Effect of 2-propanol Immersing on Organohalide Perovskite Layer in Perovskite Solar Cells Fabricated by Two-step Method

Abstract

In the 2-step method of CH₃NH₃PbI₃, the CH₃NH₃PbI₃ layer is converted using methylammonium iodide (MAI) after coating a PbI₂ layer. Although the use of dimethyl sulfoxide (DMSO) is reported to enhance the crystal quality of perovskite layer, we could not achieve the similar result. We studied the relationship between the layer properties of PbI₂ and the DMSO content in solvent. In addition, we checked the layer properties of perovskite layer and the photovoltaic performance of the cells with the above perovskite active layers. We found the immerse process of PbI₂ in 2-propanol influences the reconstruction of PbI₂ morphology and the diffusion process of MAI depends on the PbI₂ morphology.