Abstract:
Achieving dynamic and reversible control over electrocatalytic reactions underpins the chemistry of next-generation energy devices. This work reveals a unique mechanism, atom-scale charge reorganization within a deliberately engineered metal-organic framework (MOF), that enables electrocatalytic switching during dioxygen redox processes. By precisely modulating atomic-level electronic structures, oxidation states and localized charge distributions through interfaces with nitrogen-rich supports, this work realizes a switchable bifunctional catalytic pathway that lowers the oxygen evolution (OER) and reduction (ORR) voltage gap to an exceptionally low 0.77 V. Notably, this modulation facilitates a mechanistic transition from a two- to a four-electron pathway during ORR, significantly enhancing reaction efficiency. This charge-driven reorganization mechanism translates into a high-performance rechargeable air battery, delivering superior power density, cycling stability, and energy efficiency over 100 h of continuous operation, surpassing noble metal-based systems. This work introduces localized charge reorganization as a powerful design principle for reconfigurable and high-efficiency MOF-based electrocatalysts in next-generation energy devices.