在碳纳米环的包容性复合体中的光诱导电子转移
Olga A Stasyuk1, Alexander A Voityuk1, Anton J Stasyuk1
1Institute of Computational Chemistry and Catalysis and Department of Chemistry, University of Girona, C/ M. Aurèlia Capmany, 69, 17003 Girona, Catalonia, Spain.
Accounts of chemical research
|December 16, 2023
概括
碳材料中的光诱导电子转移是光能转换的关键. 碳纳米环和富勒烯复合体的修改显著影响电子转移效率,使定制的光伏应用成为可能.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
背景情况:
- 碳材料中的光诱导电子转移 (PET) 对光能转换至关重要.
- 富勒和环烯 (CPP) 等碳材料具有独特的电子特性,适合PET研究.
- 这些材料是光伏设备的重要组成部分,作为传输层,电极或添加剂.
研究的目的:
- 调查结构修改对碳纳米圈-富勒林纳入复合体中PET效率的影响.
- 了解如何改变宿主和客分子影响电荷分离和重组动态.
- 为优化光活性应用程序计算设计新型碳纳米环系统.
主要方法:
- 利用时间依赖密度函数理论 (TD-DFT) 与塔姆-丹科夫近似 (TDA) 和CAM-B3LYP函数用于激发状态计算.
- 采用非电传递理论来量化电子传递速率.
- 在合成和计算设计的纳入复合体中模拟电荷分离和重组.
主要成果:
- 将π-结合碎片或反芳单元纳入碳纳米环中会改变光物理性质,并引入新的电荷转移状态.
- 化将纳米环从电子捐赠者转变为接受者;空缺缺陷阻碍了PET,而扩展的π-系统增强了捐赠者的特性.
- 纳米环单元的芳香性决定了电子转移方向,芳香单元通常充当捐赠者,反芳香单元充当接受者.
结论:
- 碳纳米环的结构修改,包括π-结合, perfluorination,和反芳香性,提供对PET效率的有效控制.
- 与中性C60.0相比,带电的富勒烯显示出优越的电子受体能力.
- 考虑到电荷位置和溶剂极性,捐赠器-接受器系统的战略设计可以通过可调节的电荷传输频段提高光伏性能.
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