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

Abstract

Comprehensive Summary 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.

Designing thickness-insensitive cathode interlayers via constructing noncovalently conformational locks for highly efficient non-fullerene organic solar cells

“…Therefore, we can conclude that the decrease in atomic spacing conrms the presence of strong intramolecular S/H bonds in PF-TT and PF-BDT molecules to lock the neighboring aromatic ring structures. [36][37][38] However, rotations or distortions of the adjacent units occur, and atomic spacing in the neighboring aromatic rings increases owing to the lack of such conformation-locking features for the PF-F molecule. Additionally, the electrostatic potential (ESP) distribution is simulated, as shown in Fig.…”

Low-Cost Nonfused-Ring Electron Acceptors Enabled by Noncovalent Conformational Locks

“…Copyright 2021 Wiley-VCH GmbH. (g, h) Reproduced with permission from ref . Copyright 2023 SIOC, CAS, Shanghai, & Wiley-VCH GmbH.…”

Enhancing Photovoltaic Performance of Nonfused‐Ring Electron Acceptors via Asymmetric End‐Group Engineering and Noncovalently Conformational Locks

“…To address this issue, large steric hindrance of side‐chains and weak intramolecular interactions (also known as noncovalently conformational locks, NoCLs) are introduced in molecular design to lock‐in the conformation, thereby eliminating conformational isomers and achieving a highly coplanar π‐conjugated backbones. [ 36‐44 ] Recently, we reported a PhO4T‐series of symmetric NFREAs, demonstrating higher figure‐of‐merit values than those of FREAs, due to their simple structures and concise synthesis routes. [ 45 ] However, the PCEs of NFREAs have still lagged far behind those of FREAs.…”