Supramolecular gel-assisted synthesis Co2P particles anchored in multielement co-doped graphene as efficient bifunctional electrocatalysts for oxygen reduction and evolution

Abstract

Developing highly cost-effective bifunctional oxygen electrode catalysts for renewable energy technologies (e.g. metal-air batteries and fuel cells) is highly desirable but remains challenging. In this work, we demonstrate a novel composite of Co2P particles anchored in cobalt, nitrogen and phosphorus co-doped graphene nanosheets (Co2P@CoNPG) prepared via supramolecular gel-assisted strategy. In virtue of the positive synergistic effect originating from the Co2P, Co-Nx active sites and N/P co-functionalized graphene in the composite, the optimized Co2P@CoNPG-900 exhibits superior bifunctional activities and strong durability for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in alkaline solution. The value of ΔE (bifunctional performance parameter) for Co2P@CoNPG-900 is only 0.92V. Compared to the noble metal-based catalysts, Co2P@CoNPG-900 has the obvious advantages in durability and bifunctional activities. The integration of Co2P and multielement co-doped graphene into a hybrid material is a new and promising strategy to design bifunctional oxygen electrode catalysts for renewable energy technologies.