Facile one-pot synthesis of a nitrogen-doped mesoporous carbon architecture with cobalt oxides encapsulated in graphitic layers as a robust bicatalyst for oxygen reduction and evolution reactions

The development of future energy technology relies deeply on the design of cheap, sustainable and efficient systems for energy conversion and storage. As for the widespread oxygen electrode reactions, exploiting high efficiency and stable catalysts to boost both oxygen reduction (ORR) and evolution reactions (OER) seems to be a paramount mission. Here, we report a nitrogen-doped mesoporous carbon material with cobalt oxide nanoparticles encapsulated in the graphitic layers via a facile one-pot synthesis. Strikingly, the as-fabricated Co–N/C 800 affords a low reversible overvoltage of 0.96 V between ORR and OER, surpassing 270, 390 and 460 mV in potential over 20 wt% Pt/C, RuO2 and IrO2, which makes it a high performance non-precious metal bicatalyst for reversible oxygen electrode reactions.