全聚合物太阳能电池性能通过捐赠和接受聚合物的系统分子重量调节进行优化
Nanjia Zhou, Alexander S Dudnik, Ting I N G Li
1Chemical Sciences and Engineering Division, Argonne National Laboratory , 9700 South Cass Avenue, Lemont, Illinois 60439, United States.
Journal of the American Chemical Society
|January 1, 2016
概括
在全聚合物太阳能电池 (APSC) 中优化供体和受体聚合物的分子量对于性能至关重要. 通过平衡形态和电荷传输,中等分子重量,而不是最高的分子重量,产生最好的功率转换效率 (PCE).
科学领域:
- 材料科学
- 聚合物化学
- 可再生能源
背景情况:
- 全聚合物太阳能电池 (APSC) 为灵活和低成本的光伏应用提供了潜力.
- 光活性层的形态显著影响了APSC的性能.
- 控制聚合物特性,如分子重量,是优化形态的关键.
研究的目的:
- 研究数量平均分子重量 (Mn) 对混合膜形态和APSC光伏性能的影响.
- 了解供体 (PTPD3T) 和受体 (N2200) 聚合物的Mn变化如何影响相位分离和装置特性.
- 确定最大化APSC功率转换效率 (PCE) 的最佳Mn范围.
主要方法:
- 聚合聚合物的合成 (PTPD3T和N2200) 具有可调节的数值平均分子量 (Mn).
- 使用有系统变化的Mn的聚合物混合物制造APSC装置.
- 使用实验技术和粗粒度建模的混合膜形态的表征.
- 评估光伏性能,包括短路电流密度 (Jsc),填充系数 (FF) 和PCE.
主要成果:
- 增加供体和受体聚合物的Mn减少了域大小和增加了界面面积,促进了Jsc.
- 较高的Mn导致了混乱和电荷载体重组的增加,减少了FF.
- 与非最佳器件相比,具有中间Mns的优化光活性层在PCE中实现了两倍的增强.
- 一个二维的Mn优化策略确定了两种聚合物中介Mns的PCE"甜点".
结论:
- 对于优化APSC性能来说,提供者和接受者聚合物Mn的精确调整至关重要.
- 最佳的APSC性能是在中间Mns时实现的,这与发现表明最高的Mn是最好的相反.
- 这项研究提供了合成控制Mn的途径,并强调了它对APSC发展的重要性.
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