Synthesis and Characterization of Methylammonium Strontium Bromide Hybrid Perovskite

In this paper, we synthesized Sr-containing hybrid perovskite, methylammonium strontium bromide (MASrBr₃), and investigated its properties. We report the preparation of MASrBr₃ thin films and studied the effects of annealing temperature, annealing time, and precursor solution concentration on crystal growth using X-ray diffraction (XRD) and UV-vis spectroscopy. The composition and crystalline nature of the MASrBr₃ thin film were further confirmed using XRD and SEM-EDX. We explored the stability of the MASrBr₃ thin films in three solvents and the electrochemical stability of MASrBr₃ in an ionic liquid (IL), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. From this study, we observed that MASrBr₃ was stable from -1.75 to 0.35 V vs Fc/Fc⁺. Lastly, we determined that the MASrBr₃ thin films possess an indirect band gap of 4.52 eV, which is corroborated by density functional theory (DFT) calculations. Taken together, these results indicate that the synthesized MASrBr₃ perovskite is viable for future high-bandgap device applications.