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Hydrotalcite (Layered Double Hydroxides, LDHs) is a layered inorganic multifunctional materials, inorganic-organic composite applications are often complex formation with organic molecules. Hydrotalcite itself can be harmful adsorption of organic molecules, play the role of the water treatment. Meanwhile, the dye molecules are intercalated hydrotalcite can also be used as the use of the multifunctional material. The roasted product hydrotalcite precursor spinel semiconductor composite later because of its wide range of light absorption is often used in photocatalytic technology, especially in the degradation of organic pollutants, outstanding. This thesis the the hydrotalcite precursor calcined product selectivity light degradation of the performance of its mechanism of dye molecules, the fluorescent properties of the dye molecules intercalated hydrotalcite composite materials. The specific contents are as follows: 1. Prepared by spray drying to obtain microspheres of uniform particle size distribution of the hydrotalcite, after roasting, after to obtain ZnO/ZnAl2O4 composite materials, its morphology and particle size distribution, specific surface area, pore size distribution study and for methylene blue (MB), methyl orange (MO) by UV degradation. The results show that: the microspheres are prepared by spray drying to obtain a hydrotalcite hydrotalcite sheets stacked, the narrow pore size distribution, large surface area, readily adsorbed dye molecules, and after firing can be maintained spherical morphology. Experimental results show ZnO/ZnAl2O4 microsphere composite photodegradation of MB. MO photocatalytic degradation, degradation efficiency of approximately 98%, reusable. MB and MO of the same concentration of a volume ratio of 1:1 mixed, ZnO/ZnAl2O4 microsphere composite material having a selective degradation effect preferentially degraded an MO, and the optical degradation rate of about 98%. And further experimental and theoretical interpretation of the composite material of ZnO/ZnAl2O4 microspheres MB, MO photocatalytic degradation and selective degradation mechanism. By infrared characterization means that its surface having adsorption properties, by calculating the forbidden band width of the composite material of the ZnO/ZnAl2O4 microspheres explained, from the angle of the charge and the hole of the moving process of the photocatalytic mechanism MB, MO. MB, MO selective photodegradation mechanism by CO2-TPD method confirmed ZnO/ZnAl2O4 composite microspheres surface alkaline, easy-adsorption of acid molecules. Therefore, MO molecules can be preferentially adsorbed to the surface of the catalyst is degraded. Also indicates MO reaction, the catalyst surface acidity plays a major role in ZnO/ZnAl2O4 microsphere composite selective photocatalytic degradation of MB. 2 using an electrostatic spinning method, prepared the Sulforhodamine Intercalation CaAl-LDH/PVA composite fiber membrane. The body of water talc dispersed in the PVA-fiber membrane, and to examine the performance of the fluorescence of the composite film in the different pH conditions and antifade. The results show that: water talc body easy to aggregate, and with the increase of added amount of the hydrotalcite, agglomeration phenomenon is particularly evident. When the ratio of PVA and hydrotalcite appropriate, hydrotalcite can be uniformly dispersed in the PVA film and has a good fluorescence properties. Presents a linear change in the fluorescence intensity of the composite film in the range of the pH value of 7.0-9.4, is expected to be used for this pH range detection pointer; and the film at 400mg/ml of NaCl solution remains fluorescence activity, has excellent The antifade Performance.
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