在单分子结合中,地面和激发状态之间的曲向平面光循环的光导率
Qi Zou1, Xuanying Chen1, Yu Zhou2
1Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
Journal of the American Chemical Society
|May 25, 2022
概括
由于光诱导的平面化,DPAC-SMe的单分子导电性在光下显著增加. 这项研究揭示了分子结合中的可调光电荷传输.
科学领域:
- 分子电子
- 摄影化学
- 有机电子
背景情况:
- 9,14-二-9,14-二丁 (DPAC) 等分子的曲向平面光循环对于理解激发状态动态至关重要.
- 研究单分子导电性可以直接了解电子特性和结构变化.
研究的目的:
- 在单个分子水平上探索DPAC衍生物 (DPAC-SMe) 的光导率.
- 将光引起的结构变化与电导率的变化相关联.
- 了解光电导电增强背后的机制.
主要方法:
- 使用扫描道显微镜断裂连接技术制造单分子连接.
- 在340nm光照射下测量DPAC-SMe连接的电导率.
- 用光和不用光,以及在宏环化 (结构固定) 分子中的电导率的比较.
- 在现场使用脉冲光进行电导度调制的监测.
- 理论计算以阐明电子结构和共振现象.
主要成果:
- 在连续340nm光照射下,DPAC-SMe连接表现出高达200%的导电增强.
- 当分子结构进化被宏循环化阻止时,光导被废除.
- 在现场测量证实了光导电量调制.
- 光诱导的分子内平面化被确定为光导的来源.
- 理论计算显示光诱导的电子云再分配和法诺共振,解释电导率的增加.
结论:
- 单分子导电性对光诱导的结构动态敏感,特别是曲向平面的光循环.
- DPAC-SMe在单个分子水平上展示了可调节的电荷传输特性.
- 这项工作为设计具有可调节电荷传输特性的有机光电子设备提供了途径.
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