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

Highlights: • SrBiO₂Br was first explored as a novel photocatalyst. • SrBiO₂Br has been successfully synthesized by a solid state reaction. • We systematically synthesized SrBiO₂Br in different temperature. • SrBiO₂Br calcinated at 700 °C exhibited the highest photocatalytic activity. - Abstract: 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