电化学双层电容器的实时NMR研究
Hao Wang1, Thomas K-J Köster, Nicole M Trease
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
Journal of the American Chemical Society
|November 3, 2011
概括
-11核磁共振光谱学揭示了四甲酸 (BF4-) 离子在多孔碳上具有明显的结合点. 在现场NMR观察到超级电容器的实时离子迁移和结合变化.
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
- 频谱学是一种光谱学.
背景情况:
- 超级电容器使用电化学双层电容器来储存能量.
- 了解电极材料上的离子吸附对于超级电容器性能至关重要.
- 具有高表面积的多孔碳是有前途的电极材料.
研究的目的:
- 用NMR光谱学研究四甲酸 (BF4-) 离子在多孔碳上的吸附行为.
- 为了确定碳表面上BF4-离子的不同结合点.
- 在超级电容器运行期间,在现场监测离子迁移和结合变化.
主要方法:
- (11) B核磁共振 (11B NMR) 光谱学.
- 在电化学循环过程中的现场NMR测量.
- 对高度多孔,高表面积的碳材料进行吸附研究.
主要成果:
- 确定碳表面上BF4-离子的独特结合点.
- 在电极表面之间实时观察BF4-离子的迁移.
- 在操作过程中检测离子与碳表面结合的性质的动态变化.
结论:
- (11) B NMR 光谱对于阐明超级电容器中的离子吸附机制是有效的.
- 该研究提供了关于BF4-离子在多孔碳电极中的动态行为的见解.
- 了解这些动态可以指导改进的超级电容材料和电解质的设计.
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