Enhancing Zn<sup>2+</sup>/H<sup>+</sup> Joint Charge\nStorage in MnO<sub>2</sub>: Concurrently Tailoring Mn’s Local\nElectron Density and O’s p‑Band Center

Enhancing proton storage in the zinc-ion battery cathode\nmaterial\nof MnO<sub>2</sub> holds promise in promoting its electrochemical\nperformance by mitigating the intense Coulombic interaction between\ndivalent zinc ions and the host structure. However, challenges persist\nin addressing the structural instability caused by Jahn–Teller\neffects and accurately modulating H<sup>+</sup> intercalation in MnO<sub>2</sub>. Herein, the doping of high-electronegativity Sb with fully\noccupied d-orbital in MnO<sub>2</sub> is reported. The Sb doping strategy\nengenders the formation of Mn–O–Sb path in the structure\nwith a strong dipole polarization field, which facilitates the delocalization\nof e<sub>g</sub> orbital electron in Mn and thus mitigates the Jahn–Teller\neffects. Simultaneously, adjusting the level of Sb doping in MnO<sub>2</sub> leads to modulation of the p-band center of O, optimizing\nits interaction with hydrogen and thereby enhancing proton storage.\nConsequently, MnO<sub>2</sub> doped with 6% Sb exhibits commendable\nperformance in both rate capability and cycling endurance, delivering\n113 mAh g<sup>–1</sup> at 2 A g<sup>–1</sup> after 2000\ncycles. This investigation underscores the crucial role of electronic\nstructural engineering in elevating the electrochemical performance\nof cathode materials for zinc-ion batteries.