School of Materials Science and Engineering, Changsha University of Science and Technology, Changsha 410114, Hunan, China.
School of Materials Science and Engineering, Changsha University of Science and Technology, Changsha 410114, Hunan, China.
J Colloid Interface Sci. 2023 Jun;639:124-132. doi: 10.1016/j.jcis.2023.02.057. Epub 2023 Feb 14.
Advances in cathode material design and understanding of intercalation mechanisms are necessary to improve the overall performance of aluminum ion batteries. Therefore, we designed ZnSe/SnSe hollow microcubes with heterojunction structure as a cathode material for aluminum ion batteries. ZnSe/SnSe hollow microcubes with an average size of about1.4 µm were prepared by selenization of ZnSn(OH) microcubes successfully. The shell thickness of ZnSe/SnSe hollow microcubes is about 250 nm. On one hand, the hollow cubic structure can effectively alleviate the volume effect, provide shorter ion diffusion paths, and increase the contact area with the electrolyte. On the other hand, ZnSe/SnSe heterojunction structure can establish a built-in electric field to facilitate ion transport. The synergistic effect of the two leads to the improved electrochemical performance of ZnSe/SnSe as the cathode of aluminum ion batteries. The material delivered a reversible capacity of 124 mAh/g after 150 cycles at a current density of 100 mA/g. Meanwhile, coulombic efficiency remained above 98% in almost all cycles. In addition, the electrochemical reaction mechanism and kinetic process of Al and ZnSe/SnSe were studied.
为了提高铝离子电池的整体性能，有必要在阴极材料设计和插层机制理解方面取得进展。因此，我们设计了具有异质结结构的 ZnSe/SnSe 空心微立方体作为铝离子电池的阴极材料。通过 ZnSn(OH)微立方体的硒化成功制备了平均尺寸约为 1.4µm 的 ZnSe/SnSe 空心微立方体。ZnSe/SnSe 空心微立方体的壳层厚度约为 250nm。一方面，空心立方结构可以有效缓解体积效应，提供更短的离子扩散路径，并增加与电解质的接触面积。另一方面，ZnSe/SnSe 异质结结构可以建立内置电场，有利于离子传输。这两种效应的协同作用导致 ZnSe/SnSe 作为铝离子电池阴极的电化学性能得到改善。该材料在 100mA/g 的电流密度下循环 150 次后，可逆容量达到 124mAh/g。同时，在几乎所有循环中库仑效率都保持在 98%以上。此外，还研究了 Al 和 ZnSe/SnSe 的电化学反应机制和动力学过程。
