已订购的溶剂和离子液体可用于静电催化
Longkun Xu1, Ekaterina I Izgorodina2, Michelle L Coote1
1ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia.
Journal of the American Chemical Society
|July 3, 2020
概括
应用外部电场可以调节溶剂,实现静电催化. 这种有序的溶剂环境即使在电场被移除后也显著降低了反应激活能量,这表明有效的化学反应的脉冲场策略.
科学领域:
- 计算化学
- 物理化学
- 化学反应的动态
背景情况:
- 外部电场可以影响分子行为和反应路径.
- 溶剂排序在化学反应动力学和机制中起着至关重要的作用.
研究的目的:
- 研究由外部电场引起的溶剂排序效应.
- 要确定这个有序的溶剂是否可以在没有应用场的情况下以静电催化反应.
- 在有序与无序的溶剂环境中比较催化效应.
主要方法:
- 基于德鲁德振荡器的极化力场的经典分子动力学模拟.
- 进行量子化学计算.
- 通过ONIOM的多尺度计算.
主要成果:
- 一个0.2V/Å的外部电场显著要求甲醇和离子液体 ([EMIM][BF4]) 溶剂.
- 即使没有应用场,有序溶剂环境也会使转移反应的激活能量降低20kcal/mol (甲醇) 和30kcal/mol ([EMIM][BF4]).
- 即使是0.1V/场也显示出相当大的催化效应.
结论:
- 外部诱导的溶剂排序可能导致显著的静电催化.
- 脉冲外场策略可以保持催化剂的排序,同时尽量减少反应期间的外场暴露.
- 这种方法提供了一种通过受控溶剂环境提高化学反应速率的新方法.
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