聚合物/富勒烯批量异质连接膜中的双质电荷重组合以及对太阳能电池功能的影响
Suman Kalyan Pal1, Tero Kesti, Manisankar Maiti
1Chemical Physics, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Journal of the American Chemical Society
|August 14, 2010
概括
我们研究了烯衍生物如何影响聚合物/烯太阳能电池中的电荷动态. 不同的衍生品影响电荷重组率,内部电场对于设备中有效的电荷提取至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 太阳能光伏发电是如何实现的
- 有机电子 有机电子
背景情况:
- 聚合物/富勒烯批量异质连接 (BHJ) 太阳能电池对可再生能源具有前景.
- 了解充电生成和重组动态是提高设备效率的关键.
研究的目的:
- 调查三种不同的富勒烯衍生物对BHJ太阳能电池中电荷生成和再组合的影响.
- 为了将电荷动力学与富勒烯衍生物和设备物理学的特性相关联.
主要方法:
- 在APFO3/富勒烯BHJ混合物中研究了电荷生成和重组动态.
- 分析了电荷转移速率,并将其与LUMO能量和材料特性相关联.
主要成果:
- 对APFO3/[70]PCBM和APFO3/[60]PCBM的电荷生成类似,但比APFO3/[70]BTPF慢,与LUMO能量差异保持一致.
- 双胞胎电荷重组率有显著的变化,以APFO3/[70]PCBM < APFO3/[60]PCBM < APFO3/[70]BTPF的顺序增加.
- 观察到的重组率不能仅仅由LUMO能量来解释,这表明电荷移动性和分离距离的作用.
结论:
- 双质重组受电荷分离距离和材料特异性电荷移动性的影响.
- 在BHJ太阳能电池中,内部电场,极化和极子动力学对于克服电子孔吸引力和实现有效的电荷提取至关重要.
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