Cobalt-carbon nanocage modified carbon foam as the efficient catalyst towards oxygen reduction reaction and high-performance zinc-air battery

Inspired by the space mud of artificial children's toy, a shape designable carbon foam (Co-NCF) is developed. This carbon foam is endowed with ferromagnetism, oil-absorption, lightweight and has a three-dimensional network intertwined with cobalt dots, nitride graphene and fibrous carbon. Those cobalt dots are actually encapsulated in a carbon nanocage, and then modified on the nitride graphene nanosheets. The Co-N bonds are generated at the core-shell interfaces of the cobalt-carbon nanocages. The network structure of carbon foam is beneficial to the mass and charge transfer of the electrocatalysis, and the cobalt-carbon nanocages further enhance the activity of oxygen reduction reaction (ORR). These advantages endow the as-prepared Co-NCF with the excellent ORR activity and outstanding catalytic stability that exceeding the commercial PVC catalyst. Applied as the electrocatalyst to the zinc-air battery, Co-NCF achieves good applicability with a high output power density and discharge capacity. This work provides a novel low-cost strategy for the development of material architectures and the high-performance ORR electrocatalysts.