通过短暂吸收光谱学研究的聚乙烯/富勒烯混合膜中电荷载体的形成
Hideo Ohkita1, Steffan Cook, Yeni Astuti
1Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom. ohkita@photo.polym.kyoto-u.ac.jp
Journal of the American Chemical Society
|February 19, 2008
概括
这项研究比较了聚乙烯薄膜及其与PCBM的混合物,揭示了有机太阳能电池中高效的电荷生成需要更大的能量差异来进行电荷分离,而不是光发光衰减. 这一发现指导了材料的优化,以提高太阳能电池性能.
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
- 有机电子 有机电子
背景情况:
- 聚二是有机电子产品中的关键材料.
- 了解光物理对于优化有机太阳能电池性能至关重要.
- 聚烯和烯受体 (如PCBM) 之间的相互作用会影响电荷生成效率.
研究的目的:
- 为了比较各种聚乙烯在原始膜中的光物理和与PCBM混合时.
- 调查影响电荷生成和重组动态的因素.
- 为了将电荷分离的自由能量差异与电荷生成产量相关联.
主要方法:
- 暂时吸收光谱用于研究激发状态和极子.
- 光发光 (PL) 灭测量以评估激发行为.
- 通过功率定律衰变分析分析电荷载体动态的分析.
主要成果:
- 纯净的无形聚烯形成三双,而晶体的聚烯形成极子.
- 与PCBM混合有效地通过激发灭灭聚烯光发光 (PL).
- 电荷分离产量有很大差异,与电荷分离的自由能量差异相关 (deltaG(CS) rel).
结论:
- 在聚乙烯/PCBM混合物中高效的电荷生成需要相当大的deltaG(CS) rel,超过PL火.
- 极子对中的多余热能可能是克服库伦比结合所必需的.
- 这凸显了LUMO水平偏移对优化有机太阳能电池效率的重要性.
相关概念视频
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