具有深度最高占成的分子轨道水平的宽带间隙聚合物使聚合物太阳能电池的效率达到14.2%
Sunsun Li1,2, Long Ye3, Wenchao Zhao1,2
1State Key Laboratory of Polymer Physics and Chemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.
Journal of the American Chemical Society
|May 9, 2018
概括
研究人员开发了一种新的宽带隙聚合物,用于无烯聚合物太阳能电池,实现高效率和低能耗. 侧链工程通过增强分子包装和电荷传输提高了性能.
科学领域:
- 材料科学
- 有机电子
- 太阳能发电
背景情况:
- 具有深度HOMO水平的宽带间隙 (WBG) 供体聚合物对于高效的无烯聚合物太阳能电池 (PSC) 是至关重要的.
- 实现低光子能量损失 (Eloss) 和广泛的光谱响应需要精心的分子设计.
研究的目的:
- 设计和合成一种基于新型二甲单元 (DTBDT-EF) 的新型WBG供体聚合物.
- 研究分子设计和侧链工程对PSC性能的影响.
- 通过优化形态和电荷传输来实现高功率转换效率 (PCE).
主要方法:
- 合成一种新的二甲单元 (DTBDT-EF) 和相应的聚合物 (PDTB-EF-T).
- 对聚合物的特性进行系统的研究,包括HOMO水平,氧化潜力和聚合效应.
- 侧链工程优化分子包装和链间相互作用.
- 使用开发的聚合物和小分子接受器 (IT-4F) 制造和描述倒置PSC装置.
- 使用X射线光辐射光谱和横截面传递电子显微镜分析混合物形态.
主要成果:
- 该PDTB-EF-T聚合物表现出一个深度的HOMO水平 (约. -5.5 eV) 由于协同的电子吸收效应.
- 实现了0.90V的高开通电压 (Voc) 和0.62 eV的低E损失.
- 侧链工程,特别是使用线性十替代物 (P2),增强链间 π-π 相互作用,孔移动性和电荷传输.
- 优化的P2:IT-4F混合物显示了面向相分离和垂直相分布.
- 基于P2的反向PSC实现了高的PCE14.2%,剩余填充系数 (FF) 为0.76.
结论:
- 新的DTBDT-EF单元对于开发高性能WBG供体聚合物非常有前途.
- 分子设计和侧链工程是调整聚合物特性和设备性能的有效策略.
- 优化形态和电荷传输是实现无烯PSC高PCE和FF的关键.
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