Mn-based layered oxides exhibit high theoretical capacity and are environmentally friendly. However, the Mn²⁺ dissolution and structural degradation during the cycling process result in performance decay. Herein, interface engineering using an artificial Al₂O₃ coating layer was proposed to improve the performance of the K_0.5MnO₂ material. This Al₂O₃ protective layer acts as a barrier to avoid direct contact between the active material and the electrolyte, which could improve the Coulombic efficiency by inhibiting the side reactions, and boost the cycling stability via suppressing the Mn²⁺ dissolution. In addition, the Al₂O₃ coating layer modified K_0.5MnO₂ electrode exhibits highly reversible structure evolution, which could be attributed to the mitigation of structural degradation. As a result, the K_0.5MnO₂@Al₂O₃ cathode delivers a high capacity (95.3 mAh g^‒1 at 50 mA g^‒1) and long lifespan (53% capacity over 300 cycles).

锰基层状氧化物表现出高理论容量并且对环境友好。然而，循环过程中Mn ^{2+溶解和结构退化导致性能下降。}_{在此，提出了使用人工Al 2} O ₃涂层的界面工程来提高K _0.5 MnO ₂材料的性能。该Al ₂ O ₃保护层充当屏障，避免活性材料与电解质直接接触，可通过抑制副反应提高库仑效率，并通过抑制Mn ²⁺溶解提高循环稳定性。此外，铝₂ O ₃涂层改性的K _0.5 MnO ₂电极表现出高度可逆的结构演变，这可归因于结构退化的缓解。因此，K _0.5 MnO ₂ @Al ₂ O ₃阴极具有高容量（95.3 mAh g ^-1在 50 mA g ^-1时）和长寿命（53% 的容量超过 300 个循环）。