在氧化物表面的核友性攻击中,甲的热驱动的高反应性
Shuai Wang1,2, Enrique Iglesia2
1State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China.
Journal of the American Chemical Society
|January 4, 2018
概括
表面催化驱动高度选择性的C-C合反应. 甲醇脱和甲 (HCHO) 与乙烯酸盐的合是由驱动的,由于减少过渡状态组织,有利于HCHO.
科学领域:
- 不同质的催化
- 表面化学
- 有机合成
背景情况:
- 在化学合成中,甲醇 (CH3OH) 的脱和随后的C-C合是至关重要的.
- 了解催化剂表面的反应选择性是有效化学过程的关键.
研究的目的:
- 调查甲 (HCHO) 和酸盐之间的C-C合在anatase TiO2表面的高特异性.
- 阐明控制这种选择性的基本热力学和运动因素.
主要方法:
- 用HCHO和结合的速率常数的实验测量.
- 这些反应中过渡状态 (TS) 的自由能量的理论计算.
- 对反应选择性的和贡献的分析.
主要成果:
- 与乙烯酸相比,乙烯酸的合速度是10^3倍以上.
- 高选择性主要是由HCHO反应的过渡状态 (TS) 中较小的损失驱动的.
- 表面施加的结构组织显著影响TS,有利于像HCHO这样的较小电友.
结论:
- 表面催化C-C合表现出独特的驱动特异性,由于最小的惩罚,有利于甲 (HCHO).
- 这种选择性对于使用HCHO作为C1构件在表面介导合成中至关重要.
- 这些发现突显了表面诱导的效应在催化中的独特作用.
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