High-density iron nanoparticles encapsulated within nitrogen-doped carbon nanoshell as efficient oxygen electrocatalyst for zinc–air battery

Abstract Exploring highly efficient electrocatalysts toward oxygen reduction and evolution reactions are critical for the development of rechargeable zinc–air batteries. As a novel class of electrocatalyst, transition metal nanoparticles encapsulated within nitrogen-doped carbon have been regarded as competitive alternative to replace noble metal electrocatalysts. Herein, we report successful synthesis of high-density iron nanoparticles encapsulated within nitrogen-doped carbon nanoshell (Fe@N–C) by solid-phase precursor׳s pyrolysis of dicyandiamide and ammonium ferric citrate. The resulting Fe@N–C material shows excellent bifunctionality for ORR and OER in alkaline medium compared to state-of-the-art commercial Pt/C and IrO2, which demonstrates high performance and cycling durability in zinc–air battery as efficient oxygen electrocatalyst.