一个在现场减弱的全反射红外研究,一个奇拉的催化固体-液体接口: cinchonidine吸附在 pt 上
1Laboratory of Technical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, CH-8093 Zürich, Switzerland.
Journal of the American Chemical Society
|November 29, 2001
概括
在催化剂上的辛尼丁吸附是复杂的,观察到多种结合模式. 了解这些模式对于优化化反应至关重要.
科学领域:
- 不同质的催化剂.
- 表面科学是一门科学.
- 基质化学 基质化学 基质化学
背景情况:
- 性催化剂对于选择性合成至关重要.
- 辛尼丁是金催化剂的关键性修饰剂.
- 了解 cinchonidine 吸附对于反应优化至关重要.
研究的目的:
- 在Pt/Al(2) O(3) 模型催化剂上研究辛尼丁的现场吸附行为.
- 阐明 cinchonidine 度与其吸附模式之间的关系.
- 了解对酶选择性化反应的影响.
主要方法:
- 在现场减弱全反射 (ATR) 光谱.
- 在Pt/Al(2) O(3) 模型催化剂上研究辛尼丁吸附.
- 实验在与异质选化相关的条件下进行.
主要成果:
- 辛尼丁的吸附取决于覆盖面,在Pt表面上共存多种物种.
- 在低度下,平面吸附占主导地位;在高度下,倾斜的物种 (alpha-H抽象和N单双结合) 出现.
- 吸附剂层组成的缓慢过渡是由辛尼丁度驱动的,这对催化剂性能有影响.
结论:
- 辛尼丁在Pt/Al(2) O(3) 上的吸附是复杂的,并且取决于覆盖范围.
- 吸附物种的动态平衡会影响催化活性.
- 辛尼丁与溶剂分解产品竞争,影响溶剂在化过程中的溶剂效应.
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