Characterization of the visible-light-driven BiVO4 photocatalyst synthesized via a polymer-assisted hydrothermal method

BiVO4 photocatalyst was synthesized by a polymer-assisted hydrothermal method at different temperatures and reaction times. Sodium carboxymethylcellulose was used in order to assist the formation of BiVO4 oxide. The resulting samples were characterized by X-ray powder diffraction, scanning electron microscopy, diffuse reflectance spectroscopy, and adsorption-desorption N-2 isotherms (BET). The predominant BiVO4 phase of the system within the 160-200 A degrees C range was the monoclinic crystalline structure, which was obtained in pure form only under certain experimental conditions. Short reaction times promoted the formation of linear arrays of BiVO4 formed by particles with irregular form ranging in size between 100 and 200 nm. The photocatalytic activity of BiVO4 samples was evaluated in the degradation of rhodamine B (rhB) under visible-light irradiation. The samples exhibited a higher activity when they were synthesized at higher temperatures and longer times of hydrothermal reaction. The total organic carbon analysis of a sample irradiated for 100 h revealed that mineralization of rhB by the BiVO4 photocatalyst is feasible.