Importance of structural hinderance in performance-stability equilibrium of organic photovoltaics

作者：Fan, Baobing; Gao, Wei; Wu, Xuanhao; Xia, Xinxin; Wu, Yue; Lin, Francis R.; Fan, Qunping; Lu, Xinhui; Li, Wen Jung; Ma, Wei; Jen, Alex K. -Y.^*

来源：Nature Communications, 2022, 13(1): 5946.

DOI：10.1038/s41467-022-33754-3

• SOLAR-CELLS
• EFFICIENCY

Power conversion efficiency and long-term stability are two critical metrics for evaluating the commercial potential of organic photovoltaics. Although the field has witnessed a rapid progress of efficiency towards 19%, the intrinsic trade-off between efficiency and stability is still a challenging issue for bulk-heterojunction cells due to the very delicate crystallization dynamics of organic species. Herein, we developed a class of non-fullerene acceptors with varied side groups as an alternative to aliphatic chains. Among them, the acceptors with conjugated side groups show larger side-group torsion and more twisted backbone, however, they can deliver an efficiency as high as 18.3% in xylene-processed cells, which is among the highest values reported for non-halogenated solvent processed cells. Meanwhile, decent thermal/photo stability is realized for these acceptors containing conjugated side groups. Through the investigation of the geometry-performance-stability relationship, we highlight the importance of side-group steric hinderance of acceptors in achieving combined high-performance, stable, and eco-friendly organic photovoltaics. @@@ The intrinsic trade-off between efficiency and stability is a challenging issue for organic photovoltaics. Here, the authors develop non-fullerene acceptors with tailored side-group hindrance and backbone planarity and realise efficiency of 18.3% and good stability for xylene-processed solar cells

• 单位
  西安交通大学