A Non-Precious Electrocatalyst for Oxygen Reduction Based on Simple Heat-Treated Precursors

摘要

An active, non-precious catalyst for electrochemical oxygen reduction was made by heat-treating simple precursors. The current density obtained in an H_2/O_2 polymer electrolyte fuel cell (PEFC) was as high as 0.34 A/cm_(MEA)~2 at 0.65 V. The oxygen-reduction activities of catalysts prepared at different temperatures over the range 800-1050℃ were shown to be equivalent by the rotating ring-disk electrode (RRDE) method. The nitrogen content, however, was observed by XPS to be highly variable with preparation temperature. Thus, in contrast to some reports in the literature, the surface nitrogen content was not strongly correlated to performance. The nature of the active site(s) is currently under investigation.