采集单点裂变用于太阳能转换:从量子力学叠加中转移一个电子而不是两个电子
Wai-Lun Chan1, John R Tritsch, X-Y Zhu
1Department of Chemistry & Biochemistry, University of Texas, Austin, Texas 78712, USA. wlchan@ku.edu
Journal of the American Chemical Society
|October 17, 2012
概括
单点裂变在四烯/C ((60) 中可以有效地提取多个电荷载体. 这项研究揭示了不同的1和2电子转移通路,这对于提高有机太阳能电池效率至关重要.
科学领域:
- 有机电子学有机电子学
- 太阳能光伏发电是如何实现的
- 刺激的动力学 刺激的动力学
背景情况:
- 单点裂变从单点激子中产生两个三重激子,从而提高太阳能电池的效率.
- 从这些激子中提取多个电子孔对是关键,但具有挑战性.
- 了解相互竞争的动态过程对于优化多电子转移至关重要.
研究的目的:
- 研究四烯/C 60中从单列 (S) 和多兴子 (ME) 状态进行一电子和两电子转移.
- 探测影响电荷传输效率的竞争动态过程.
- 建立在供体/接受体接口上高效的多重载体提取的设计原则.
主要方法:
- 时间分辨率光辐射光谱学应用于四烯/C60) 接口.
- 分析来自S(1) 和ME状态的电子转移动态.
- 一个和两个电子转移路径的动态分析.
主要成果:
- 单片裂变在四中比在五中慢 (~7 ps),允许不同的转移途径.
- 证据表明,由电子转移到C(60) 的LUMO和LUMO+1.1形成的两个不同的电荷转移状态.
- ~60%的刺激子通过S(1) 进行一次电子转移,而~40%通过ME进行两次电子转移.
- 量子力学上的S(1) 和ME状态的叠加影响了转移路径.
结论:
- 烯/C60) 系统展示了可控制的1和2电子转移通路.
- 接口设计对于优化从单片裂变中多载体提取至关重要.
- 这些发现为开发下一代有机太阳能电池和光探测器提供了洞察力.
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