Affiliation:
1. State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
2. College of Chemistry and Pharmaceutical Engineering Huanghuai University Zhumadian Henan 463000 P. R. China
3. Yaoshan Laboratory Pingdingshan University Pingdingshan Henan 467000 P. R. China
4. Petrochemical Research Institute of PetroChina Company Limited Beijing 102206 P. R. China
Abstract
AbstractThe dimerization of small molecule acceptors (SMAs) holds significant potential by combining the advantages of both SMAs and polymer acceptors in realizing high power conversion efficiency (PCE) and operational stability in organic solar cells (OSCs). However, advancements in the selection and innovation of dimeric linkers are still challenging in enhancing their performance. In this study, three new dimeric acceptors, namely DY‐Ar‐4, DY‐Ar‐5, and DY‐Ar‐6 are synthesized, by linking two Y‐series SMA subunits via an “end‐to‐end” strategy using flexible spacers (octyl, decyl, and dodecyl, respectively). The influence of spacer lengths on device performance is systematically investigated. The results indicate that DY‐Ar‐5 exhibits more compact and ordered packing, leading to an optimal morphology. OSCs based on PM6: DY‐Ar‐5 achieves a maximum PCE of 15.76%, attributes to enhance and balance carrier mobility, and reduce carrier recombination. This dimerization strategy using suitable non‐conjugated linking units provides a rational principle for designing high‐performance non‐fullerene acceptors.
Funder
National Natural Science Foundation of China
Fundamental Research Funds for the Central Universities