Electrocatalytic activity and stability of Pt supported on Sb-doped SnO2 nanoparticles for direct alcohol fuel cells

Electrocatalytic activities and stabilities of Pt supported on Sb-doped SnO2 (ATO) were examined for methanol (MOR) and ethanol (EOR) oxidation reactions. Pt colloidal particles were deposited on ATO nanoparticles (Pt/ATO) with various amounts of Pt loading. The prepared electrocatalysts were characterized by X-ray diffraction, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy, thermogravimetric analysis, and cyclic voltammetry. Electrochemical activities of the Pt/ATO for CO oxidation, MOR, and EOR were compared with those of Pt supported on carbon (Pt/C). The MOR and EOR activities of the Pt/ATO were enhanced over those of the Pt/C with decreasing amounts of Pt loaded on ATO. The Pt/ATO exhibited much higher electrochemical and thermal stabilities than the Pt/C. According to TEM, the growth rate of Pt particles was lower in the Pt/ATO than in the Pt/C. The ATO nanoparticles appear to be promising support materials that promote electrochemical reactions and stabilize catalyst particles in direct alcohol fuel cells.