Rapid preparation of Bi2WO6 photocatalyst with nanosheet morphology via microwave-assisted solvothermal synthesis

Nanocrystalline Bi2WO6 photocatalyst with nanosheet morphology was successfully synthesized by a microwave-solvothermal process. The prepared samples were characterized by X-ray diffraction technique (XRD), BET surface area analysis, Uv–vis diffuse reflectance spectrum (Uv–vis DRS), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). In comparison with a conventional hydrothermal process, the microwave-solvothermal process presented many advantages in a shorter reaction time, higher surface area and more oxygen vacancies for the preparation of Bi2WO6 samples. The absorption edge of the samples is at ca. 445 nm, corresponding to band gap energy of about 2.8 eV. The morphology of nanosheets with nanocrystals was also observed. For the decomposition of Rhodamine B (RhB) under visible light irradiation (λ > 420 nm), nanocrystalline Bi2WO6 samples obtained by microwave-solvothermal process showed higher photocatalytic activity than that of the sample obtained by conventional hydrothermal process.