Honeycomb-like carbon with doping of a transition-metal and nitrogen for highly efficient zinc–air battery and zinc-ion battery

Abstract

The aqueous zinc-based batteries such as the Zn–air battery and the Zn-ion battery, featured with low-cost, high safety, high specific capacity and environmental-friendliness, have attracted intensive interest for their energy storage capability. For high performance zinc-based batteries, electrocatalysts with good conductivity, convenient mass transfer path and adequate accessible active sites are required. Herein, the fabrication of transition-metal/nitrogen co-doped honeycomb-like carbon materials with a hierarchical porous structure using a freeze-drying and one-step pyrolysis method is described. The as-prepared FeZnN–C is used as the cathode material of the zinc–air battery, which displays a high peak power density of 257 mW cm⁻², a superior discharging voltage platform of about 1.36 V and a large specific capacity of 785 mA h g_Zn⁻¹. The prepared Zn/ZnN–C was used as the anode of a Zn-ion battery which exhibits great cycle stability and a high charging/discharge rate. This work provides a novel and simple method for the construction of highly efficient electrocatalysts with hierarchical macro–meso–micro-porous structure and multi-active sites, which could be used for potential applications involving aqueous zinc-based batteries.