Perovskite Film Fabrication by MAI Engineering via Non-Antisolvent Method

The scalable fabrication of high-efficiency perovskite solar cells (PSCs) remains a major challenge due to the limitations of conventional antisolvent methods. In this work, we introduce an antisolvent-free solvent engineering strategy using 2-methoxyethanol (2-ME) as the main processing solvent. Owing to its relatively low boiling point and high vapor pressure compared with conventional high-boiling polar aprotic solvents such as DMF, 2-ME facilitates rapid solvent evaporation and supersaturation during spin coating, enabling uniform film formation without antisolvent quenching. Unlike traditional processing routes, our approach avoids the need for antisolvent treatment and enables uniform film formation via controlled solvent volatilization. Furthermore, we systematically explore the effect of methylammonium iodide (MAI) concentration in the precursor solution on perovskite film quality and device performance. By fine-tuning the MAI content, we identify an optimal range that promotes balanced crystallization, suppresses non-perovskite phases, and enhances charge transport. The resulting perovskite films exhibit smooth surfaces, dense microstructures, and large grain sizes, contributing to improved device reproducibility and stability. Devices fabricated using the optimized composition deliver high-power conversion efficiencies with minimal performance variation across batches. 2-ME-based processing route combined with MAI modulation provides a viable pathway toward repeatable, scalable, and efficient perovskite photovoltaics. The strategy reported here not only simplifies the fabrication process but also offers insight into compositional control for next-generation solution-processed PSCs.