Highly Stable FA_xMA_(1-x)PbI_(3-x)Br_x–2P Precursor for Crystalizing High-Quality, Large-Area Perovskite Film in anAmbient Atmosphere

摘要

Perovskite solar cells (PSCs) are one of the highly promising new-generationphotovoltaic technologies. One of the remaining challenges for commercializingPSCs is to prepare high-quality, large-area perovskite films in an ambient atmospherereproducibly using less toxic materials. Herein, a nonvolatile, less toxicsubstance, 2-pyrrolidinone (2P), is used as a complexant solvent for the perovskiteprecursor solution. Combining this with a newly developed spin-assistedsolvent extraction (SASE) crystallization method, a high-quality perovskite film isprepared in air reproducibly. The nonvolatile nature of 2P and the formation ofMAI–PbI_2–2P adduct widen the time window for antisolvent engineering, andSASE enhances the solvent exchange rate of the precursor film to form a highqualityperovskite film in air. An inverted cell (based on the postsolvent-treatedperovskite absorber) exhibits a power conversion efficiency of more than 18%.This film preparation method is feasible for depositing a high-quality mixedcationor mixed-cation, mixed-halide perovskite film on both PEDOT:PSS andTiO_2 surfaces to fabricate inverted and regular PSCs, respectively, to achieveefficiencies of more than 16%. More importantly, high-quality, large-area MAPbI3film is prepared reproducibly in air for fabricating perovskite submodules toachieve an efficiency of 14% (verified at 13.04% after the cell is packed forefficiency evaluation).