Surface interface structural studies of CH3NH3PbI3 thin films using synchrotron source X-ray diffraction for solar cell application

Abstract

Presently, Organic-inorganic hybrid-based Perovskite material research is gaining attraction in the solar energy field, with efficiencies reaching upwards of 25.7 percent. Even though various efforts have been made to increase the shelf life and to reduce the degradation of perovskite material, still several complicated processes are required to achieve better structural properties and chemical stability. In this paper, Perovskite material is prepared with an optimized molar ratio (PbI2/MAI) = 1.0/1.0, this combination of PbI2 (Lead Iodide) and MAI (Methyl Ammonium Iodide) provides the best inter-diffusion (as noticed) and structural ordering. The above-stated ratio of PbI2 (Lead Iodide) and MAI (Methyl Ammonium Iodide) is suggested to be one of the best molar ratios in the literature. Except of this, there is still a lack of studies found in literature like the optimized structure properties for better device performance, as well as the thickness dependence structural properties variation and the role of inter-diffusion of MAI and PbI2. The present studies focused on the Synchrotron source-based X-ray Diffraction measurements to understand the structural properties of such films at the three different angles of incidence supported by SEM and AFM data. Finally, the present study of this perovskite material paves a way to understand the diffusion of MAI into the PbI2 along with the film thickness of 350 ± 50 nm of the Perovskite layer for one molar ratio in detail. Last but not the least, together with the Synchrotron source-based GIXRD measurements SEM, AFM, and UV–Vis spectroscopy helped to understand the distribution of PbI2 after MAI gets diffused into it and a little amount of un-used PbI2 leftover along with the entire film after the PbI2 and MAI Interaction.