Platinum deposited on TiO2-C and SnO2-C composites for methanol oxidation and oxygen reduction

Electrocatalytic activities and stabilities of Pt supported on SnO2-carbon and TiO2-carbon as electrocatalysts were examined for methanol oxidation and oxygen reduction reactions. The Pt/oxide-C catalysts were synthesized by photo-deposition method at RT. The samples prepared were characterized by X-ray diffraction, TEM analysis, cyclic and lineal voltammetry, CO stripping and chronoamperometry techniques. Electrochemical activities of Pt/oxide-C for methanol oxidation reaction (MOR) and methanol tolerance for oxygen reduction were compared with those of Pt/C (Pt-Etek). The MOR activity of Pt/SnO2-C was enhanced over those of the Pt/TiO2-C and Pt/C at different concentrations due to the small platinum particles size. Pt-Sn interaction produce changes in the platinum electronic properties that improve the electrochemical activity towards the methanol oxidation and stability to the methanol presence. The SnO2-C composite appear to be a promising support material that promote electrochemical reactions and stabilize catalytic particles in direct alcohol fuel cells.