Two-Dimensional Hierarchical Fe–N–C Electrocatalyst for Zn-Air Batteries with Ultrahigh Specific Capacity

Promoting the performance of Zn-air batteries urgently requires rational design of electrocatalysts with highly efficient mass and charge transfer capacity. In this study, two-dimensional (2D) hierarchical Fe–N–C materials were developed as highly active oxygen reduction reaction (ORR) catalysts. Benefiting from the enhanced mesoporosity and two orders of magnitude higher electrical conductivity, the as-obtained catalysts unify efficient mass transport and expedite charge transfer. Therefore, Zn-air battery integrated with this catalyst achieves an ultrahigh specific capacity of 798 mAh g Zn –1 (close to theoretical value of 820 mAh g Zn –1 ) and excellent durability for over 130 h. Our work paves a new way to engineer the transfer capacity of triple-phase boundary to boost the performance of metal-air battery.