Solvation properties of PbI₂ and MAPbI₃ in γ-Butyrolactone

Lead-halide perovskites represents the most studied family of materials in the last decade, due to their very peculiar optoelectronic properties that have allowed their rapid application in widespread devices. Experimentally, it was shown that the synthesis process of perovskites is crucial for their morphology and growth, and thus for the final quality of the devices. Therefore, understanding the growth and nucleation of perovskites in solution is of tremendous interest for higher efficiency and performance. Highly polar solvents or their mixtures are generally employed in the perovskite synthesis. Therefore, it is necessary to find out the coordinating ability of solvents to PbI₂ and MAPbI₃ so that we can choose the solvent combination for the fast blade coating of perovskites. Recently, we employed a fine-tuned theoretical framework, combining state-of-the-art computational methods, to investigate the interaction mechanisms and optical properties of PbI₂ within the low coordinative γ-Butyrolactone (GBL) solvent. We will present and discuss the coordination ability of GBL to PbI₂ and its correlation to the experimental UV-vis absorption spectrum. Using an extended approach, we will discuss new results of the structural and dynamics properties of PbCl₂ and MAPbI₃ in solution.