Sustainable Green Solvents for Lead Halide Perovskites

Abstract Lead halide perovskites have revolutionized the field of optoelectronics and attracted worldwide attention due to their outstanding semiconducting characteristics. Meanwhile, solution processability and printability of the perovskite allow the commercialization of perovskite solar cells (PSCs) profitable. However, deposition of the perovskite films usually uses polar aprotic solvents. The popular antisolvents are aromatics or aromatic halogenated hydrocarbons. All of them have a high risk of toxicity and flammability. To reduce the adverse effects on the environment and operators and enhance the sustainability of perovskite technologies, researchers have made lots of efforts to study sustainable green solvents. Herein, the selection criteria of green solvents are surveyed. Methods of solubility prediction of precursor solvents are comprehensively discussed from the perspectives of polarity and Lewis acid–base chemistry. The significance of antisolvent polarity and boiling point is emphasized. Research advances in green solvents are summarized. Finally, this review presents in‐depth insights into green‐solvent‐processable perovskites and highlights research directions for perovskite modules in the future. It lays a good foundation for the commercialization and sustainable development of PSCs.