Theoretical study on the stability, ferroelectricity and photocatalytic properties of CaBiO₃

Materials with high ferroelectric polarization strength and sufficient absorption of visible light have unique advantages in photocatalysis. Based on the results of structure search, phonon frequency, and elasticity coefficient calculations, CaBiO₃ has a stable R3 polar structure. First-principles calculations indicate that R3-CaBiO₃ is a potentially efficient ferroelectric visible-light photocatalytic material for hydrogen production. CaBiO₃ under slight strain can maintain high ferroelectric polarization strength, strong visible light absorption capacity and small effective mass. CaBiO₃ under tensile strain has potentially ferroelectric photogeneration of hydrogen with a band edge position that crosses the redox potential of water. These results can expand the application of Bi-based materials in photocatalytic hydrogen production.