对捐赠体-接受体光诱导的电荷分离进行超分子控制
Alicia Marcos Ramos1, Stefan C J Meskers, Edwin H A Beckers
1Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|August 5, 2004
概括
这项研究创造了一个新的捐赠者-桥梁-接受者系统. 系统 系统 系统
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
- 摄影化学的使用.
背景情况:
- 捐赠者桥接收器 (DBA) 系统对于人工光合作用和分子电子学至关重要.
- 控制捐赠器和接受器单位之间的距离和相互作用是优化电荷分离效率的关键.
- 寡合桥提供可调节的形状灵活性,用于调节DBA相互作用.
研究的目的:
- 综合和描述一个具有灵活的寡合桥梁的新型DBA系统.
- 为了研究溶剂极性对寡合桥形状的影响.
- 为了将桥梁形状与光诱导的能量和电荷转移过程相关联.
主要方法:
- 一个p-phenylene vinylene (OPV) -m-phenylene ethynylene (FOLD) -perylene diimid (PERY) 系统的共价合成.
- 在不同的溶剂极性 (chloroform,heptane) 中进行光谱表征.
- 分析光刺激动态,以确定能量和电荷转移路径.
主要成果:
- 寡头桥采用极性溶剂中的随机线圈,并在非极性溶剂中折叠成螺旋堆.
- 光刺激导致随机卷轴构造中的分子内能量转移.
- 在折叠的形状中,电荷分离状态 (OPV(+) - FOLD-PERY(-)) 是受欢迎的,特别是在非极性介质中.
- 在非极性溶剂中,由于桥梁折叠,光诱导的电荷分离显著增强.
结论:
- 寡合桥的形状灵活性决定了光诱导电荷分离的效率.
- 无极介质促进桥梁折叠,使供体和受体单位更接近并增强电荷分离.
- 这项工作展示了一种新的策略,通过调整溶剂诱导的形状变化来控制DBA系统中的电荷分离.
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