External Electric Field Induced Atomic Charge Migration and Surface Degradation of CsPbI3: A Reactive Molecular Dynamics Simulation based study

Abstract

Cesium lead iodide, CsPbI3, is a promising material for solar cell manufacturing; nonetheless, it has numerous mechanical stability issues. Furthermore, due to low spatiotemporal resolution in experimental tests, the effect of several types of external loads, such as temperature and electric field-induced stresses, on the degradation mechanism of perovskite materials is poorly known. In this study, the electrical field-induced surface degradation mechanism of α, β, γ-CsPbI3 phases is simulated using advanced reactive molecular dynamics simulation. Our simulation results provide information about the rupture of atomic level unit cells and the subsequent erosion of materials from the surface (surface degradation) under the effect of an external electric field. The surface degradation is caused by electric field-induced stresses on Cs, Pb, and I atoms. The forces acting on the anion I are stronger than those acting on the cation Cs and the Pb atom. Atomic charge migration is strongly impacted by the magnitude of the electric field and the temperature of the system. Prior to surface degradation, charge migration occurs under a modest electric field. We investigated atomic charge migrations across various atoms and their unit cells. We anticipate that our findings will help researchers better understand the stability of perovskite materials under electric field and temperature-induced stress.