Photocatalytic activity of BiVO4 nanospheres obtained by solution combustion synthesis using sodium carboxymethylcellulose

BiVO4 nanospheres were obtained through solution combustion synthesis (SCS) in presence of sodium carboxymethylcellulose (CMC). The CMC polymer had a double function, as a fuel and as a protecting agent in the particles growth process. The formation and characterization of oxide was carried out by simultaneous thermal analysis (TGA/DTA), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), and surface analysis (BET). The as-prepared BiVO4 nanospheres calcined at 300 °C exhibited higher photocatalytic activity under visible-light irradiation than BiVO4 samples prepared by coprecipitation and solid-state reaction methods in the degradation of rhodamine B (rhB). This behavior could be associated to their higher specific surface area (BET) and morphology. The analysis of the total organic carbon showed that the mineralization of rhB over a BiVO4 photocatalyst is feasible (43% after 100 h of irradiation). A mechanism of formation of BiVO4 nanospheres is also discussed.

The spherical morphology was induced by the addition of CMC polymer that acts as stearic stabilizer. The resulting particles were encapsulated by the adsorption of CMC on the surface, which inhibited the disorder growth of the particles.Figure optionsDownload high-quality image (183 K)Download as PowerPoint slideResearch highlights▶ This work is in the direction of searching alternative materials to take advantage of the solar energy. ▶ We propose the use of sodium carboxymethylcellulose as additive during the BiVO4 synthesis. ▶ The prepared BiVO4 nanospheres exhibited high photocatalytic activity under visible irradiation. ▶ The analysis of TOC showed that the mineralization of rhB over a BiVO4 photocatalyst is feasible.