Carbon-Supported Pt-Pd Alloy as a Methanol-Tolerant-Oxygen-Reduction Electro-Catalyst for DMFCs

摘要

Methanol-tolerant Pt-Pd alloy catalysts supported on to carbon with varying Pt:Pd atomic ratios of 1:1, 2:1 and 3:1 are prepared by a novel wet-chemical method and characterized using powder XRD, FESEM and EDAX techniques. The optimum atomic weight ratio of Pt to Pd in the carbon-supported alloy catalyst as established by linear-sweep voltammetry (LSV) and cell-polarization studies is found to be 2:1. A direct methanol fuel cell (DMFC) employing the carbon-supported Pt-Pd(2:l) alloy catalyst as the cathode catalyst delivers a peak-power density of 115 mW/cm~2 at 70°C as compared to the peak-power density value of 60 mW/cm~2 obtained with the DMFC employing carbon-supported Pt (Pt/C) catalyst operating under similar conditions.