Efficient and Stable Ternary Organic Solar Cells Using Liquid Crystal Small Molecules with Multiple Synergies

A liquid crystal small molecule donor BTR-Cl, which has strong self-assembly and crystallinity, is used as the third component to construct nonfullerenes ternary solar cells together with a broad-band donor polymer D18-Cl and a low-band acceptor N3. The introduction of BTR-Cl enhances the morphology, exciton dissociation, and charge mobility of the ternary blends, improves the short-circuit current density and fill factor, and results in an efficiency of up to 17.92%. Further results show that BTR-Cl acts as an energy level mediator, fluorescence resonance energy transfer and charge transfer intermediary, and morphology modifier in ternary blends. They work synergistically in ternary blends to optimize the electrical and morphological properties, resulting in enhanced photovoltaic performance and improved stability and detection performance. It brings vitality to the field of organic solar cells (OSCs) and organic photodetectors (OPDs) research.