Shengxue Yan, Hongyuan Liu, Xueqian Yuan, Shao‐hua Luo, Qing Wang, Yahui Zhang, Xin Liu, Jing Guo
To address challenges such as poor structural stability and short cycle life in potassium-ion battery cathodes, this study designed and synthesized a novel seven-component high-entropy oxide cathode material: K x Mn 7/13 Ni 1/13 Fe 1/13 Mg 1/13 Zn 1/13 Cu 1/13 Al 1/13 O 2 . A homogeneous solid solution with a single-phase rock-salt structure was successfully prepared via high-temperature solid-state synthesis, where the high-entropy effect significantly enhanced lattice stability. Electrochemical tests demonstrated that the material maintains over 81 % capacity retention after 100 cycles at 0.2 C. The synergistic effects of multiple transition metals effectively suppressed Jahn-Teller distortion and structural phase transitions, while Al 3+ and Mg 2+ doping reinforced framework stability. Additionally, Cu 2+ /Ni 2+ redox couples contributed to enhanced reversible capacity. This work confirms that the high-entropy strategy substantially improves structural integrity during K + (de)intercalation through lattice distortion and retarded diffusion effects, offering a new approach for developing long-cycle-life, high-stability potassium-ion battery cathodes.