Carbon-Supported Platinum Catalysts for Direct Alcohol Fuel Cell Anode

Abstract

To achieve maximum utilization of precious platinum catalyst for ethanol electro-oxidation the highest possible surface to volume ratio of the dispersed metal is desirable. In this respect we have investigated the roughness factor of carbon-supported platinum catalysts prepared at different deposition current densities. It is observed that lowering the deposition current density can considerably reduce platinum particle size and thereby increase the roughness factor of the electrode. Further, use of PTFE in the deposition bath results in highly porous platinum dispersion. The combined effect of these two factors significantly enhances the electrocatalytic activity of platinum catalysts towards ethanol oxidation. Cyclic voltammetry, steady state polarization, and electrochemical impedance spectroscopy are used to investigate the kinetics and mechanism of ethanol electro-oxidation. SEM-EDX analysis has been performed to investigate the morphology and chemical composition of the synthesized catalyst layers.