对块共聚合物光伏材料模型系统中链内电荷转移的控制
Kerr Johnson1, Ya-Shih Huang, Sven Huettner
1Cavendish Laboratory, University of Cambridge , J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
Journal of the American Chemical Society
|March 14, 2013
概括
我们研究了合聚合物,以了解链内电荷分离. 结合聚3-基硫) 到硫-二甲-硫迅速形成的电荷转移状态.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 光物理学的光学物理学
背景情况:
- 结合的供体-受体块共聚物对有机电子学至关重要.
- 了解链内电荷分离是提高设备效率的关键.
- 传统的供体-接受体混合物主要表现出链间电荷分离.
研究的目的:
- 为了研究捐助者和接受者段之间的结合链的电子性质.
- 为了建模和研究区块共聚物内的链内光诱导的电荷分离.
- 探索结合链接结构对兴奋状态修改的影响.
主要方法:
- 合成包括多3-基硫 (P3HT) 和单个F8-TBT单元的模型结合系统.
- 电子属性的表征,包括吸收和发射频谱.
- 超快速光谱分析以确定电荷转移状态形成动态 (<40 fs).
主要成果:
- 将P3HT直接合到烯-乙-乙-乙 (TBT) 单元导致局部电荷转移状态,带有红移光谱.
- 这种链内电荷转移状态迅速 (<40 fs) 和高效地形成,但寿命短暂 (<1 ns).
- 使用二氧化 (F8) 单元分离P3HT和TBT显示了最小的电子状态修改,但使电荷分离状态的寿命更长.
结论:
- 结合连接强烈影响激发状态动力学和捐赠者-接受者系统中的电荷分离机制.
- 链内电荷转移状态可以快速有效地形成,但它们的寿命受到分子结构的限制.
- 更宽的带隙连接器可以促进更长寿命的电荷分离,为改善有机电子设备性能提供潜力.
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