Ab-initio calculation of cubic and tetragonal phase of CsPbI₃ perovskite

A Study of The CsPbI₃ Two-Phase Electronic Structure Has Been Made Through Calculations Using the Density Functional Theory Method. Perovskite metal halide is used as a light-absorbing material on solar cells. This material has a high level of stability and an easy fabrication process. Also, the conversion efficiency has reached 10.1%. The two crystalline phases used are the cubic phase and the tetragonal phase. The electronic structure discussed includes the ribbon electronic curve, as well as the DOS (Density of States) curve, PDOS (Projected Density of States) curve. To find out the electronic structure, and optimization calculation is performed, namely variations in lattice constants, k-points, and cut-off energy. This optimization is done to get the structure with a minimum total energy so that its stability can be achieved. It is known that the bandgap energy value of the CsPbI₃ cubic is 1.44eV on the electronic and DOS curve curves. Whereas the band gap energy value of tetragonal CsPbI₃ is 0.6 eV on the electronic band curve and DOS as well. This shows that CsPbI₃ can be used for the perovskite semiconductor material. (paper)