阴离子介导的溶解结构和水性离子电解质的间隙化学
Shiqiang Wei1, Quan Zhou1, Shuangming Chen1
1National Synchrotron Radiation Laboratory, State Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230029, P. R. China.
概括
水性离子电解质中的离子协调决定了电极性能. 不同的盐导致不同的协调结构,影响先进电池设计的可逆性和稳定性.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
背景情况:
- 设计高性能电解质需要了解溶剂/溶解物协调结构及其对电极间隙的影响.
- 水性离子电解质中的离子协调机制尚未得到充分研究,这限制了合理的电解质设计.
研究的目的:
- 系统地阐明Zn2+协调环境在含有不同盐的水性离子电解质中.
- 调查离子协调对电极间隔化学和电化学性质的影响.
主要方法:
- 射线吸收细结构 (XAFS) 光谱学.
- 超动力学模拟的模拟.
- 基于同步光子的光谱学.
- 在现场同步子辐射X射线衍射 (SRXRD)
主要成果:
- 确定了不同的Zn2+协调物种:[Zn(H2O) 6[2+ (Zn(OTf) 2),[Zn(H2O) 5Cl]+ (ZnCl2),以及[Zn(H2O) 4Ac]<>+ (Zn(Ac) 2).
- 电解质显示了最小的电极晶格扭曲和可逆循环.
- 电解质ZnCl2和Zn(Ac)2由于电极溶解和酸盐共插入,分别表现出结构形状的变化,影响了可逆性.
结论:
- 阳离子协调化学极大地影响水性离子电池中的电极间隔行为.
- 电极溶解和阳离子联合插入显著降低了电化学可逆性.
- 通过控制溶解结构,研究结果为开发高性能水性电池提供了指导.
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