Cobalt nanoparticle decorated graphene aerogel for efficient oxygen reduction reaction electrocatalysis

Transition metals have attracted particular research interest for sustainable ORR electrocatalysis but zero-valent ones have been often ignored. In this work metallic cobalt nanoparticle decorated graphene aerogel (CoNPs/rGO aerogel) was synthesized via a facile hydrothermal reaction, followed by thermal annealing in reducing H2 atmosphere. As-prepared CoNPs/rGO aerogel demonstrates commercial Pt/C-comparable ORR activity through a predominant four-electron pathway, as well as excellent durability and methanol tolerance superior to Pt/C in alkaline medium. This work suggests that metallic cobalt nanoparticle is highly efficient to boost the ORR activity of neighboring carbon besides various cobalt compounds.