Wang Lipeng, Cao Ziyi, Zhuang Peiyuan, Li Jiaxin, Chu Hang, Ye Zhuolin, Xu Dongxiao, Zhang Hong, Shen Jianfeng, Ye Mingxin
Institute of Special Materials and Technology, Fudan University, Shanghai 200433, P. R. China.
Department of Chemistry, Fudan University, Shanghai 200438, China.
ACS Appl Mater Interfaces. 2021 Mar 24;13(11):13338-13346. doi: 10.1021/acsami.1c01405. Epub 2021 Mar 9.
Manganese-based compounds have emerged as attractive cathode materials for zinc-ion batteries owing to their high operating voltage, large specific capacity, and no pollution. However, the structural collapse and sluggish kinetics of manganese-based compounds are major obstacles that hinder their practical applications. Here, a kind of novel layered CaMnO with a low ion diffusion barrier and high structural stability has been achieved through an electrochemical charging process with in situ injecting oxygen vacancies. This greatly increases the electrochemical active area and improves the Zn ions diffusion coefficient by 2 orders of magnitude, which significantly enhances the reaction kinetics, pseudocapacitance properties, and capacity. As a result, the cathode containing oxygen vacancies present an impressive reversible capacity of 368 mAh g, an unprecedented energy density of 512 Wh kg, and superior capacity retention of 92.3% at a high current density of 5 A g after 3000 cycles. This work unveils an effective method for vacancy regulation of electrode materials, paving a new way to improve the electrochemical performance of zinc-ion batteries.
由于具有高工作电压、大比容量且无污染，锰基化合物已成为锌离子电池颇具吸引力的阴极材料。然而，锰基化合物的结构坍塌和缓慢的动力学是阻碍其实际应用的主要障碍。在此，通过原位注入氧空位的电化学充电过程，实现了一种具有低离子扩散势垒和高结构稳定性的新型层状CaMnO。这极大地增加了电化学活性面积，并将锌离子扩散系数提高了2个数量级，显著增强了反应动力学、赝电容性能和容量。结果，含有氧空位的阴极在3000次循环后，在5 A g的高电流密度下呈现出令人印象深刻的368 mAh g可逆容量、512 Wh kg的前所未有的能量密度以及92.3%的优异容量保持率。这项工作揭示了一种电极材料空位调控的有效方法，为提高锌离子电池的电化学性能开辟了一条新途径。
