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 gZn–1 (close to theoretical value of 820 mAh gZn–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.