FeNi Confined in N-Doped Carbon as a Highly Efficient Bi-Functional Catalyst for Rechargeable Zn–Air Batteries

Rechargeable zinc–air batteries (RZABs) are basically dependent on both affordable and long-lasting bifunctional electrocatalysts. A non-precious metal catalyst, a FeNi nanoalloy catalyst (FeNi@NC) with an extremely low metal consumption (0.06 mmol), has been successfully synthesized. It shows a high half-wave potential of 0.845 V vs. RHE for ORR and a low overpotential of 318 mV for OER at 10 mA cm−2, favoring a maximum power density of 116 mW cm−2 for the constructed RZABs. The voltage plateau is reserved even after 167 h of cell operation. The synergistic effect between the nano-sized FeNi alloy and nitrogen-doped carbon with abundant N sites mainly contributes to the electrocatalytic activity. This research can provide some useful guidelines for the development of economic and efficient bifunctional catalysts for RZABs.