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在VO2上合理调节最佳氧空度,用于高级水性离子电池阴极
Chen Zhang1, Zhi-Hai Wu1, Ci-Qing Yang2
1Laboratory of Chemical Engineering Thermodynamics, Department of Chemical Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
ACS applied materials & interfaces
|July 28, 2024
概括
在碳纳米纤维上的VO2中控制的氧空缺可以提高水性离子电池的性能. 这种缺陷工程提高了先进电池材料的能量存储能力和稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 二氧化 (VO2) 是水性离子电池 (ZIB) 的一个有前途的阴极材料,因为它的结构和容量.
- 挑战包括缓慢的动力学和由强的Zn2+相互作用引起的结构不稳定性.
- 缺陷工程,特别是氧气空缺,可以增强离子电子动态和稳定性,但精确的控制是困难的.
研究的目的:
- 开发一种方法来精确控制ZIB的VO2阴极材料中的氧气空缺.
- 提高基于VO2的电极的电化学性能和结构稳定性.
- 为了优化Zn2+在VO2结构中的吸附和迁移能量.
主要方法:
- 在一阶段的热水过程中,在碳纳米纤维 (CNF) 上用受控的氧空位制备VO2,形成Ov-VO2@CNF.
- 为Zn2+离子平衡吸附和迁移能量障碍.
- 用于ZIBs的Ov-VO2@CNF电极的电化学表征.
主要成果:
- Ov-VO2@CNF电极表现出高特异容量,在0.1 A g-1下超过450 mAh g-1.
- 在2000个循环后,在5A g-1下达到318 mAh g-1的优异循环稳定性 (85%的保留率).
- 该方法有效地平衡了Zn2+吸附和迁移能量.
结论:
- 在VO2@CNF中精确调节氧空缺的缺陷工程是先进的ZIB阴极材料的可行策略.
- 开发的热方法提供了一种简单而有效的途径来提高电池性能.
- 这项工作为优化高性能水性离子电池的电极材料提供了洞察力.
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