确定高性能全聚合物太阳能电池中聚合物分子重量的作用:其对聚合物聚合和相位分离的影响
Hyunbum Kang1, Mohammad Afsar Uddin, Changyeon Lee
1Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 335 Gwahangno, Yuseong, Daejeon 305-701, Korea.
Journal of the American Chemical Society
|January 22, 2015
概括
这项研究为全聚合物太阳能电池合成了具有不同分子量的合聚合物. 高分子量聚合物提高了性能,实现了超过5%的功率转换效率.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 有机电子 有机电子
背景情况:
- 分子重量极大地影响结合聚合物的特性,如电行为,形态和可溶性.
- 合聚合物是有机电子设备的关键组件,包括全聚合物太阳能电池 (全PSC).
研究的目的:
- 合成和研究一系列具有不同数值平均分子量 (Mn) 的半晶体聚[(2,5-bis(2-hexyldecyloxy) phenylene) -alt-(5,6-difluoro-4,7-di(thiophen-2-yl) benzo[c][1,2,5]thiadiazole) ] (PPDT2FBT) 聚合物.
- 评估PPDT2FBT分子重量对所有PSC的结构,形态,电气和光伏性能的影响,使用P(NDI2OD-T2) 接受器.
- 了解分子重量调整如何影响所有PSC中的聚合物聚合和批量异质连接形态.
主要方法:
- 合成具有受控数值平均分子量 (M(n) 的PPDT2FBT聚合物: 12公斤/mol (PPDT2FBT(L)),24公斤/mol (PPDT2FBT(M) 和40公斤/mol (PPDT2FBT(H)).
- 使用PPDT2FBT作为电子捐赠体和P(NDI2OD-T2) 作为电子接受体的全聚合物太阳能电池 (全PSC) 的制造和表征.
- 使用牧场事件X射线散射 (GIXS) 和共振软X射线散射 (RSoXS) 的形态和结构分析.
- 测量电特性,包括孔和电子流动性.
- 光伏性能评估以确定功率转换效率 (PCE).
主要成果:
- 调整PPDT2FBT的M(n) 显著改变了聚合物聚合的行为和所有PSC的大型异质连接形态.
- 较高的M(n) PPDT2FBT(H) 在混合膜中促进了有利的"面对面"导向,抑制了过度的晶体域生长,并增强了与P(NDI2OD-T2) 接受器的分子混合.
- 使用PPDT2FBT (H) 的优化全PSC与使用PPDT2FBT (L) 的设备相比,显示出明显更高的孔和电子流动性.
- 优化的全PSC实现了超过5%的功率转换效率,这对于这个类型的太阳能电池来说是一个显著的表现.
结论:
- PPDT2FBT的数值平均分子量是控制形态和优化全聚合物太阳能电池性能的一个关键参数.
- 实现分子重量的平衡对于有利的薄膜形态,分子混合和高效的电荷传输至关重要.
- 该研究表明,通过精确控制捐赠聚合物分子重量,实现高性能全PSC的途径,达到5%以上的效率.
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