对水氧化催化剂的交界质子合电子转移的重组能量
Matthew Kessinger1, Alexander V Soudackov2, Jenny Schneider1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States.
Journal of the American Chemical Society
|October 31, 2022
概括
这项研究量化了水氧化催化中的界面电子转移 (ET) 和质子合ET (PCET) 的重组能量. 研究结果显示,高pH的太阳水氧化具有动力优势,证明了马库斯 - 格里舍理论
科学领域:
- 光催化
- 无机化学
- 物理化学
背景情况:
- 有效的太阳水氧化需要了解界面电子转移 (ET) 和质子合ET (PCET) 动力学.
- 马库斯-格里舍理论对于分析外星人反应中的重组能量至关重要.
- 将这一理论扩展到PCET对于优化催化过程至关重要.
研究的目的:
- 确定从氧化 (ITO) 到水氧化催化剂的界面ET和PCET的重组能量 (λ).
- 研究pH对这些界面反应的动力学的影响.
- 为了验证马库斯-格里舍理论的扩展到PCET.
主要方法:
- 在可见光照射下对界面ET和PCET反应的动态分析.
- 马库斯-格里舍理论应用于实验数据以提取重组能量.
- 计算模型以阐明内部球体重组的能量贡献.
主要成果:
- 确定了重组能量:对于ET,λ=0.40±0.02 eV,对于PCET,λ=0.90±0.02 eV.
- 与ET不同的是,PCET的速率常数随着pH的增加而下降.
- 通过计算证实了PCET更大的内部球体重组能量.
结论:
- 马库斯-格里舍理论可以可靠地扩展到PCET,提供对反应机制的见解.
- 由于减少了竞争PCET,太阳水氧化在高pH下受到动力优势.
- 了解重组能量是设计高效光催化剂的关键.
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