具有工程疏水微环境的非对称单原子催化剂:有效的甲基酸氧化反应-运输合策略
Huiling Feng1,2, Yanyan Li1, Yu Guan2
1College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Journal of the American Chemical Society
|August 5, 2025
概括
研究人员开发了一种用于生产环氧化植物油 (EVO) 的新催化剂. 这项创新利用不对称的单原子位和疏水环境来提高绿色化学替代品的效率和选择性.
科学领域:
- 催化剂
- 材料科学
- 绿色化学
背景情况:
- 越来越多的生物降解替代品需要有效地转换可再生资源.
- 目前生产环氧化植物油 (EVO) 的方法面临着低催化活性和选择性的挑战.
- 植物油的转化对于可持续的化学生产至关重要.
研究的目的:
- 开发一种有效的策略来增强甲基油酸环氧化,一种植物油转化模型.
- 克服目前EVO生产方法的低活性和选择性的局限性.
- 设计一个结合活跃站点和定制微环境的催化剂,以提高性能.
主要方法:
- 具有不对称单原子Co-N2-O2位点的催化剂的设计和合成.
- 使用无基植入表面设计一种疏水微环境.
- 在环境条件下使用O2作为氧化剂对甲基酸盐的环氧化进行研究.
- 进行机制研究以了解活动地点和微环境的作用.
主要成果:
- 实现了1356小时的转换频率和99%的甲基酸环氧化选择性.
- 由于不对称的CoN2O2协调,证明了增强的O2激活和电子反应.
- 从疏水微环境中观察到超过3倍的活性增强,促进基质分离并增加局部O2度.
- 确定了一种"反应-运输合"机制,驱动高性能.
结论:
- 开发的催化剂结合了不对称的单原子位点和水微环境,显著提高了EVO生产效率和选择性.
- 这种方法为工业生产环氧化植物油提供了可扩展和节能的途径.
- 通过协同结合主动站点工程与微环境修改,为催化剂设计提供了可通用的范式.
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