Synthesis and characterization of monoclinic BiVO4 nanorods and nanoplates via microemulsion-mediated hydrothermal method

Monoclinic BiVO4 nanorods and nanoplates were synthesized via the CTAB/water/n-butanol/n-octane microemulsion-mediated hydrothermal process. The physical and photophysical properties of the as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, and UV–vis diffuse reflectance spectroscopy (UV–vis). It was found that the ratio of H2O to CTAB in microemulsion played a key role in the morphology evolution of the products. The possible formation mechanism of BiVO4 nanostructure with various morphologies was briefly discussed. The Raman results indicated that the symmetry distortions in the local structure of the synthesized BiVO4 were affected by the morphology of the products. The bandgaps (Eg) of BiVO4 nanorods and nanoplates are 2.45 and 2.38 eV, respectively. The synthesized BiVO4 nanoplates showed superior photocatalytic activity compared with BiVO4 nanorods due to their higher degree of structural distortion, larger surface area, and thinness.

► Microemulsion-mediated hydrothermal approach to BiVO4 nanorods and nanoplates.
► Formation of BiVO4 nanostructure was based on an oriented aggregation process.
► Ratio of H2O to CTAB played a key role in the morphology evolution of BiVO4.
► BiVO4 nanorods and nanoplates showed high activities for photodegradation of MB.
► Higher structural distortion enhances the photocatalytic activity of BiVO4.