乙烯对的吸附:动力学,结合,以及对催化作用的相关性
Helmut Ofner1, Francisco Zaera
1Department of Chemistry, University of California, Riverside, California 92521, USA. francisco.zaera@ucr.edu
Journal of the American Chemical Society
|September 13, 2002
概括
在金表面的乙烯吸附显示了两个不同的状态:不可逆转的d-sigma和可逆的pi. 在高覆盖率下,这些状态可以相互转换,这表明了集体分子重排机制.
科学领域:
- 表面科学是一门学科.
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 在金属表面的乙烯吸附对于催化是至关重要的.
- ((111) 是一个模型催化剂表面.
- 了解吸附状态可以告知反应机制.
研究的目的:
- 对的乙烯吸附状态进行研究{111}.
- 阐明吸附状态的动力学和相互转换.
- 提出一种高覆盖度吸附机制.
主要方法:
- 可能使用了表面科学技术 (例如LEED,XPS,TPD).
- 吸附和脱附的动态分析.
- 取决于覆盖范围的研究.
主要成果:
- 确定了两个乙烯吸附状态:二位数 (不可逆转) 和pi (可逆转).
- 对每个状态观察到显著不同的动力行为.
- 在高覆盖率的情况下,两个州之间表现出缓慢的相互转换.
结论:
- 在上,高覆盖率乙烯吸附 ((111) 涉及复杂的相互作用.
- 一个拟议的机制涉及初始位点相互作用,其次是集体分子重新排列.
- 这为不完美的单层形成和压缩层提供了洞察力.
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