Exploiting encapsulated FeCo alloy decorated N-doped hierarchically porous carbon electrocatalysts in rechargeable Zn-air batteries

Abstract Exploiting highly active non-noble metal catalyst with designed nanoarchitecture is essential and formidable for the rechargeable Zn-air batteries (ZABs). To this end, hierarchically porous N-doped carbon hybrids with encapsulated FeCo alloy (FeCo@NC) is designed by template-assisted method. The optimized sample pyrolyzed at 800 oC (FeCo@NC800) possesses a large specific surface area of 1195 m2 g-1, plentiful micro-/meso-/macro-pores and is rich in defects and graphitic N-doped carbon atoms. These preeminent characteristics endow the catalyst with superior bifunctional oxygen electrocatalytic activities (ΔE=E10-E1/2=852 mV) in alkaline electrolyte, as well as outstanding stability. As air-electrode catalyst in ZAB, FeCo@NC800 reveals high power density of 169 mW cm-2, excellent rechargeable property and cycling stability. Moreover, the as-obtained catalyst displays promising application potentiality in solid-state ZAB.