Ni-Fe/Co-Fe Oxide-MoSe2 Hybrid Nanostructures as Novel Electrocatalysts for High-Performance Rechargeable Zinc-Air Batteries.

Metal-air batteries can play a crucial role in curbing air pollution due to carbon emission. Here, we report the hydrothermally synthesized bimetal oxides (NiFe2O4 and CoFe2O4) and their hybrid nanostructures with MoSe2 as potential electrocatalysts for electrically rechargeable Zn-air batteries. The NiFe2O4-MoSe2 hybrid nanostructure exhibits the best electrocatalytic activity (overpotential η10 ≈ 218 mV and Tafel slope ≈ 37 mV dec-1) for the OER study among prepared electrocatalysts in 1 M KOH electrolyte. Among the designed rechargeable Zn-air batteries, hybrid nanostructure-based batteries show superior performance, with the NiFe2O4-MoSe2 based device showing the best performance, having a high open-circuit voltage of ∼1.43 V, a peak power density of ∼176 mW cm-2, a specific capacity of ∼1025 mAh gZn-1, and an energy density of ∼1205 Wh kgZn-1. The superior performance of the hybrid nanostructures is due to the synergistic effect between MoSe2 and bimetal oxides, which enhances the conductivity, oxygen mobility, and active sites of the catalysts.