离子诱导的电荷转移状态的形成在合的多电解质中
Justin M Hodgkiss1, Guoli Tu, Sebastian Albert-Seifried
1Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, UK. justin.hodgkiss@vuw.ac.nz
Journal of the American Chemical Society
|June 2, 2009
概括
结合聚合物薄膜中的离子产生电荷转移状态,灭发光. 这项研究使用时间分辨率光谱学解释了这一现象,为聚合物光伏设备提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 光物理学的光学物理学
- 聚合物化学 聚合物化学
背景情况:
- 结合聚合物是有机电子学中的关键.
- 含有离子的聚合物薄膜中的发光灭是一个已知的问题.
- 了解火机制对于设备优化至关重要.
研究的目的:
- 阐明含有离子的合聚合物的发光火背后的机制.
- 研究电荷转移 (CT) 状态在离子诱导火中的作用.
- 探索离子工程在聚合物光伏设备中的潜力.
主要方法:
- 时间分辨率光学光谱学 (光发光和短暂吸收).
- 基于F8BT的特定合聚电解质 (CPE) 的合成和表征.
- 取决于温度的光发光度测量.
主要成果:
- 在CPE薄膜中的发光灭归因于离子稳定电荷转移状态.
- CT状态是红移,寿命较长,不动.
- 在CT状态形成之前,兴奋子跳跃到离子区域被热激活 (E(act) = 28 meV).
- 与原始聚合物相比,聚电解质薄膜中的光发光量子效率显著下降.
结论:
- 电荷转移状态的离子诱导稳定是合聚电解质的一般机制.
- 这种现象可以用来控制激发动态.
- 在聚合物太阳能电池中,将激子流向电荷分离接口的潜力.
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