Surface Modification of a Magnetic SiO2 Support and Immobilization of a Nano-TiO2 Photocatalyst on It

This study presented an effective method to modify the surface chemical reactivity of a SiO2/Fe3O4 support. The unmodified SiO2/Fe3O4 support was prepared by the hydrolysis and condensation of tetraethoxysilane on the surface of hydrophilic Fe3O4 nanoparticles. These were then modified by a heat treatment in an ethanol/water solution under reflux, The resulting samples were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and transmission/scanning electron microscopy. The immobilization of a TiO2 nanocatalyst on both unmodified and modified supports was performed to investigate the effects of the modification of the magnetic silica support on the loading of a TiO2 nanocatalyst and the photocatalytic activity. The loading of TiO2 and the photocatalytic activity were both improved.