Biosynthesis of BiVO₄nanorods using Callistemon viminalis extracts: Photocatalytic degradation of methylene blue

This contribution reports on the biosynthesis of the n-type Bismuth vanadate (BiVO₄) nanorods prepared via the use of aqueous extracts of Callistemon viminalis as an effective chelating agent. To ascertain the formation of crystalline and pure BiVO₄nanorods, various surface & interface characterization were performed on annealed BiVO₄powders. X-Ray Diffraction analysis showed that the BiVO₄nanorods obtained after annealing at 500°C, were of high purity and polycrystalline in nature. The morphological analysis revealed that the basal & longitudinal dimensions of the obtained BiVO₄nanorods ranged from 350 to 450nm and 1.2-2µm, respectively. The effect of the annealed BiVO₄nanorods on the photocatalytic degradation of methylene blue (MB), a model pollutant, was evaluated with obtained results suggesting that the degradation of Methylene Blue in the presence of BiVO₄nanorods occurs at an efficiency of 82% under Solar Visible after 5h, at room temperature. These results show that bio-synthesized BiVO₄prepared using plant extracts of Callistemon viminalis could be a promising method for the synthesis of functional nanomaterials that find use as photocatalysts.