在六角氧化电极中的质子插入机制的洞察
Heng Jiang1, Jessica J Hong1, Xianyong Wu1
1Department of Chemistry , Oregon State University , Corvallis , Oregon 97331-4003 , United States.
Journal of the American Chemical Society
|September 6, 2018
概括
六角氧化水合物 (WO3·0.6H2O) 电极包含网状水,并经过三阶段的质子插入过程. 这种材料具有出色的循环寿命和有前途的电化学性能.
科学领域:
- 电化学
- 材料科学
- 无机化学
背景情况:
- 六角氧化水合物 (WO3·0.6H2O) 是用于储能应用的有前途的电极材料.
- 了解离子运输和结构演变对于优化其性能至关重要.
研究的目的:
- 在WO3·0.6H2O中研究质子插入和提取过程中的格子水的行为.
- 为了阐明质子插入的多阶段机制.
- 将结构变化与电化学循环相关联.
主要方法:
- 使用电化学石英晶体微平衡 (EQCM) 来监测循环过程中的质量变化.
- 使用现场X射线衍射 (XRD) 来分析结构变化.
- 进行电化学循环测试以评估性能和稳定性.
主要成果:
- 在浸泡和初始循环过程中,WO3·0.6H2O吸收了格子水.
- 质子插入发生在三个不同的阶段,包括网状水驱逐,裸体质子插入和离子插入.
- 质子化会诱导异型结构变化,包括c轴收缩和ab平面膨胀.
- 该材料具有很长的循环寿命 (>20,000个循环),具有良好的容量和速率能力.
结论:
- 这项研究揭示了晶格水和WO3·0.6H2O中的质子传输之间的复杂相互作用.
- 观察到的结构动态是材料电化学稳定性和性能的关键.
- WO3·0.6H2O是一种强大的电极材料,具有显著的电化学能量储存潜力.
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