Ni-Fe/Co-Fe Oxide-MoSe 2 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 (NiFe 2 O 4 and CoFe 2 O 4 ) and their hybrid nanostructures with MoSe 2 as potential electrocatalysts for electrically rechargeable Zn-air batteries. The NiFe 2 O 4 -MoSe 2 hybrid nanostructure exhibits the best electrocatalytic activity (overpotential η 10 ≈ 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 NiFe 2 O 4 -MoSe 2 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 g Zn -1 , and an energy density of ∼1205 Wh kg Zn -1 . The superior performance of the hybrid nanostructures is due to the synergistic effect between MoSe 2 and bimetal oxides, which enhances the conductivity, oxygen mobility, and active sites of the catalysts.