First Principles Investigations of Physical Properties of the CsSnI3 Halide Perovskite for Thermophotovoltaics Devices

This work explores the first principles study of the mechanical, electronic, optical, thermodynamic, and thermoelectric properties of cubic-phase CsSnI₃ perovskites using the generalized gradient approximation (GGA). The electronic band gap and density of states analysis show the direct nature of band gap. All the calculated elastic constant parameters meet the mechanical stability criteria of cubic geometry. Moreover, optical behavior has been analyzed in terms of absorption coefficient, energy loss function, dielectric and refractive index. Finally, the electrical conductivity, power factor, see-beck coefficient, thermal and electrical conductivity explained what material response have with temperature. Calculations based on the optical and thermoelectric properties of the compounds’ fundamental principles offer experimentalists a new avenue for the possible use of these compounds in energy-renewable devices.