FeCo 5 /Nitrogen doped carbon as an efficient bifunctional oxygen electrocatalyst for Zn-Air batteries

Bifunctional non-precious metal catalysts (NPMCs) are crucial for accelerating the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at cathode of zinc -air batteries (ZABs). In this work, we report bimetallic FeCo x /nitrogen doped carbon (NC) catalysts synthesized through a metal-organic frameworks (MOFs) confinement strategy to ensure uniform dispersion of Fe and Co, followed by high-temperature pyrolysis. The prepared FeCo x /nitrogen doped carbon catalyst is rich in Fe-N x and Co-N x active sites and exhibits excellent electrocatalytic activities towards ORR and OER in alkaline electrolyte. Among compositions studied, FeCo x / nitrogen doped carbon catalyst demonstrates a high half-wave potential ( E 1/2 ) of 0.908 V, an overpotential of 440 mV at E j=10 , and a low potential difference ( Delta E ) between E j=10 and E 1/2 of only 0.762 V. After a 10 h chronoamperometry (CA) test at an applied voltage of 0.5 V, the catalyst retains 91 % of its initial activity. The synthesized catalyst also shows practical utility when used as cathodic catalysts in ZABs, exhibiting a high peak power density of 155.7 mW cm -2 , a excellent discharge specific capacity of 715.1 mAh g -1 and long cycle stability for 188 h.