Manipulating Polymer Backbone Configuration Via Halogenated Asymmetric End-Group Enables Over 18% Efficiency All-Polymer Solar Cells.

High-performance all-polymer solar cells (all-PSCs) deeply rely on the joint contributions of desirable optical absorption, adaptive energy level and appropriate morphology. Herein, two structural analogous polymerized small molecule acceptors (PSMAs), PYFCl-T and PYF&PYCl-T, were synthesized, and then incorporated into the PM6:PY-IT binary blends to construct ternary all-PSCs. Due to the superior compatibility of PY-IT and PYFCl-T, the ternary all-PSC based on PM6:PY-IT:PYFCl-T with 10 wt% PYFCl-T, presented higher and more balanced charge mobilities, suppressed charge recombination, and faster charge transfer kinetics, resulting in an outstanding power conversion efficiency (PCE) of 18.12% with the enhanced J sc and FF, which is much higher than that (PCE of 16.09%) of the binary all-PSCs based on PM6:PY-IT. Besides, the ternary all-PSCs also exhibited improved photostability. The conspicuous performance enhancement principally should give the credit to the miscibility-driven phase optimization of the donor and acceptor. These findings highlight the significance of polymer backbone configuration modulation of PSMAs in morphology optimization toward boosting the device properties of all-PSCs. This article is protected by copyright. All rights reserved.