Sodium‐ion batteries (SIBs) using transition‐metal oxides as cathodes have been considered as prospective alternatives for energy storage applications. Herein, the 4d‐cation Zr‐substitution strategy is proposed to optimize the structure and electrochemical properties of Na_0.44MnO₂ for the first time. In situ X‐ray diffraction demonstrates that the optimized Na_0.44Mn_0.98Zr_0.02O₂ exhibits a smaller volume change (only 4.25 %) during the initial charge/discharge process. Additionally, the Na⁺ diffusion coefficients are significantly enhanced after Zr introduction, thus leading to superb rate properties. A high reversible capacity of 112 mAh g⁻¹ can be obtained at 1 C. The long cycle lifespan can be supported by 78 mAh g⁻¹ that is maintained after 1000 cycles with a capacity retention of 80 % at 5 C. These findings not only indicate that 4d‐cation Zr‐substitution is an effective approach to tune the tunnel‐type cathodes, but also provide a new avenue to devise and optimize high‐performance cathodes for SIBs.

中文翻译：

---

设计采用4 d阳离子Zr掺杂的氧化钠锰作为钠离子电池的高性能阴极

使用过渡金属氧化物作为阴极的钠离子电池（SIB）被认为是储能应用的潜在替代品。本文首次提出了4d阳离子Zr取代策略，以优化Na _0.44 MnO ₂的结构和电化学性能。原位X射线衍射表明，优化的Na _0.44 Mn _0.98 Zr _0.02 O ₂在初始充电/放电过程中表现出较小的体积变化（仅4.25％）。另外，引入Zr后，Na ⁺扩散系数显着提高，从而导致极好的速率特性。112 mAh g ^-1的高可逆容量可以在1 C下获得。78 mAh g ^-1可以支持较长的循环寿命，在1000次循环后可以维持该状态，在5 C下可以保持80％的容量。这些发现不仅表明4d阳离子Zr取代是调整隧道型阴极的有效方法，但也为设计和优化SIB的高性能阴极提供了新途径。