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

ABSTRACT

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.