Evaluation of semiconducting tin oxide as an electrocatalyst support

Abstract

Semiconducting tin oxide prepared from chloride salts has been evaluated as an electrocatalyst support. The support had an electrical conductivity comparable to that of conventional active carbon supports. Platinum catalysts prepared on tin oxide were found to have low activity for methanol electro-oxidation. Characterisation by X-ray diffraction, temperature-programmed reduction and cyclic voltammetry revealed that the platinum for the greater part was not present as platinum metal. It is proposed that the calcination of the platinum catalyst in air resulted in a strong interaction or compound formation between the platinum species and the tin oxide, rendering the platinum difficult to reduce.