A novel Bi-based oxybromide SrBiO2Br: Synthesis, optical property and photocatalytic activity

A novel Bi-based photocatalyst SrBiO2Br with layered structure was successfully synthesized via a solid state reaction method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectra (DRS). SrBiO2Br has an indirect-transition optical band-gap of 2.58 eV. Density functional calculations revealed that conduction band (CB) were composed of the Bi 6p and Br 4s orbitals, and valence band (VB) were occupied by Br 4p and O 2p. The photodecomposition of rhodamine-B (RhB) experiments demonstrated SrBiO2Br can be used as photocatalysts under ultraviolet (UV) light and visible light irradiation (λ > 400 nm). The results revealed that SrBiO2Br calcinated at 700 °C exhibited the highest photocatalytic activity among the obtained SrBiO2Br samples.