Carbon supported Pt-Co (3:1) alloy as improved cathode electrocatalyst for direct ethanol fuel cells

In direct alcohol fuel cells, ethanol crossover causes a less serious effect compared to that of methanol because of both its smaller permeability through the Nafion((R)) membrane and its slower electrochemical oxidation kinetics on a Pt/C cathode. The main interest in direct ethanol fuel cells (DEFCs) is to find an anode catalyst with high activity for the oxidation of ethanol. However, due to the low activity of pure platinum for the oxygen reduction reaction (ORR), research on cathode electrocatalysts with improved ORR and the same or improved ethanol tolerance than that of Pt are also in progress. In this work, a commercial carbon supported Pt-Co (3:1) electrocatalyst (E-TEK) was investigated as cathode material in DEFCs and the activity compared to that of Pt. In the cathodic potential region (0.7-0.9 V versus RHE) Pt/C and Pt-Co/C showed the same activity for the oxidation of crossover ethanol. But the performance of Pt-Co/C as cathode material in DEFCs in the temperature range 60-100 degrees C is better than that of PUC both in terms of mass activity and specific activity, due to an improved activity of the alloy for oxygen reduction. (c) 2006 Elsevier B.V. All rights reserved.