Hybrid Two-Step Inkjet-Printed Perovskite Solar Cells

Abstract

Perovskite photovoltaics are on their way to commercialization, but crucial advancements are still required to realize scalable and reliable fabrication processes Concerning solution processing of perovskite top solar cells, the hybrid two-step process offers an auspicious combination of good thin-film formation control, even on textures, and high power conversion efficiencies (PCEs). Herein, a scalable fabrication process that consists of a hybrid two-step process and combines evaporated PbI2 with inkjet-printed organic precursor materials is addressed. It is shown that optimizing the printing parameters enables high PCEs, high reproducibility, and the potential for conformal growth on textured silicon. The perovskite films are free of macroscopic drying effects and omit the use of toxic solvents. To achieve optimal conversion, the morphology of the PbI2 thin film and the selected resolution in the printing process are decisive. To facilitate intermixing and enable stoichiometry, a dimethyl sulfoxide vapor treatment is introduced to increase the PbI2 porosity. Reproducible PCEs are demonstrated with champion devices showing 18.2% which are on par with spin-coated counterparts. In the results, it is demonstrated that the hybrid two-step process with an inkjet-printed second step is a promising scalable process for reliable and high-quality perovskite deposition even on texture, thereby paving the path toward industrialization.