Theoretical investigations on the electronic and optical properties of Na-doped CH₃NH₃PbI₃ perovskite

¹ LRPSI, Faculty of Polydisciplinary, Sultan Moulay Slimane University, B.P 592, 23000, Beni Mellal, Morocco
² LIPCM, Faculty of Sciences and Technics, Sultan Moulay Slimane University, B.P 523, 23000, Beni Mellal, Morocco
³ Laboratory of Physics of Condensed Matter and Renewable Energy, Faculty of Sciences and Technology, Hassan II University of Casablanca, 146 Mohammedia, Casablanca, Morocco
⁴ Ecole Normale Superieure (ENS), Mohammed V University of Rabat, Morocco

^* Lhouceine Moulaoui: moulaoui.h.fpbm@gmail.com

Abstract

The development of important materials for photovoltaic applications is rapidly advancing, particularly in the field of perovskite materials. This study investigates the optical and electronic characteristics of CH ₃ NH ₃ Pb I₃ and analyzes the influence of doping in perovskite CH ₃ NH ₃ Pb I₃ with different concentrations of sodium ions Na⁺. In this study, we employed Density Functional Theory to assess the optical and electronic properties of both pure and Na⁺ ion-doped CH ₃ NH ₃ Pb I₃, with Na⁺ concentrations of 12.5 %, 25 %, and 37.5 %. The bandgap energy of pure CH 3 NH 3 Pb I3 rises from 1.205 eV to 1.573 eV as the concentration of Na⁺ ions increases from 0 % to 37.5 %, respectively. Doping with Na⁺ ions leads to an increase in the absorption coefficient of pristine CH 3 NH 3 Pb I₃ perovskite in both UV and visible ranges. Doping likewise affects the density of states, dielectric function, and the refractive index of CH ₃ NH ₃ Pb I₃ material. These findings offer vital insights into modulating the electronic and optical characteristics of CH ₃ NH ₃ Pb I₃ through Na⁺ ion doping.