Theoretical study on the ferroelectric and light absorption properties of Li 2 SbBiO 6 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, LiSbO, the stability and optoelectronic properties of a new ferroelectric compound, namely LiSbBiO, are investigated in this study. The calculated results demonstrate that LiSbBiO satisfies the stability conditions of the elastic coefficients and phonon dynamics. LiSbBiO maintains the ferroelectric polarization strength of LiSbO and significantly reduces the bandgap, and thus has been explored for applications in photovoltaic and photocatalytic fields. LiSbBiO is a new potential ferroelectric oxide for harvesting visible light owing to its suitable bandgap and a large hole-electron effective mass ratio.