Doping effect of iodine on electronic and optical properties of perovskite CsPbBr3 compound for photovoltaic applications: Ab initio calculations

•The CsPbBr3 perovskite compound are studied using several concentration of Iodine.•The electronic and optical properties of this compound are investigated using ab initio calculation.•For different concentration of Iodine the gap value decreased from 2.16 eV to 1.43 eV.•The peak of absorption observed at the visible range for 33 % of Iodine doping. The halide perovskite CsPbBr3 compound have a huge interest this last years as a promising perovskite for photovoltaic application due to their properties, as known in photovoltaic field the gap value is a major element who influences on the efficiency of panels. In this work, the electronic and optical properties of this compound are investigated using ab initio calculation. In addition, we applied a different percentage of Iodine doping in CsPbBr3-x (x = 0%, 22 % and 33 % of I) to reduce the gap value. As a result the gap value decreased from 2.31 eV (0%) to 1.58 eV (33 %) of I-doping. Also, we had a peak at the visible range for the absorption showing at 33 % of I-doping.