Interfacial-polarization-driven charge dynamics enables >6000-hour stability in oxide-based rechargeable metal-air batteries

Abstract

Durability remains the central bottleneck in oxygen electrocatalysts and metal-air batteries, where structural degradation and interfacial instability limit lifetime. Here we report a bifunctional oxygen catalyst that achieves unprecedented stability, over 6240 h (≈18,720) cycles, in a rechargeable Zn-air battery using a purely metal-oxide framework. The catalyst integrates electrochemically dispersed AgMn single-atom-alloy (SAA) sites with a Ni-metal-coated NiO@YFeO3 perovskite core-shell, forming a triply coupled architecture that generates a built-in-interfacial field and drives bidirectional charge redistribution. The YFeO3 core provides Fe3+/Fe2+ redox buffering, the NiO shell undergoes adaptive reconstruction during oxygen evolution, and the atomic-layer-deposited Ni layer ensures continuous conductivity and interfacial cohesion. At the surface, AgMn SAA sites induce localized polarization through Mn↔Ni charge transfer and Ag-assisted charge stabilization, tuning oxygen-intermediate energetics and mitigating structural fatigue. Consequently, the catalyst exhibits an oxygen-evolution overpotential of 140 mV at 10 mAcm-2 and oxygen-reduction half-wave potential of 0.86 V (∆E = 0.51 V), surpassing Pt/C and RuO2 benchmarks. In Zn-air batteries, it delivers 356.4 mW cm-2 peak power and 1047 Wh kg-1 energy density. Operando vibrational spectroscopy confirms reversible OOH intermediates and sustained surface reconstruction, while in situ grazing-incidence wide-angle X-ray scattering verifies reversible Zn0/Zn2+ transitions and dendrite suppression.