biostudies-literatureUnknown17(1)Duan YAqueous Ni-Zn microbatteries are safe, reliable and inexpensive but notoriously suffer from inadequate energy and power densities. Herein, we present a novel mechanism of superoxide-activated Ni substrate that realizes the redox reaction featuring three-electron transfers (Ni ↔ Ni³⁺). The superoxide activates the direct redox reaction between Ni substrate and KNiO₂ by lowering the reaction Gibbs free energy, supported by in-situ Raman and density functional theory simulations. The prepared chronopotentiostatic superoxidation-activated Ni (CPS-Ni) electrodes exhibit an ultrahigh capacity of 3.21 mAh cm^-2 at the current density of 5 mA cm^-2, nearly 8 times that of traditional one-electron processes electrodes. Even under the ultrahigh 200 mA cm<supNano-micro letters79https://www.ebi.ac.uk/biostudies/studies/S-EPMC11607291biostudies-literatureUltrahigh Energy and Power Density in Ni-Zn Aqueous Battery via Superoxide-Activated Three-Electron Transfer.PMC11607291Peng XYang KHo DLi BHe LGong ZDuan YfalseUltrahigh Energy and Power Density in Ni-Zn Aqueous Battery via Superoxide-Activated Three-Electron Transfer.Aqueous Ni-Zn microbatteries are safe, reliable and inexpensive but notoriously suffer from inadequate energy and power densities. Herein, we present a novel mechanism of superoxide-activated Ni substrate that realizes the redox reaction featuring three-electron transfers (Ni ↔ Ni³⁺). The superoxide activates the direct redox reaction between Ni substrate and KNiO₂ by lowering the reaction Gibbs free energy, supported by in-situ Raman and density functional theory simulations. The prepared chronopotentiostatic superoxidation-activated Ni (CPS-Ni) electrodes exhibit an ultrahigh capacity of 3.21 mAh cm^-2 at the current density of 5 mA cm^-2, nearly 8 times that of traditional one-electron processes electrodes. Even under the ultrahigh 200 mA cm<sup2024-01-01T00:00:00Z2024 Nov2026-03-17T16:15:19.045Z2025-04-07T02:59:29.459ZS-EPMC116072913961210910.1007/s40820-024-01586-z