Supermicroporous carbons with nitrogen and defect co-doped as high-efficient oxygen reduction catalysts in both alkaline and acidic medium

Abstract

A nitrogen and defect co-doped carbonaceous electrocatalyst with uniform supermicroporous architecture toward oxygen reduction reaction (ORR) was successfully synthesized by using zinc gluconate as an intramolecular defect formation agent. The resultant novel electrocatalysts possess two kinds of active sites (nitrogen and defects) and facilitate the catalytic species to approach the three phase interfaces, which accelerate the breaking of oxygen bonds and effectively prevent the active sites from protonation. Owing to the synergistic effects of nitrogen-doping and topological defects, the supermicroporous structure enriched metal-free catalyst exhibits a superior ORR activity with a half-wave potential up to 0.89 V (vs. RHE) in 0.1 M KOH and 0.77 V (vs. RHE) in 0.1 M HClO4, which has tremendous application potentials in metal-air batteries and proton exchange membrane fuel cells.