Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
Shaanxi Key Laboratory of Nanomaterials and Nanotechnology, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
Adv Sci (Weinh). 2023 Mar;10(9):e2206836. doi: 10.1002/advs.202206836. Epub 2023 Jan 25.
Layered vanadium-based oxides are the promising cathode materials for aqueous zinc-ion batteries (AZIBs). Herein, an in situ electrochemical strategy that can effectively regulate the interlayer distance of layered NH V O quantitatively is proposed and a close relationship between the optimal performances with interlayer space is revealed. Specifically, via increasing the cutoff voltage from 1.4, 1.6 to 1.8 V, the interlayer space of NH V O can be well-controlled and enlarged to 10.21, 11.86, and 12.08 Å, respectively, much larger than the pristine one (9.5 Å). Among them, the cathode being charging to 1.6 V (NH V O -C1.6), demonstrates the best Zn storage performances including high capacity of 223 mA h g at 10 A g and long-term stability with capacity retention of 97.5% over 1000 cycles. Such superior performances can be attributed to a good balance among active redox sites, charge transfer kinetics, and crystal structure stability, enabled by careful control of the interlayer space. Moreover, NH V O -C1.6 delivers NH storage performances whose capacity reaches 296 mA h g at 0.1 A g and lifespan lasts over 3000 cycles at 5 A g . This study provides new insights into understand the limitation of interlayer space for ion storage in aqueous media and guides exploration of high-performance cathode materials.
层状钒基氧化物是有前途的水系锌离子电池（AZIBs）阴极材料。在此，提出了一种原位电化学策略，可以有效地定量调节层状 NH V O 的层间距，并揭示了最佳性能与层间距之间的密切关系。具体来说，通过将截止电压从 1.4、1.6 提高到 1.8 V，可以很好地控制和扩大 NH V O 的层间距，分别达到 10.21、11.86 和 12.08 Å，远大于原始层间距（9.5 Å）。其中，充电至 1.6 V 的阴极（NH V O -C1.6）表现出最佳的 Zn 存储性能，包括在 10 A g 时 223 mA h g 的高容量和 1000 次循环后容量保持率为 97.5%的长期稳定性。这种优异的性能归因于通过精心控制层间距，可以在活性氧化还原位点、电荷转移动力学和晶体结构稳定性之间实现良好的平衡。此外，NH V O -C1.6 还具有 NH 存储性能，在 0.1 A g 时的容量达到 296 mA h g，在 5 A g 时的寿命超过 3000 次循环。本研究为理解在水介质中离子存储的层间距限制提供了新的见解，并指导了高性能阴极材料的探索。
