Time-resolved photoluminescence studies on localization effects in orthorhombic phase of CH3NH3PbI3 perovskite thin film

We present the localization effects in orthorhombic phase of CH3NH3PbI3 perovskite materials by temperature-dependent photoluminescence and time-resolved photoluminescence. Our investigations indicate that the tetragonal inclusions in the orthorhombic phase of MAPbI3 at low temperature are the main reason for the formation of localization states with a depth of about 22.3 meV. The coexistence of the tetragonal and orthorhombic phases also results in an abnormal behavior of luminescence intensity from 12 to 80 K. The detailed understanding of luminescence characteristics upon the orthorhombic phase in MAPbI3 at low temperature can expand ideally the application fields of perovskite materials.