在分子批量异质连接材料中的光诱导电荷生成
Loren G Kaake1, Jacek J Jasieniak, Ronald C Bakus
1Center for Polymers and Organic Solids, University of California-Santa Barbara, Santa Barbara, California 93106, United States. lkaake@physics.ucsb.edu
Journal of the American Chemical Society
|November 8, 2012
概括
在有机光伏中,由于激发状态的移位,电荷载体在100 femtosecond内产生. 这种超快的过程,在分子和聚合物散体异质连接中观察到,是提高设备效率的关键.
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
- 频谱学是一种光谱学.
背景情况:
- 了解充电生成对于提高有机光伏 (OPV) 设备效率至关重要.
- 尽管进行了广泛的研究,但在OPV中电荷生成和再组合的完整模型仍在开发中.
研究的目的:
- 研究高性能有机光伏批量异质连接 (BHJ) 混合物的超快电荷光生成和重组动力学.
- 为了比较溶液处理的分子BHJ和基于聚合物的BHJ材料中的这些动态.
主要方法:
- 超快速的短暂吸收光谱学.
- 极化异质性测量. 分极化异质性测量.
- 研究溶液加工分子BHJ的纯薄膜.
主要成果:
- 大多数电荷载体在分子和聚合物BHJ中都在<100 fs中产生.
- 激发状态移位被认为是超快速电荷转移的机制.
- 对异质连接的激发扩散在1-500 psi之间观察到.
- 纯分子片显示了由分子刺激子主导的快速非局部化电荷产生 (t < 100 fs).
结论:
- 超快速充电生成 (<100 fs) 是高性能有机BHJ的一个关键特征,由兴奋状态移位驱动.
- 兴奋子扩散在较长的时间尺度上起作用.
- 结果为设计更高效的有机光伏材料提供了洞察力.
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