Preparation And Application Of Magnetic Photocatalytic Hybrid Materials

Recently, research of composite materials had been a hot research topic as one of the frontier science. Composite materials not only modify properties of homogenous materials, but also produce some novel properties, such as improving particle stability, adjusting properties of photics and magnetics and et al. These materials have wide applications because they can satisfy some kinds of special requirements.In this paper, several kinds of composite materials were prepared which had well magnetic response and photocatalysis. They displayed well degradation effects in wastewater treatment under UV/US combination method.1. Preparation of magnetic photocatalystMagnetic Fe3O4 with well water-solubility were prepared using hydrothermal method. TiO2/SiO2/Fe3O4 and TiO2/Fe3O4 were prepared using sol-gel method while P25/Fe3O4 were prepared with the help of electrostatic interaction. The as-synthesised composite materials showed both well magnetic response and photocatalysis. And these composite materials were characterized by TEM, FESEM, and XRD respectively.2. Degradation of wastewater under UV/US combination methodThe photocatalytic activity of the as-synthesised magnetic photocatalysts were investigated by photocatalytic degradation of methylene blue(MB), 2-chlorophenol(2-CP) and actual wastewater. We tried to find out the best degradation condition considering the amounts of catalysts, the power of ultrasonic, the time of degradation reaction, the influence of aeration and the difference between UV/US combination and UV and et al. The degradation results were detected by UV-vis, HPLC, and COD respectively. For MB simulated wasterwater, the photocatalytic efficiency was over 90% under optimal condition while UV/US combination method heightened about 20%. For 2-CP simulated wasterwater and actual wasterwater, the as-synthesised magnetic photocatalysts were better than commercial catalyst P25 under optima condition. And for actual wasterwater, the photocatalytic efficiency can reach 80% under UV/US combination method.3. Preparation of luminescent magnetic particlesMagnetic Fe3O4 was coverd by an outer layer of SiO2, and then luminescent Au NCs were put on the surface of SiO2/ Fe3O4. The as-synthesised composite materials showed both well magnetic response and fluorescence. And these composite materials were characterized by RF respectively.