A Universal Fluorinated Polymer Acceptor Enables All-Polymer Solar Cells with >15% Efficiency
Feng Peng, Kang An, Wenkai Zhong, Zhenye Li, Lei Ying, Ning Li, Zhenqiang Huang, Chunguang Zhu, Baobing Fan, Fei Huang, Yong Cao
Abstract
While great progress has been achieved in all-polymer solar cells (all-PSCs), the efficiency of all-PSCs is primarily limited by polymer acceptors that lack a high extinction coefficient, high electron mobility, and good compatibility with polymer donors. Here we designed and developed a polymer acceptor PFA1 based on a non-fullerene acceptor framework with a fluorine substituent on the 1,1-dicyanomethylene-3-indanone unit. In combination with an electron-donating polymer, PTzBI-oF, the blend film presents an extended and intensified absorption profile, enhanced electron mobility, and favorable film morphology. The optimized all-PSCs exhibit a remarkably high efficiency of 15.11%, which is, to the best of our knowledge, the highest performance yet reported for an all-PSC. Of particular importance is the applicability of PFA1 as a universal polymer acceptor with a range of polymer donors to achieve impressively high efficiencies. These properties enable a new molecular design strategy for the construction of polymer acceptors toward applications in high-performance all-PSCs.