在聚合物-富勒烯混合太阳能电池中,电荷转移状态与热激子解离相比
Jiye Lee1, Koen Vandewal, Shane R Yost
1Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 10, 2010
概括
热激子解离对聚合物富勒烯太阳能电池的影响最小. 研究表明,对于激子和直接电荷转移激发,内部量子产量是相似的,这表明热过程并不重要.
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
- 物理化学 物理化学
背景情况:
- 聚合物富勒烯太阳能电池是可再生能源的关键技术.
- 激发分离是将光转化为电力的关键步骤.
- 热激子解离是一种用于高效电荷生成的拟议机制.
研究的目的:
- 为了研究热激子解离在原型聚合物-富勒烯太阳能电池中的作用.
- 为了确定热过程是否对载体光生成有显著的贡献.
- 为了比较热激子解离与直接电荷转移激化的效率.
主要方法:
- 实验分析了两个原型的聚合物-富勒烯混合太阳能电池.
- 测量载体光生成的内部量子产量.
- 对电流-电压特征的温度依赖性的分析.
主要成果:
- 发现内部量子产量对于激子和直接电荷转移状态激发都是相似的.
- 电流-电压特征的温度依赖性表明热激子解离的影响是可以忽略不计的.
- 热激子解离似乎不是这些系统中电荷生成的主要途径.
结论:
- 在聚合物-富勒烯太阳能电池中热激子解离的意义是可以忽略不计的.
- 电荷生成主要通过既定的途径发生,而不是热激子解离.
- 可能需要进一步的研究来探索替代机制或材料系统.
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