Effects of citric acid and urea on the structural and morphological characteristics of BiVO4 synthesized by the sol-gel combustion method

摘要

Micro-sized spherical BiVO4 photocatalysts composed of nanoparticles were synthesized by the sol-gel combustion method. The effects of citric acid and urea on the structural and morphological characteristics of samples were studied by X-ray diffraction, field emission scanning electron microscopy, N-2 adsorption and desorption and UV-Vis spectroscopy. The photocatalytic activity was evaluated by the photocatalytic degradation of rhodamine B under visible light. The results showed the sphere-shaped BiVO4 sample to have excellent photocatalytic performance compared with the bulk sample prepared by solid-state reaction. This enhancement could be attributed to the special spherical morphology, which enhanced the absorption ability, increased the separation efficiency of photon-generated carriers and improved surface reaction sites for consumption of photon-generated carriers.