Intramolecular Chloro-Sulfur Interaction and Asymmetric Side-Chain Isomerization to Balance Crystallinity and Miscibility in All-Small-Molecule Solar Cells

作者：Gao, Wei; Jiang, Mengyun; Wu, Ziang; Fan, Baobing; Jiang, Wenlin; Cai, Ning; Xie, Hua; Lin, Francis R.; Luo, Jingdong; An, Qiaoshi^*; Woo, Han Young^*; Jen, Alex K. -Y.^*

来源：Angewandte Chemie - International Edition, 2022, 61(33): e202205168.

DOI：10.1002/anie.202205168

• Crystallinity
• Intramolecular Interaction
• Miscibility
• Small Molecule Donors
• Solar Cells

Intramolecular Cl-S non-covalent interaction is introduced to modify molecular backbone of a benzodithiophene terthiophene rhodamine (BTR) benchmark structure, helping planarize and rigidify the molecular framework for improving charge transport. Theoretical simulations and temperature-variable NMR experiments clearly validate the existence of Cl-S non-covalent interaction in two designed chlorinated donors and explain its important role in enhancing planarity and rigidity of the molecules for enhancing their crystallinity. The asymmetric isomerization of side-chains further optimizes the molecular orientation and surface energy to strike a balance between its crystallinity and miscibility. This carefully manipulated molecular design helps result in increased carrier mobility and suppressed charge recombination to obtain simultaneously enhanced short-circuit current (J(sc)) and fill factor (FF) and a very high efficiency of 15.73 % in binary all-small-molecule organic solar cells.

• 单位
  武汉大学; 北京理工大学; 广东工业大学