| Nano-material and nano-technology are one of the activest branchs, which include many rich research fields. Nano-material Science is a new knowledge that covers Atomic Physics, Condensed State Physics, Colloidal Chemistry, Solid Chemistry, Coordination Chemistry, Dynamics of Chemical Reaction, Surface and Interface Science and so on. The research of nano-material meet with many unknown process and novel phenomenon which are difficult to be explained by the traditional Physical and Chemical theories. The research process of nano-material must make a further step in the field of Physics and Chemistry and also bring the new opportunity.Because of the unique chemical and physical properties such as Surface Effect, Interface Effect, Quantum Size Effect, nano-materials are used in many fields, especially in the catalytic field. In the many forms of the nano-catalyst, the complex nano-material draws many attentions of the scientists. It is because complex nano-materials have the properties of both the nano-particals and the carriers. It is more especial than other materials.Now, the traditional preparation methods of complex nano-catalysts are chemistry method and physics method, such as immergence, ion-exchanged, adsorption, evaporation and sol-gel method. Compared with other methods, the sol-gel method has great advantage. The catalysts prepared by this method are made up with high-uniformity-dispersed nano-particals on the carrier. By the sol-gel method, the synthesized parameters are certain and the properties of products are certain and diversed. But there is fatal defect in the sol-gel method which is implanting of nano-particals. It can lead the low activity.In this paper, we developed one novel sol-gel method. The novel character is shorting of gelling time. It make the nano-particals dispersed in the gel network uniformly, which prevents the sediment and conglomeration of nano-particalsThere are two parts in this paper. One part is the preparation and characterization of solid superacid nano-catalyst SZ/SiO2.Since Arata and his coworkers reported the solid superacid of MxOy –SO42- free of chlorine in 1979, the MxOy –SO42- system has attracted the attention of many researchers.Through much research on this, many kinds of solid superacid were prepared such as ZrO2, TiO2, Fe2O3 or SnO2 immersing in the SO42-, WO42- or MoO42-.Among these systems, the sulfated zirconia, here called SZ, exhibits an acidity 10000 times stronger than that of 100% sulfuric acid. The SZ system can be used as catalyst for many reactions such as isomerization, alkylation dehydration and so on, so many researchers focus on it. Because the SZ system has the smaller BET surface area (the BET surface area is 100 m2/g after calcination after 600-650oC) and high acid strength, its catalytic life is very short even in the low temperature reaction . In this paper we prepared the SZ/SiO2 and SZ/SiO2-TiO2 by a sol-gel techniques. In there, zirconium butoxide was hydrolyzed to colloidal particles in the presence of a large amount of sulfated for the construction of solid super acid. After the SiO2(or TiO2,SiO2) and ZrO2 were homogeneously admixed at various ratios, a certain amount of cross-linking agent was added into the system to prevent ZrO2 colloids from self-agglomerating. The properties of the catalysts were characterized by TPD-NH3, SPS, H0, TEM, IR of pyridine adsorbed, XRD, BET, FT-IR and XPS. The results indicates that the SZ/SiO2 catalyst of 40% exhibits the strongest acid strength,of which superacid site is 50-60% of the total acid site. The superacid catalyst with a 8-nm diameter possesses a bigger BET surface area and a microporous amorphous structure. XPS results indicate that the SZ/SiO2 superacid namo-catalyst has a core-shell structure, therein the SZ particles are dispersed on the surface of SiO2 carrier. The research on several catalytic reaction indicated that this structure greatly increase the catalytic activity of SZ/SiO2. Through the research of acid, we found that the role of acid in th...
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