Electronic structure of nontoxic-inorganic perovskite: CsMgBr3 using DFT calculation

Abstract We introduce the new perovskite material, CsMgBr 3 , which is composed of pure nontoxic-inorganic elements by substitution of Cs + and Mg 2+ instead of CH 3 NH 3+ and Pb 2+ in a well-known CH 3 NH 3 PbI 3 perovskite. This study was extracted by using the density functional theory (DFT) with Hybrid functional of Heyd-Scuseria-Ernzerhof (HSE) and the generalized gradient approximation (GGA). The band structures of three diferent phases of CsMgBr 3 including α, β and γ- phases reveal that the band gaps of these material are in the ultraviolet region (UV). We found that only γ-phase is the direct band gap material, while others are the indirect band gap materials. The results of efective masses of these compounds show that the mobility of hole is lower than that of electron and the α-phase has the highest hole and electron mobility.