Liu Weicai, Zong Hui, Li Mengshu, Zeng Ziquan, Gong Shijing, Yu Ke, Zhu Ziqiang
Key Laboratory of Polar Materials and Devices (MOE), Department of Electronics, East China Normal University, Shanghai 200241, China.
Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China.
ACS Appl Mater Interfaces. 2023 Mar 15;15(10):13554-13564. doi: 10.1021/acsami.2c23314. Epub 2023 Mar 6.
A twodimensional MXene (TaC) was innovatively used herein to modulate the space group and electronic properties of vanadium oxides, and the MXene/metal-organic framework (MOF) derivative VO(B)@TaC with 3D network crosslinking was prepared, which was then employed as a cathode to improve the performance of aqueous zinc ion batteries (ZIBs). A novel method combining HCl/LiF and hydrothermal treatments was used to etch TaAlC to obtain a large amount of accordion-like TaC, and the V-MOF was then hydrothermally grown on the surface of the stripped TaC MXene. During the annealing process of V-MOF@TaC, the addition of TaC MXene liberates the V-MOF from agglomerative stacking, allowing it to show additional active sites. More significantly, TaC prevents the V-MOF in the composite structure from converting into VO of space group but into VO(B) of space group 2/ after annealing. A considerable advantage of VO(B) for Zn intercalation is provided by the negligible structural transformation during the intercalation process and the special tunnel transport channels, which have an enormous area (0.82 nm along the axis). According to first-principles calculations, there is a strong interfacial interaction between VO(B) and TaC, which deliver remarkable electrochemical activity and kinetic performances for the storage of Zn. Therefore, the ZIBs prepared with the VO(B)@TaC cathode material exhibit an ultra-high capacity of 437 mA h·g at 0.1 A·g while showing good cycle performance and dynamic performance. This study will offer a fresh approach and a reference for creating metal oxide/MXene composite structures.
本文创新性地使用二维MXene（TaC）来调节钒氧化物的空间群和电子性质，并制备了具有三维网络交联结构的MXene/金属有机框架（MOF）衍生物VO(B)@TaC，随后将其用作阴极以提高水系锌离子电池（ZIBs）的性能。采用一种结合HCl/LiF和水热处理的新方法蚀刻TaAlC以获得大量手风琴状TaC，然后在剥离的TaC MXene表面水热生长V-MOF。在V-MOF@TaC的退火过程中，添加TaC MXene使V-MOF从团聚堆积中释放出来，使其显示出额外的活性位点。更重要的是，TaC可防止复合结构中的V-MOF在退火后转变为空间群 的VO，而是转变为空间群2/ 的VO(B)。VO(B)在锌嵌入方面的一个显著优势是嵌入过程中结构转变可忽略不计，以及具有特殊的隧道传输通道，其沿 轴方向的面积巨大（0.82 nm）。根据第一性原理计算，VO(B)与TaC之间存在强烈的界面相互作用，这为锌的存储提供了卓越的电化学活性和动力学性能。因此，用VO(B)@TaC阴极材料制备的ZIBs在0.1 A·g时表现出437 mA h·g的超高容量，同时具有良好的循环性能和动力学性能。本研究将为创建金属氧化物/MXene复合结构提供一种新方法和参考。
