▎ 摘 要
Developing low cost and efficient electrocatalysts for oxygen reduction reaction (ORR) is largely beneficial for preparing regenerative zinc-air batteries. Herein, ultrasmall cobalt nanoparticles were uniformly embedded in N,S-codoped hierarchically graphene-like carbon nanostructures (Co@NSC) by a scalable facile pyrolysis method. Due to the hierarchical pore structures, high surface area, and synergistic effect between the dual-doped heteroatoms and transition metal, the resultant Co@NSC displayed high electrochemical activity. After H2SO4 treatment, the electrochemical performance of Co@NSC-acid enhanced with a positive half-wave potential (0.82 V vs RHE), high electron number (4e(-)), and a low HO2- yield. As a air cathode catalyst in the rechargeable zinc-air battery, the Co@NSC-acid showed a comparable open circuit voltage (1.42 V), remarkable peak power density (73.5 mW cm(-2)), and high charge-discharging cycling stability.