基于碳纳米管森林的电双层电容器的分子模拟
Lu Yang1, Brian H Fishbine, Albert Migliori
1Los Alamos National Laboratory, Los Alamos, New Mexico, New Mexico 87545, USA.
Journal of the American Chemical Society
|August 7, 2009
概括
分子模拟显示电双层电容器与碳纳米管森林实现容量约为80 F/g. 这种性能与实验数据一致,受孔径的大小的影响,为材料优化提供了洞察力.
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
- 计算化学的计算化学
背景情况:
- 电气双层电容器 (EDLC) 是重要的储能设备.
- 碳纳米管森林和碳化物衍生的碳是EDLCs有前途的电极材料.
- 了解EDLC性能的分子水平对于优化至关重要.
研究的目的:
- 使用碳纳米管森林进行EDLC的第一个分子级模拟.
- 为了确定单个电极容量,并研究孔径大小的影响.
- 为影响EDLC性能的解因素提供数据.
主要方法:
- 用碳纳米管森林电极对EDLC进行分子动力学模拟.
- 在纳米尺度上模拟孔径几何和离子相互作用.
- 单个电极容量的计算.
主要成果:
- 模拟的单电极电容大约为80 F/g.
- 容量显示,随着孔径在1nm以上的减少,容量略有增加.
- 结果与碳纳米管和碳化物衍生碳电极的实验数据一致.
结论:
- 分子模拟为EDLCs提供了准确的电容预测.
- 孔径大小显著影响电容,较小的孔径 (>1 nm) 提高性能.
- 模拟数据将通过隔离关键的物理化学因素来帮助理解和优化EDLC材料.
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