Improving the fill factor of N2200-based all polymer solar cells by introducing EPPDI as a solid additive

作者：Wang, Kai; Dong, Sheng^*; Zhang, Kai; Li, Zheng; Huang, Jun; Wang, Ming^*

来源：Organic Electronics: physics, materials, applications , 2021, 99: 106319.

DOI：10.1016/j.orgel.2021.106319

• All polymer solar cells
• Morphology control
• Solid additive
• Trap density
• Fill factor

A cheap and commercially available small molecule (namely EPPDI) is introduced to the active layer of N2200based all polymer solar cells as a solid additive. EPPDI at the optimal ratio can improve the D-A nano-scale morphology and reduce trap density of the active layer by filling morphological spaces. As a result, the photovoltaic performance of the resulting devices based on PF2:N2200 are increased from 6.28% to 7.03% with significantly enhanced fill factor. This work demonstrates a facile approach for improving the performance of all polymer solar cells.