支持的分子催化剂:金属核的分解效应和支持作为连接体的支持
Jing Lu1, Pedro Serna, Ceren Aydin
1Department of Chemical Engineering and Materials Science, University of California-Davis, One Shields Avenue, Davis, California 95616, United States.
Journal of the American Chemical Society
|August 27, 2011
概括
这项研究揭示了以乙烯化中的催化剂性能如何取决于支性质. 电子捐赠的MgO支器需要团来激活H2,不同于取电子的HY热.
科学领域:
- 不同质的催化剂.
- 表面科学是一门科学.
- 材料化学 材料化学
背景情况:
- 催化剂的性能取决于金属的大小,结构,连接体和支.
- 由于缺乏系统变化的催化场所,了解这些因素是具有挑战性的.
- 同结构的物种为剖析这些效应提供了一个模型.
研究的目的:
- 为了阐明支特性对化催化乙烯化的影响.
- 为了区分电子捐赠 (MgO) 和电子吸收 (HY热) 支器的作用.
- 为了将催化活性与分子级催化剂行为相关联.
主要方法:
- 在MgO和HY岩支上合成同结构性体物种.
- 在现场对工作催化剂进行光谱分析.
- 乙烯化的动力学研究.
主要成果:
- MgO上的催化速率取决于H2解离,受核性 (单核与四核) 的影响.
- 在HY焦石上,H2解离的速度并没有限制,即使是单个原子.
- 邻近的位对MgO至关重要,但对HY化石至关重要,用于H2和乙烯激活.
结论:
- 支持性质显著改变了催化乙烯化反应机制.
- 提取电子的热利特支物甚至在单个原子水平上也促进了催化作用.
- 电子捐赠的MgO支持器需要多核位,以实现高效的催化.
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