基于Pyrene-Alkyne的合多孔聚合物与骨架扭曲介导的⋅O2和O2为高选择性有机光合作用生成
Guobang Li1, Tianyu Qiu1, Qi Wu1
1Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Faculty of Chemistry, Faculty of Physics, Northeast Normal University, Changchun, 130024, China.
Angewandte Chemie (International ed. in English)
|May 31, 2024
概括
这项研究详细介绍了修改聚合物结构如何影响反应性氧物种 (ROS) 的产生,从而导致高度选择性的光催化. 定制结合多孔聚合物 (CPP) 能够精确控制 ROS,以实现高效的化学反应.
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:
- 反应性氧物种 (ROS) 在光催化过程中至关重要,但它们在聚合物系统中的调节尚未得到充分研究.
- 合多孔聚合物 (CPPs) 为光催化应用提供可调节的结构.
研究的目的:
- 通过改变链接单位来研究基于烯基的CPP中的结构-活性关系.
- 了解骨修饰如何影响激发性行为和ROS生成 (超氧化基⋅O2-和单片氧1O2).
- 为了实现选择性的ROS生成,以提高光催化性能.
主要方法:
- 一系列基于乙烯 (TEPY) 的CPPs与不同的链接剂 (1,4-二二 (BE),4,4'-二二 (IP),3,3'-二二 (BP)) 的合成.
- 实验性表征和理论计算来分析聚合物结构和电子特性.
- 在氧化和循环添加反应中对光催化活性的评估.
主要成果:
- BE-TEPY具有平面结构,有利于⋅O2-生成,在酸氧化和 [3+2]循环添加 (>99%的转化和选择性) 中表现出高活性.
- 具有扭曲结构的BP-TEPY增强了O2生成的系统间交叉 (ISC),在 [4+2] 循环添加和 thioanisole 氧化 (>99% 转化和选择性) 中表现出色.
- 在CPP骨结构,刺激性质和选择性ROS产生之间建立了明确的相关性.
结论:
- CPPs的骨架结构本质上决定了激发性行为和特定ROS的选择性生成.
- 基于结构-活动关系的CPP的合理设计可以导致高效和选择性的光催化剂.
- 这项工作为开发针对性化学转换的先进聚合物光催化剂提供了基本的见解.
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