Theoretical study on the ferroelectric and light absorption properties of Li₂SbBiO₆ for harvesting visible light

Ferroelectric oxides with large bandgaps have restricted applications in photovoltaic and photocatalytic fields. Based on recent experiments with the ferroelectric compound, LiSbO₃, the stability and optoelectronic properties of a new ferroelectric compound, namely Li₂SbBiO₆, are investigated in this study. The calculated results demonstrate that Li₂SbBiO₆ satisfies the stability conditions of the elastic coefficients and phonon dynamics. Li₂SbBiO₆ maintains the ferroelectric polarization strength of LiSbO₃ and significantly reduces the bandgap, and thus has been explored for applications in photovoltaic and photocatalytic fields. Li₂SbBiO₆ is a new potential ferroelectric oxide for harvesting visible light owing to its suitable bandgap and a large hole-electron effective mass ratio.