Catalyst–Support Interaction in Polyaniline-Supported Ni3Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn-Air Batteries.

Highlights: Ni₃Fe oxide, with an average size of 3.5 ± 1.5 nm, was successfully deposited onto polyaniline (PANI) support through a solvothermal strategy followed by calcination. The catalyst–support interaction between Ni₃Fe oxide and PANI can enhance the Ni-O covalency via the interfacial Ni-N bond. Ni₃Fe oxide/PANI-assembled Zn-air batteries achieve superior cycling life for over 400 h at 10 mA cm⁻² and a low charge potential of around 1.95 V. Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction (OER). Here we modulate the catalyst–support interaction in polyaniline-supported Ni₃Fe oxide (Ni₃Fe oxide/PANI) with a robust hetero-interface, which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm⁻² and specific activity of 2.08 mA cm_ECSA⁻² at overpotential of 300 mV, 3.84-fold that of Ni₃Fe oxide. It is revealed that the catalyst–support interaction between Ni₃Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond, thus promoting the charge and mass transfer on Ni₃Fe oxide. Considering the excellent activity and stability, rechargeable Zn-air batteries with optimum Ni₃Fe oxide/PANI are assembled, delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm⁻². The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. [ABSTRACT FROM AUTHOR]