Structural, Electronic and Optical Properties of CsPbBr3 and CH3NH3PbBr3: First-Principles Modeling

Organic-inorganic hybrid perovskites have recently attracted attention as important materials for their potential ability as solar cells, light-emitting devices, and photonic applications. In this study, we focused on the investigation within density functional theory of structural, electronic, and optical properties of temperature-dependent phases of CsPbBr
3
and CH
3
NH
3
PbBr
3
perovskites. Changes in the properties of the studied crystal phases were analyzed by using different approximations for exchange-correlation functional. The electronic properties of perovskites have been investigated by estimated their changes upon applying spin-orbit coupling. The electronic properties demonstrate that all crystal phases CsPbBr
3
and CH
3
NH
3
PbBr
3
are semiconductors with direct bandgaps. The optical properties exhibit that investigated perovskites have good photon absorption ability due to their value of bandgaps. This theoretical result demonstrates the possibility of using CsPbBr
3
and CH
3
NH
3
PbBr
3
in a wide temperature range.