Preparation And Photocatalytic Properties Of CoFe <2> 4 / MCM-41 / TiO 2 Composites

TiO2 photocatalytic technology is a kind of environmentally friendly and efficient pollution control technology, how to improve the TiO2 photocatalytic activity and solve the problem of recycling has become a hot topic in the new study. Based on the study the researchers CoFe2O4 / SiO2 / TiO2 composite photocatalyst,in this paper, on the basis of retaining the semiconductor compound between SiO2 and TiO2, reduce the shielding effect of the intermediate layer and increase its effective role area by introducing the intermediate layer of mesoporous structure, The prepared magnetic CoFe2O4 / MCM-41 / TiO2 composites material to further improve the efficiency of its photocatalytic. The crystal structure, morphology, pore structure and magnetic properties of the prepared samples were characterized by XRD、SEM、TEM、N2 adsorption-desorption、FI-IR、Uv-vis、 XPS、VSM. Meanwhile, the prepared magnetic CoFe2O4 / MCM-41 / TiO2 composite materials used for photocatalytic degradation of simulation phenol wastewater.First of all, the preformed monodisperse magnetic CoFe2O4 particles were prepared by solvothermal method. By the results of characterizing showed that the prepared magnetic CoFe2O4 particle with complete crystal forms, uniform size and good dispersivity, the size was about 100 nm, the saturation magnetization intensity was 77.0emu/g. Sceond, the intermediate MCM-41 layer was prepared by the method of liquid crystal templating mechanism. By the results of characterizing showed that the intermediate MCM-41 was in the amorphous form of prepared the magnetic of CoFe2O4/MCM-41 composite material, uniform size and good dispersivity of the spherical particles, the size was about 580 nm, the saturation magnetization intensity was 9.5emu/g, besides it presented high surface and excellent pored structure characteristics, the surface area was 1015.3 m2/g, the pore volume was 0.69 cm3/g the pore size was 2.69 nm.Finally, TiO2 shell of CoFe2O4/MCM-41 composite material was synthesized by the method of esters precipitation. By the results of characterizing showed that the prepared the magnetic of CoFe2O4/MCM-41/TiO2 composite material could increase the phase transition temperatures of TiO2, and the composite materials had strong absorption in the ultraviolet and visible light conditions, and expanding the photoresponse range to visible light area. it showed uniform size and good dispersivity of the spherical particles, the size was about 660 nm, the saturation magnetization intensity was 7.4 emu/g, besides it presented high surface and excellent pored structure characteristics, the surface area was 1015.3 m2/g, the pore volume was 0.46 cm3/g the pore size was 2.93 nm. Combined with its characterization analysis, we concluded that the prepared magnetic CoFe2O4/MCM-41/TiO2 composites material had excellent photocatalytic properties, and it could be easily recovered by a magnet.The photoreaction vessel was exposed to Xenon lamp irradiation under the 500 W irradiation. The photocatalytic activities of the magnetic samples were evaluated by the degradation of phenol in an aqueous solution. Chose the best plan of degradation through the comparison of the different preparation process conditions and reaction process condition. Through a series of degradation experiment, we found the degradation rate of phenol achieved up to 85%, after used 6 cycles, it also maintained high degradation rate and removal rate。...