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光刺激的共价连接转化异构化共价有机框架,以提高光催化性能

Zheng Lin¹, Shujing Liu¹, Weijun Weng¹

¹State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China.

Small (Weinheim an der Bergstrasse, Germany)

|October 24, 2023

概括

研究人员开发了一种使用光异构化来破坏共价有机框架 (COF) 中对称性的新策略. 这通过改善电荷分离,提高了它们用于光催化生产的效率.

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
有机化学有机化学

背景情况:

联有机框架 (COF) 由于其可调节的结构,对光催化有希望.
在COF中对称的染色体排列可以通过增强激素脱局限性来限制光化学反应.

研究的目的:

开发一种策略,以打破多染色体COFs中的兴奋状态对称性.
通过控制刺激效应和电荷分离来增强光催化活性.

主要方法:

使用光异构化驱动的方法在胺相关的COF中.
嵌入了吸收电子的西迪亚醇单元,以促进超快激发状态的分子内质子转移 (ESIPT).
调整了 imine 与 enamine 连接的比率,以控制电子结构和电荷分离.

主要成果:

在140 fs内实现超快速ESIPT,产生部分化COF异构体并打破激发状态对称性.
混合的伊米内-胺链接改变了电子对称性,促进了光诱导的电荷分离.
增加的 imine-to-enamine比率增强了远程电子转移,并优化了的演化率.

结论:

引入了ESIPT诱导的光异构化策略,用于对称性破坏的COF.
在工程化COF中,证明了减弱刺激效应和增强光化学反应性.
通过控制的对称性破坏和电荷分离,实现了优化的光催化进化.

关键词:

共价有机框架是共价有机框架.的进化的进化的进化光异构化是指光异构化的过程.质子转移是转移质子的过程.

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