Degradation Behavior of Methylammonium Lead Iodide (CH3NH3PbI3) Perovskite Film in Ambient Atmosphere and Device

Methylammonium lead iodide (MAPbI3) has attracted more attention due to its promising features appropriate for photovoltaic application, although the material still struggles with instability towards environmental factors. Understanding the degradation mechanism in this material is of immense importance in increasing material stability. This work investigated the degradation process of MAPbI3 perovskite in an ambient atmosphere with controlled humidity for twelve days at three days interval. The crystallographic structural changes were observed by X-Ray Diffraction (XRD) and analyzed with the support of the Rietveld refinement method. The result shows transition from MAPbI3 Tetragonal to PbI2 trigonal by removal of CH3NH3I, which is evident in X-ray photoelectron spectroscopy (XPS) elemental analysis. UV–Vis spectroscopy and photoluminescence show changes in the band-gap. Scanning electron microscopy (SEM) observes morphological changes and impedance spectroscopy studies electrical behavior. Our study explains the MAPbI3 structural, optical, morphological, thermal, and electrical behavior changes during degradation in different studies; it is beneficial for a deeper understanding of the degradation mechanism.