalytic performances of both carbon-supported Au hollow nanospheres and carbon-supported Au solid nanoparticles on borohydride electrooxidation in fuel cells were investigated by cyclic voltammetry, chronoamperometry, and chronopotentiometry. The fundamental electrochemical test results indicated that the electrocatalytic activity of carbon-supported Au hollow nanospheres is much better than that of carbon-supported Au solid nanoparticles.