质子合电子转移的pH依赖的一般动态模型:应用于电化学水氧化系统
Kai Cui1, Alexander V Soudackov1, Matthew C Kessinger2
1Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|August 23, 2023
概括
一个新的模型解释了pH如何影响质子合电子转移 (PCET) 反应. 弱pH依赖源于相互竞争的反应路径,对于理解化学和生物过程至关重要.
科学领域:
- 化学动力学
- 电化学
- 催化剂
背景情况:
- 质子合电子转移 (PCET) 反应在化学和生物学中至关重要.
- 了解它们的pH依赖是解释机制的关键.
研究的目的:
- 介绍PCET反应中的pH依赖性的一般动态模型.
- 解释在电化学PCET中观察到的弱pH依赖.
主要方法:
- 为同质和电化学PCET开发了一种多通道运动模型.
- 将模型应用于以为基础的水氧化催化剂.
- 分析实验数据以验证模型的预测.
主要成果:
- 由于具有不同贡献的竞争性PCET通道,pH依赖性较弱.
- 模型准确地解释了催化剂的实验观测.
- 在较高的pH值下,最大速率常数的pH独立性得到预测和确认.
结论:
- 多个竞争道对于准确的PCET机制分析至关重要.
- 主导途径从电子转移到顺序PCET随着pH的增加.
- 该模型为了解PCET中的复杂pH效应提供了一个框架.
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