Ethanol‐Processable Polyfuran Derivative for Eco‐Friendly Fabrication of Organic Solar Cells Featuring Self‐Healing Function

Eco‐friendly fabrication of organic solar cells (OSCs) via alcohol or water is highly desired for their cost‐effective feature and benign profit for derived operators and ambient environment. Herein, a simple polyfuran derivative (PFO) that exhibits good solubility in ethanol/water solvent mixture is reported. Moreover, PFO displays broad optical absorption, high‐lying electronic energy level, and large hole mobility. The air‐ and ethanol‐processed PFO‐based OSCs deliver a fine efficiency of 2.25%. Even though only 45.24% of their initial efficiency is preserved for optimized devices after continuous illumination for 200 h in ambient atmosphere, the remained efficiency value of optimized devices can increase by 19.20% when undergoing intermittent illumination yet for the same light‐soaking time of 200 h. The self‐healing efficiency of devices suffering from discontinuous illumination is associated with the partial dissolution and reconstruction of hydrogen bonds in active layer. The results provide important guidelines for designing electroactive materials for safe and environmentally benign fabrication of OSCs with self‐sealing function.