A computational study of alkali (Na, K, Cs) doped methylammonium lead iodide perovskite

Abstract

Methylammonium Lead Iodide (MAPbI3) is bellwether in the field of photovoltaics due to its remarkable optoelectronic properties. However, the instability of MAPbI3 hinders its commercial scale applications. To address this issue, we have utilized the method of compositional engineering by doping A-site of MAPbI3 with alkali metals (Na, K, Cs) availing the first principle study within the framework of density functional theory. To realize the band structure, geometry is initially optimized using GGA-PBE, GGA-PBESOL and GGA-PW91 exchange correlation functionals and then GGA + SOC technique is applied to draw the comparison for better insight of the electronic structure. Later we explored the structural, electronic, optical, elastic, and thermodynamic properties of alkali doped MAPbI3. The results manifest improvement in the phase stability, thermodynamic stability and optical absorption of MAPbI3 after being doped with Na, K and Cs. These properties can provide research ideas for ensuing research in A-site doped studies of MAPbI3.