关于低温水气转移反应对铜的机制
Amit A Gokhale1, James A Dumesic, Manos Mavrikakis
1Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|January 10, 2008
概括
在Cu(111) 上的水气转移反应主要由碳酸介导的路径主导,初始的水抽取作为速度限制的步骤. 这项研究揭示了使用密度函数理论对反应机制的新见解.
科学领域:
- 表面科学和催化剂.
- 计算化学和材料科学计算化学和材料科学
背景情况:
- 水气转移反应 (WGSR) 对于生产至关重要.
- 了解铜催化剂上的WGSR机制对于优化工业流程至关重要.
研究的目的:
- 通过密度函数理论 (DFT-GGA) 对Cu{111) 的WGSR机制进行研究.
- 识别关键的中间体和反应途径,包括一种新的碳素介导路径.
主要方法:
- 定期,自我一致的密度函数理论 (DFT-GGA) 计算.
- 基于DFT的实验反应速率的详细微动力学建模.
主要成果:
- 鉴定出一种新的反应性中间体 - - 碳酸,它是Cu上的WGSR的核心.
- 在实验条件下,碳素介导路径是主要的路径.
- 从水中提取最初的是限制速度的步骤.
结论:
- 碳素介导途径显著改变了对Cu的WGSR的理解.
- 微动力学建模为表面覆盖面,激活能量和反应顺序提供了预测能力.
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