The Critical Morphological Structures for Solvents Insensitive Processed Organic Solar Cells

The power conversion efficiencies (PCEs) of lab-sized organic solar cells (OSCs), usually processed from low-boiling-point and toxic solvents, have reached high values over 19%. However, the key limiting factor for green-processed OSCs is imperfect micro-morphology, which dominating a significant drop of the efficiency. Importantly, the final device parameters are always super sensitive to the solvents selected during solution-processed procedures. Herein, we obtain uniform PCEs over 18% in OSCs processed from a series of different solvents involving chloroform, chlorobenzene, toluene, (p-, o-, m-) Xylene by carefully designing of the OEG sides chains in non-fullerene small molecules. The specific intermolecular interactions formed in solution states dominate those uniform device parameters. Our inspiring strategy provides a broaden land view to develop large-area and high-efficiency OSCs from green solvents, figuring out the way towards industrial development of OSCs.