| TiO2/SiO2 is an important inorganic composite materials, playing a key role in chemistry, materials science, biology and engineering of interdisciplinary research. Compared with the single material, TiO2/SiO2 composite materials have better physical and chemical properties such as versatility, stability and dispersibility. More importantly, it can provide more active sites and synergistic effect between two kinds of materials, which makes the TiO2/SiO2 composites were widely used in various fields, such as catalysis, adsorption, separation, energy storage and conversion, drug delivery and optics, etc. TiO2 and SiO2 in specific hybridization can form more adsorption sites of organic molecules. With SiO2 as the basement of TiO2/SiO2 composites have better thermal stability, can effective adsorption of organic dye molecules, thus improving the photocatalytic properties; TiO2/SiO2 composite materials with larger specific surface area, good biocompatibility, and a lot of surface active groups, and organic material has good adsorption performance and become a good carrier of immobilized enzymes. The synthesis methods of TiO2/SiO2 composite materials were mainly of sol-gel method, hydrothermal method and microemulsion method, etc. on the basis of improving the Stober method, to form a composite with the controlling the size and morphology has been widely studied.This study was used modified Stober method on the basis of the synthesis of SiO2 microspheres by controlling different synthesis conditions to get different size of TiO2/SiO2 composite materials, and on this basis, to join the hexadecyl trimethyl ammonium bromide (CTAB) assisted synthesis of core-shell composite materials used for the immobilization of glucose oxidase, and optimum condition of immobili-zation and interface characteristics of immobilized enzyme was studied; Adding phenolic resin assisted synthesis of core-shell composite materials for light catalytic degradation of Rhodamine B, and the materials in different synthesis conditions on the degradation efficiency of the corresponding comparison has been studied.Results showed that the ratio of silicon to titanium and ammonia content had an effect on the morphology of the composites. Through regulating the proportion, and synthesized a more structured micro-spheres. At titanium silicon ratio of 1:1 and with ammonia content of 0.3mL, the morphology of the microspheres were neat. With the aid of CTAB or phenolic resin, composites under the same conditions was not with big difference compared with the original SiO2/TiO2 composites on size.The optimal conditions of CTAB assisted SiO2/TiO2 composites after the adsorption of glucose oxidase, was analyzed by orthogonal analysis. The best immobilized conditions were as the fellowes:the amount of enzyme of 0.09g/mL, temperature of 30℃, pH of 6.75 and immobilized time of 16h. SEM results showed that the changing in size of the core-shell materials was not obvious; The XRD peak strength was weakened and (112) crystal plane diffraction peak was disappear; The specific surface area and average pore diameter were decreased; FT-IR analysis showed that the amide Ⅱ area characteristic peak was shift and the peptide bond N-H plane bending vibration and C-N stretching vibration were changed, leading to a change in conformation, glucose oxidase adsorbed to the surface of SiO2/TiO2 successfully. Photocatalytic evaluation showed that the SiO2/TiO2 mesoporous microspheres for the degradation of rhodamine B rate was reached 98%.In the phenolic resin assisted synthesis process of composite materials, through regulating titanium silicon ratio and ammonia content, the microspheres were prepared. At the titanium silicon ratio of 1:1, adding amount of 0.30mL ammonia and under 550 ℃ calcination conditions, the photocatalytic properties of composite microspheres were preferably; At titanium silicon ratio of 1:1, ammonia content of 0.30 mL and under the condition of 650℃ calcinations, the highest photo-catalytic efficiency around 40min, Rhodamine B has been largely degradated. |
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