Manganese dioxide is a typical electrode material for supercapacitor due to its high theoretical capacitance and good environmental compatibility. However, the development of MnO₂ as electrode is limited by inferior conductivity, sluggish ionic transfer kinetics and poor cycling stability. Herein, we present a structure distortion strategy via Ni doping in MnO₂ to boost its Na⁺ storage performance. The as-obtained Ni-MnO₂ can deliver a high specific capacity of 379 F g^-1 at 1 A g^-1, excellent rate performance of 281 F g^-1 at 20 A g^-1, and a significantly enhanced cycling stability. In situ Raman results verify that Ni-MnO₂ with structure distortion can achieve a promising cycling life. Density functional theory results suggest that the structure distortion can efficiently modulate electron configuration by delocalizing electron. Furthermore, the Na⁺ diffusion energy barrier is remarkedly decreased in Ni-MnO₂, thus accelerating ionic transport kinetics. An asymmetric supercapacitor based on Ni-MnO₂ cathode exhibits a high energy density of 114.6 Wh kg^-1 at a power density of 3600 W kg^-1. This work verifies the efficiency of structure distortion strategy on the improvement of Na ion storage performance in MnO₂, which can be extended for the optimization of other electrode materials for energy storage.

二氧化锰具有较高的理论电容和良好的环境相容性，是一种典型的超级电容器电极材料。然而，MnO ₂作为电极的发展受到电导率差、离子转移动力学缓慢和循环稳定性差的限制。在此，我们提出了一种通过在 MnO _{2 中}掺杂 Ni来提高其 Na ⁺存储性能的结构畸变策略。所获得的Ni-MnO ₂可以在1 A g ^-1下提供379 F g ^-1的高比容量，在20 A g ^{-1 下}具有281 F g ^{-1 的}优异倍率性能，并且显着增强了循环稳定性。原位拉曼结果证实 Ni-MnO₂具有结构畸变可以实现有希望的循环寿命。密度泛函理论结果表明，结构畸变可以通过离域电子有效地调节电子构型。此外，Ni-MnO _{2 中}的Na ⁺扩散能垒显着降低，从而加速离子传输动力学。基于Ni-MnO ₂阴极的不对称超级电容器在3600 W kg ^-1的功率密度下表现出114.6 Wh kg ^-1的高能量密度。该工作验证了结构畸变策略对提高MnO ₂中Na离子存储性能的效率，可扩展用于优化其他用于储能的电极材料。