评估界面电化学反应重组能量的方法
Karnamohit Ranka1,2, Sijia Ke1,2,3, Chenqi Fan1,2,4
1Liquid Sunlight Alliance, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
概括
这项研究将Butler-Volmer和Marcus-Hush-Chidsey (MHC) 形式主义结合起来,以准确预测电子转移速率. 它估计了重组能量及其对电极参数的依赖,以改进二氧化碳减排建模.
科学领域:
- 电化学 电化学 电化学
- 化学动力学 化学动力学
- 计算化学计算化学
背景情况:
- 巴特勒-沃尔默方程对于更高超电位的电子转移速率是不准确的.
- 马库斯 - 胡什 - 奇德西 (MHC) 形式主义提供了准确的非对称行为,但需要复杂的参数化.
研究的目的:
- 为了弥合巴特勒-沃尔默和MHC形式主义,以改进电子转移速率系数估计.
- 估计重组能量及其对内在参数的依赖.
- 开发一般关系来预测速度系数在一个广泛的超潜在的范围.
主要方法:
- 开发了一种混合方法,结合了巴特勒-沃尔默和MHC形式主义.
- 研究了重组能量对激活障碍,电子合和电极密度状态的敏感性.
- 在各种金属电极上应用了二氧化碳减排机制的方法.
主要成果:
- 成功估计了重组能量,这是一个关键的MHC参数.
- 建立了重组能量和内在系统参数之间的关系.
- 证明了在广泛的超电位范围内的速率系数的准确预测.
结论:
- 结合形式主义为电子转移速率计算提供了更准确和更通用的方法.
- 了解重组能量的依赖电极特性对于优化二氧化碳减排等电化学过程至关重要.
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