Quenching-induced Surface Reconstruction of Perovskite Oxides Activating Bifunctional Sites towards Oxygen Electrodes for Recharge Zinc–Air Batteries

Abstract

Exploring effective and dependable bifunctional oxygen electrode catalysts remains a persistent challenge for impeding the advancement of zinc-air batteries (ZABs). Herein, we propose an innovative solution quenching strategy to engineer a self-adaptive perovskite oxide/hydroxide heterojunction with dynamically reconfigurable active sites. Through deliberate Fe-ion doping and controlled oxygen defect engineering, this approach enables in situ surface reconstruction under operational conditions, effectively activating a lattice oxygen-mediated reaction pathway (LOM). The optimized quenched PrBaCo₂O_6-δ catalyst demonstrates exceptional bifunctionality with a remarkably reduced OER/ORR potential gap of 117 mV (ΔE = E_{OER@10mA/cm²} - E_ORR@E1/2), outperforming most reported perovskite analogs in alkaline media. When deployed in zinc-air batteries, the catalyst enables excellent cyclability with a record power conversion efficiency of 64.8% and maintains stability for 300 hours of cycling with a cycle efficiency decay rate of less than 7.3%. Our findings not only provide novel perspectives for designing self-optimizing electrocatalysts through defect-mediated phase engineering but also provide a paradigm for high-stability Zn-Air battery systems.