The Combination of S⋯N and S⋯Cl Noncovalently Conformational Locks for Constructing High‐Planarity and Low‐Cost Nonfused‐Ring Electron Acceptors†

By employing thiazole and 4-chlorothiazole as the A′ units, two A-D-A′-D-A type nonfused-ring electron acceptors (NFREAs) Tz-H and Tz-Cl were designed and synthesized. Replacing thiazole in Tz-H with 4-chlorothiazole can not only remarkably shorten the synthetic route through C-H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz-Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz-H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low-cost and high-performance NFREAs. This article is protected by copyright. All rights reserved. Supporting Information Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.