Layered transition metal oxides are highly promising host materials for K ions, owing to their high theoretical capacities and appropriate operational potentials. To address the intrinsic issues of KxMnO2 cathodes and optimize their electrochemical properties, a novel P3‐type oxide doped with carefully chosen cost‐effective, electrochemically active and multi‐functional elements is proposed, namely K0.57Cu0.1Fe0.1Mn0.8O2. Compared to the pristine K0.56MnO2, its reversible specific is increased from 104 to 135 mAh g‐1. In addition, the Cu and Fe co‐doping triples the capacity under high current densities, and contributes to long‐term stability over 500 cycles with a capacity retention of 68%. Such endeavor holds the potential to make potassium‐ion batteries particularly competitive for application in sustainable, low‐cost, and large‐scale energy storage devices. In addition, the cathode is also extended for sodium storage. Facilitated by the interlayer K ions that protect the layered structure from collapsing and expand the diffusion pathway for sodium ions, the cathode shows a high reversible capacity of 144 mAh g‐1, fast kinetics and a long lifespan over 1000 cycles. The findings offer a novel pathway for the development of high‐performance and cost‐effective sodium‐ion batteries.

中文翻译：

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选择性晶格掺杂可实现低成本、高容量和持久的钾层状氧化物阴极，用于钾和钠的存储

层状过渡金属氧化物由于其高理论容量和适当的操作潜力，是非常有前途的钾离子主体材料。为了解决 KxMnO2 阴极的固有问题并优化其电化学性能，提出了一种掺杂有精心选择的经济高效、电化学活性和多功能元素的新型 P3 型氧化物，即 K0.57Cu0.1Fe0.1Mn0.8O2。与原始的 K0.56MnO2 相比，其可逆比从 104 mAh g-1 增加到 135 mAh g-1。此外，Cu和Fe共掺杂使高电流密度下的容量增加了三倍，并有助于超过500次循环的长期稳定性，容量保持率为68%。这种努力有可能使钾离子电池在可持续、低成本和大规模储能设备中的应用中特别具有竞争力。此外，阴极还被扩展用于钠存储。在层间 K 离子的促进下，保护层状结构免于塌陷并扩大钠离子的扩散路径，阴极表现出 144 mAh g-1 的高可逆容量、快速动力学和超过 1000 次循环的长寿命。这些发现为开发高性能且具有成本效益的钠离子电池提供了一条新途径。