A ZIF-derived hierarchically porous Fe–Zn–N–C catalyst synthesized <i>via</i> a two-stage pyrolysis for the highly efficient oxygen reduction reaction in both acidic and alkaline media

Abstract

A ZIF-derived Fe-Zn-N-C catalyst with sufficient exposure of bimetallic active sites and well-balanced micro/mesopores is synthesized by a two-stage pyrolysis process and exhibits superior oxygen reduction activity with high half-wave potentials of up to 0.819 V in 0.1 M HClO₄ and 0.918 V in 0.1 M KOH.