Perovskite films prepared by solvent volatilization via DMSO-based intermediate phase for photovoltaics

Perovskite films are commonly prepared by the anti-solvent method. However, the method is not suitable for large scale production. In this work, we develop a perovskite film fabrication technique based on dimethylsulphoxide (DMSO) using volatilization solvents. The perovskite solute is modified by DMSO, and the volatile solvents of 2-methoxyethanol (2-ME), and methylamine ethanol 33 wt% in ethanol (MA ethanol) are designed to replace the traditional anti-solvent method due to the high vapor pressures of the solvents. Perovskite films are obtained by thermal treatment via phase transition from DMSO-based intermediate films. The perovskite film fabrications are optimized by the amount of DMSO, annealing temperatures, and perovskite precursor concentrations. The films with large grain sizes, uniform structure, and even surface are achieved. The photovoltaic properties of the perovskite films are studied. The films prepared by our method show high reproducibility, facile operation, and significant potential in large scale production for practical applications. Therefore, the method developed in this work paves the way for the commercialization of the perovskite solar cells (PSCs) in terms of repeatability, simplification, and large-scale production.