在低带隙共聚合物混合物中,链间相互作用,激子移位和电荷分离之间的关系
Zhi Guo1, Doyun Lee, Richard D Schaller
1Radiation Laboratory, ‡Department of Aerospace and Mechanical Engineering, and §Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States.
Journal of the American Chemical Society
|June 24, 2014
概括
供体-接受体共聚合物的高聚合物结晶性减缓了由于不利的链间激子而导致的电荷分离,需要新的太阳能电池设计. 这与P3HT同聚合物的行为形成鲜明对比.
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
- 聚合物化学 聚合物化学
背景情况:
- 供体-接受体共聚物是高效太阳能电池的关键.
- 了解电荷分离动态对于设备性能至关重要.
研究的目的:
- 研究结晶性和链间相互作用对PBDTTT共聚物的电荷分离的影响.
- 阐明链内和链间物种在超快电荷分离路径中的作用.
主要方法:
- 在PBDTTT共聚合物中基侧链的系统变化.
- 结合了超快光谱学和计算量子化学.
- 能量水平,兴奋状态结构和动态的表征.
主要成果:
- 线性侧链促进结晶性和链间激子的形成.
- 较高的晶度导致由于较粗的相隔离,电荷分离速度较慢.
- 低带隙共聚合物的链间激子在能量上不利于电荷分离.
结论:
- 针对低带隙共聚合物的优化太阳能电池形态必须与基于P3HT的设备不同.
- 长距离的晶体域可能会对低带隙共聚合物太阳能电池的性能产生不利影响.
- 定制分子包装对于有机光伏中有效的电荷分离至关重要.
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