Effect of precursor nature on the performance of palladium–cobalt electrocatalysts for direct methanol fuel cells

The performance of platinum-free palladium–cobalt catalysts in oxygen reduction was investigated for a direct methanol fuel cell. The dependence of catalytic activity on precursor nature was determined for two classes of precursors; namely, palladium chloride and palladium nitrate. The nitrate precursor exhibits much higher catalytic performance than the chloride precursor. X-ray absorption fine structure (XAFS) spectra indicate that the structure of palladium catalyst prepared from nitrate is much closer to Pd3Co structure that can explain high catalytic activity. The MEA prepared from the nitrate catalyst achieved the peak power density of 125 mW cm−2, which is much higher than 19 mW cm−2 measured on the cell prepared from the chloride catalyst.