Synthesis and Characterization of Magnetic TiO2/SiO2/NiFe2O4 Composite Photocatalysts

Magnetic TiO2/SiO2/NiFe2O4 composite photocatalytic particles with high crystalline TiO2 shell were synthesized via a mild solution route. The prepared composite particles were characterized with X-ray diffraction(XRD), transmission electron microscopy(TEM), high resolution transmission electron microscopy(HRTEM), scanning electron microscopy(SEM), ultraviolet-visible(UV-Vis) spectroscopy and vibrating sample magnetometer(VSM). The results show that the obtained TiO2/SiO2/NiFe2O4 composite particles were composed of spherical nanoparticles, about 30 nm in diameter, with several NiFe2O4 fine particles about 20 nm in diameter as cores and silica as coatings and barrier layers between the magnetic cores and titania shells. The photocatalytic activity of the composite photocatalytic particles was also investigated for the degradation of Basic Violet 5BN(BV5) under UV irradiation. About 97% of original BV5 decomposed in 360 min in the presence of magnetic composite nanoparticles under UV light. The synthesized magnetic composite nanoparticles exhibited high photocatalytic efficiency that would find potential application to cleaning polluted water with the help of magnetic separation.