Enhanced activity in ethanol oxidation of Pt<inf>3</inf>Sn electrocatalysts synthesized by microwave irradiation

Abstract

High surface area carbon supported Pt and Pt3Sn catalysts were synthesized by microwave irradiation and investigated in the ethanol electro-oxidation reaction. The catalysts were obtained using a modified polyol method in an ethylene glycol solution and were characterized in terms of structure, morphology and composition by employing XRD, STM and EDX techniques. The diffraction peaks of Pt3Sn/C catalyst in XRD patterns are shifted to lower 2θ values with respect to the corresponding peaks at Pt/C catalyst as a consequence of alloy formation between Pt and Sn. Particle size analysis from STM and XRD shows that Pt and Pt3Sn clusters are of a small diameter (~2 nm) with a narrow size distribution. Pt3Sn/C catalyst is highly active in ethanol oxidation with the onset potential shifted for ~150 mV to more negative values and with ~2 times higher currents in comparison to Pt/C.