在多变体金属有机框架中调节双位点的电荷,以促进烯的选择性有氧化
Hanlin Liu1,2, Wei Liu1,2, Guangxin Xue1
1CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
Journal of the American Chemical Society
|May 10, 2023
概括
这项研究在金属有机框架 (CuCo-MOF-74) 中引入了使用空气的选择性烯环氧化. 这种催化剂实现了高氧化物选择性和稳定性,克服了基功能化的挑战.
科学领域:
- 材料科学
- 催化剂
- 有机化学
背景情况:
- 对于工业应用而言,选择性有氧环氧化非常重要.
- 实现高选择性和避免CC键裂变等副作用仍然是一个重大挑战.
研究的目的:
- 开发一种用于高度选择性氧化的新型催化系统.
- 在多变体金属有机框架 (CuCo-MOF-74) 中制造和研究CuI单点的性能.
主要方法:
- 溶解热合成CuCo-MOF-74与部分减少Cu (II) 的Cu (I).
- 框架内单个Cu (I),Cu (II) 和Co (II) 站点的表征.
- 使用空气作为氧化剂测试烯环氧化的催化活性和选择性.
- 进行对比实验和理论计算以阐明催化机制.
主要成果:
- 在高氧化转化率下,CuCo-MOF-74对氧化物 (87.6%) 具有很好的选择性.
- 与Co-MOF-74相比,该催化剂具有较强的选择性和良好的催化稳定性.
- 理论计算表明,Cu (I) 位点在双 Co (II) 和Cu (I) 位点上促进 O2 激活,增强了环氧化选择性.
- 催化剂还显示出对其他的氧化有很好的选择性.
结论:
- 在CuCo-MOF-74中加入Cu(I) 单点显著提高了有氧环氧化选择性.
- 在Cu (I) 和Co (II) 位点之间的协同作用是激活氧气和促进所需反应的关键.
- 这种方法为制造其他金属有机框架中高效的氧化催化剂提供了有希望的策略.
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