Highly stable MAPbI₃ microcrystals: a single precursor derived from low-grade PbI₂ using sono-chemical method for economical and efficient perovskite solar cells

The remarkable performance of organometallic lead halide perovskites in solar cell technology has drawn attention due to their intriguing properties. Commercialization of perovskite solar cell (PSC) technology is hampered by high-cost device fabrication techniques and inadequate stability under ambient conditions. In this study, we used low-grade PbI₂ to make highly stable Methylammonium lead Iodide (MAPbI₃) powder via sono-chemical method, in order to reduce the cost of the PSCs. The sono-chemical method is used to synthesize MAPbI₃ microcrystals because of its significant advantages, including morphological control and educt dissolution support. The tetragonal phase of the synthesized perovskite (MAPbI₃) powder was confirmed using PXRD measurement. The synthesized MAPbI₃ powder was then subjected to series of analysis, including UV–Vis–NIR absorption, PL Emission, FTIR and TGA. The FESEM and TEM analyses reveal that the size of synthesized MAPbI₃ microcrystals is in the range of 0.3–2 μm. The optical and photovoltaic properties of conventional solution-based films and powder-based recrystallization films were studied and compared their performance in the carbon-based perovskite solar cell (C-PSC). The powder-based solar cell exhibits slightly higher power conversion efficiency (10.1%) than the device fabricated by conventional solution-based approach (9.5% for high-grade PbI₂ + MAI and 6.8% for low-grade PbI₂ + MAI). The enhanced photovoltaic characteristics of the recrystallization-based devices were attributed to the homogeneous perovskite film with large grain size and high crystalline properties.