Huiliang Sun, Bin Liu, Yunlong Ma, Jin-Woo Lee, Jie Yang, Junwei Wang, Yongchun Li, Bangbang Li, Kui Feng, Yongqiang Shi, Baohua Zhang, Dongxue Han, Hong Meng, Li Niu, Bumjoon J Kim, Qingdong Zheng, Xugang Guo
Narrow-bandgap n-type polymers with high electron mobility are urgently demanded for the development of all-polymer solar cells (all-PSCs). Here, two regioregular narrow-bandgap polymer acceptors, L15 and MBTI, with two electron-deficient segments are synthesized by copolymerizing two dibrominated fused-ring electron acceptors (FREA) with distannylated aromatic imide, respectively. Taking full advantage of the FREA and the imide, both polymer acceptors show narrow bandgap and high electron mobility. Benefiting from the more extended absorption, better backbone ordering, and higher electron mobility than those of its regiorandom analog, the L15-based all-PSC yields a high power conversion efficiency (PCE) of 15...
August 2, 2021: Advanced Materials