The study of electronic and optical properties of perovskites CH3NH3PbCl3 and CH3NH3PbBr3 using first-principle

At present, Organic-inorganic hybrid methylammonium lead halide perovskites MAPbX 3 (MA= CH 3 NH 3 ; X = Cl, Br) have recently attract attention scientific researchers, as a promising candidate for photovoltaic and optoelectronic devices. We have studied the electronic structures and optical properties of perovskites CH 3 NH 3 PbBr 3 and CH 3 NH 3 PbCl 3 , using density functional theory (DFT). These physical properties are calculated by CASTEP code, such as the band structures, total density of states (TDOS), absorption coefficient, refractive index and optical conductivity. The analysis of band gap shows that these two perovskites are semiconducting materials. Calculated absorption coefficient of CH 3 NH 3 PbBr 3 and CH 3 NH 3 PbCl 3 shows an absorption peak around 3.87 eV and 2.04 eV, respectively. The above results provide good agreement with experimental work for optoelectronic properties of CH 3 NH 3 PbBr 3 and CH 3 NH 3 PbCl 3 materials.