Synthesis of V Doped Ca Bismuthate Nanoflakes for Photocatalytic Removal of Crystal Violet Dye

Background: Crystal Violet Dye (CV) can cause severe eye irritation and cancer due to its adsorption, ingestion, and inhalation effect. Therefore, CV in wastewater systems poses as a severe risk to human health and the environment. It is essential to remove CV before CV is discharged in the environment. Methods: Vanadium doped calcium bismuthate nanoflakes with the vanadium mass ratio of 1 wt%, 3 wt.%, 5 wt.%, and 10 wt.% have been synthesized by a simple hydrothermal route using sodium vanadate as a vanadium raw material. The obtained vanadium doped calcium bismuthate products were analyzed by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and solid diffuse reflection spectrum. Results: XRD patterns show that the vanadium in the doped nanoflakes exists as triclinic Bi3.5V1.2O8.25 and monoclinic Ca0.17V2O5 phases. SEM observations show that the morphology of the products is closely related to the vanadium mass ratio. The morphology changes from the nanoflakes to irregular nanoparticles is observed by increasing the vanadium mass ratio. The bandgap of the nanoflakes decreases to 1.46 eV and 1.01 eV when the doped vanadium mass ratio reaches 5 wt.% and 10 wt.%, respectively. The photocatalytic performance for the CV removal can be greatly enhanced using 5 wt.% and 10 wt.% vanadium doped calcium bismuthate nanoflakes, respectively. By increasing the irradiation time, vanadium mass ratio, and dosage of the nanoflakes, the photocatalytic activity for the CV removal can be improved. Conclusion: 10 wt.% vanadium doped calcium bismuthate nanoflakes have the best photocatalytic performance for CV removal. Vanadium-doped calcium bismuthate nanoflakes exhibit great application potential for the removal of organic pollutants.