Carbon-supported Pt-Fe alloy as a methanol-resistant oxygen-reduction catalyst for direct methanol fuel cells

摘要

Crossover of methanol from the anode to the cathode through the polymer–electrolyte membrane in solid–polymer–electrolyte direct methanol fuel cells constitutes a significant loss in their performance. Pt/C and Pt–Fe/C electrocatalysts have been characterized by X-ray diffraction, and X-ray photoelectron and X-ray absorption spectroscopies in conjunction with electrochemistry. It is found that Pt–Fe/C alloy crystallizing in an ordered face centered tetragonal crystal structure with higher proportions of active-platinum sites and a completely different nearest neighbour environment than Pt/C exhibits significantly high oxygen-reduction activity in the presence of methanol while Pt/C shows a methanol poisoning effect under similar conditions.