乙烯连接的共价有机框架可见光促进选择性氧化在水中的烯
Jun Wang1, Shujie Qiao1, Mingshuan Yang1
1College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|December 4, 2024
概括
新的捐赠者-受体维尼林结合的共价有机框架 (COFs) 增强了 styrene 氧化的光催化活性. 这些先进的COF在有机转化中表现出高效率和选择性,即使在水性介质中.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 聚合物化学 聚合物化学
背景情况:
- 乙烯联共价有机框架 (COF) 是有希望的异质光催化剂,因为它们的有序结构和稳定性.
- 然而,它们的光催化效率往往受到高刺激子结合能和差刺激子解离的限制.
研究的目的:
- 通过在COF骨架中设计捐助者-接受者 (D-A) 对来克服传统COF的局限性.
- 为了提高电荷转移和分离,提高光催化性能.
主要方法:
- 通过阿尔多尔凝结合成两种D-A型维尼林结合COF (TMT-BT-COF和TMT-TT-COF).
- 使用丁诺和索作为捐赠剂和三氨酸单位作为接受剂.
- 光化学,电化学和密度功能理论 (DFT) 研究以分析电荷动态.
主要成果:
- 合成的DACOF表现出高效的电荷转移和抑制的电荷重组.
- 两种TMT-BT-COF和TMT-TT-COF都在使用分子氧气 (转化≥92%,选择性≥90%) 将烯氧化为甲时表现出高的催化活性.
- 在NaHCO3.3的存在下,在水中实现了烯的光催化环氧化,对烯氧化物具有53%的选择性.
结论:
- 加入D-A对显著提高了维尼林结合的COF的光催化效率.
- 这些材料显示出在水性介质中进行高效的有机转化的潜力,为COF应用开辟了新的途径.
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