Photocatalytic Degradation of Methylene Blue Dye Using TiO₂and Fe₃O₄/SiO₂/TiO₂as Photocatalysts

Abstract

Abstract This paper is focused on obtained two catalysts such as TiO 2 nanoparticles and Fe 3 O 4 /SiO 2 /TiO 2 nanocomposite for adsorption and photocatalytic degradation of methylene blue (MB) dyes from aqueous solution. The morphology, structure and chemical proprieties of synthesized materials were investigated by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), N 2 adsorption-desorption isotherms and Zeta potential. The photocatalytic degradation of methylene blue under UV light in the presence of different synthesized catalysts was analyzed with Spectrometer UV-Vis. The photocatalytic degradation of methylene blue was studies by focusing of photoactivity performance of Fe 3 O 4 /SiO 2 /TiO 2 in comparation with TiO 2 . An attempt has been made to study the effect of process parameters through amount of the catalysts and initial concentrations of methylene blue. In all cases was found that the kinetics of the MB photocatalytic degradation under UV light was fitted to the Langmuir–Hinshelwood. Even if the photocatalytic degradation study revealed that Fe 3 O 4 /SiO 2 /TiO 2 and TiO 2 degraded about 90 % of methylene blue within 60 min, the magnetic nanocomposite Fe 3 O 4 /SiO 2 /TiO 2 serves as better catalyst compared with TiO 2 nanoparticles. An important role in the photocatalytic degradation of MB is adsorption characteristic of TiO 2 and Fe 3 O 4 /SiO 2 /TiO 2 surface. The photocatalytic performance of Fe 3 O 4 /SiO 2 /TiO 2 remained greater than TiO 2 after 4 cycles of use.