Synthesis and characterization of SiO2/Bi2WO6 based on biogenic silica synthesized by sol-gel method

Abstract

SiO2/Bi2WO6 photocatalyst with Si/Bi/W=1:2:1 molar ratio was obtained by the sol-gel method from bismuth nitrate, sodium tungstate and biogenic silica from rice husk biomass followed by calcination. Bi2WO6 was used as a control sample. FT-IR, SEM, XRD, EDXRF, UV-Vis methods were used to systematically characterize the as-obtained materials. Photodegradation of Indigo Carmine in exposure to UV, sunlight and xenon light was studied to evaluate their photocatalytic activities in the presence of SiO2/Bi2WO6 and Bi2WO6. It was shown that the degradation degree of Indigo Carmine in the presence of SiO2/Bi2WO6 under the action of UV irradiation and sunlight reaches 36% and 14%, respectively. The SiO2/Bi2WO6 sample is stable during photocatalytic studies.