Oxygen-vacancy-rich BiOBr photocatalytic material as well as preparation method and application thereof

The invention discloses an oxygen-vacancy-rich BiOBr photocatalytic material as well as a preparation method and application thereof. The preparation method of the photocatalytic material comprises the following steps: mixing polyethylene glycol and water to obtain a mixed solvent; the preparation method comprises the following steps: dissolving bismuth salt, bromine salt and lignin in a mixed solvent to obtain reaction liquid, uniformly mixing the reaction liquid, transferring the reaction liquid into a reaction kettle, and carrying out hydrothermal reaction to prepare a target product. According to the invention, polyethylene glycol is used as a reducing agent and is matched with lignin, oxygen vacancies can be simultaneously generated on the surface of the crystal and in the crystal through a hydrothermal reaction, and the prepared product has good stability. The photocatalytic material prepared by the invention can efficiently and simultaneously oxidize and reduce rhodamine B and Cr (VI) in water, and can