N-Doped C Concatenates FeCo Alloys and Co Nanoparticles as a Dual-Functional Oxygen Catalyst for Long-Lasting Zinc–Air Batteries

Cathode electrocatalysts with rich active sites are indispensable for achieving the superior performance of zinc–air batteries (ZABs). However, the integration of both oxygen reduction reaction and oxygen evolution reaction (ORR and OER) catalytic active sites poses challenges due to their opposite catalytic mechanisms. Besides, a mass of highly oxidizing intermediates generated by the OER site would attack the adjacent ORR active sites. Herein, a bottom-up strategy is developed to catenate the Co and FeCo beads onto the needle carbon connexons, wherein the FeCo alloys undergo self-reconstruction into FeOOH and Co(OH) 2 to facilitate the OER, while the separated Co nanoparticles play a crucial role in promoting the ORR. The FeCo AL &Co NP /NC Janus material exhibits significant potential in stabilizing its bifunctional oxygen electrocatalytic properties, bestowing rechargeable ZABs with long cycling stability (752 h) as the air–cathode catalyst. This study paves a pathway for the precise manipulation of the distribution of distinct active sites and selective control over oxygen electrocatalysts.