Efficient C-C bond cleavage in ethanol electrooxidation on porous Pt catalysts

For increasing the energy conversion efficiency of ethanol in direct oxidation fuel cells, cleavage of C-C bond to form the final product CO(2) is a predominate prerequisite. In this work, we show that high efficiency of C-C bond cleavage in ethanol electrooxidation can be achieved on porous Pt catalysts. The porous Pt films of different roughness factor (ratio of the real surface area to the geometric one) were electrochemically deposited on Au substrates and characterized by SEM, XRD and electrochemical methods. The electrochemical results show that the deposited porous Pt films possess considerable electrocatalytic activity toward the oxidation of ethanol in acidic medium. In situ FTIR results reveal that the ratio of final product CO(2) via efficient C-C bond cleavage to soluble intermediates (acetaldehyde and acetic acid) significantly increases with the increase of surface roughness of the Pt film electrodes. The present results demonstrate that porous Pt catalysts with larger roughness factor can play an important role in efficient utilization of ethanol both as fuel and Pt noble metal in direct ethanol oxidation fuel cells, due to the optimal surface morphology of Pt catalyst. (C) 2011 Elsevier B.V. All rights reserved.