Recent advances in Fe (or Co)/N/C electrocatalysts for the oxygen reduction reaction in polymer electrolyte membrane fuel cells

Abstract

Exploring cheap and stable electrocatalysts to replace Pt for the oxygen reduction reaction (ORR) is now the key issue for the large-scale application of fuel cells, especially polymer electrolyte membrane fuel cells. The recent emergence of Fe (or Co)/N/C catalysts has created tremendous opportunities for the development of non-precious metal catalysts for ORR in acidic media and thus presents great potential in the application of fuel cells. In this review, we summarize the recent advances in the Fe (or Co)/N/C catalysts for ORR in acidic media that have demonstrated comparable activity to the commercial Pt catalyst. The synthesis, structural characterization and underlying mechanism of Fe (or Co)/N/C catalysts are discussed. In addition, we highlight the interesting microstructures of the active site, new synthesis approaches, and the catalytic performances tuned by nonmetal heteroatom dopants. Finally, perspectives on the challenges and future opportunities are also discussed.