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Nanomaterials and technology is the most dynamic field of nanotechnology research is very rich in content disciplines branch. Nanomaterials science atomic physics, the aggregation state physics, colloid chemistry, solid state chemistry, coordination chemistry, chemical kinetics and surface and interface science and other interdisciplinary convergence and new disciplinary subject. Many unknown process involved in nanomaterials and novel phenomenon, it is difficult to explain with traditional physical, chemical theory. Sense nanomaterials research progress is bound to many disciplines of physics, chemistry field to a new level, and will bring new opportunities to the 21st century physics, chemistry research. Nanomaterials many unique physical and chemical properties, such as surface effects, interface effects, quantum size effect and macroscopic quantum tunneling effect it has great value in many areas. In the field of catalytic industrial nanomaterials has a broad prospect. Nanomaterials as catalysts in many forms, among which supported composite nanomaterials most impressive. Because, composite and has a small size effect of nanoparticles, surface effect, particles synergies and polymer materials soft, stable, easy to process basic characteristics, so it has special properties that other materials do not have. Currently, the traditional preparation of composite nanocatalysts divided into physical, chemical preparation, summed up: the immersion method, ion exchange, adsorption, evaporation, alkoxide and sol-gel method. Compared with other methods, the sol - gel method has a great advantage. The catalyst prepared using this method, the nano-particles can effectively a uniform dispersion is formed in the carrier network is more stable than a catalyst prepared by other methods. Using conventional sol - gel method, known in the synthesis parameters, the nature of the product obtained is also known, and diversity. However, using traditional sol - gel method of preparation of the composite catalyst also has a fatal flaw. Nanoparticles that is embedded, which leads to the low activity of the catalyst. In this article, we have developed a novel sol - gel method. Feature of this method is greatly shorten the gel time, so that the nano particles are relatively uniform is limited in the gel network, LT; WP = 81 GT; This prevents the deposition of nano-particles and in the calcination process a large number of aggregation. In this paper, we study is divided into two main parts. One is the use of this novel sol - gel method preparation and study of the binary complex of SZ/SiO2 solid superacid catalyst system. Solid superacid catalysts to overcome the serious equipment corrosion potential in industrial liquid acid catalyst, catalyst recovery difficult, easy to pollute the environment, and other ills, so nearly half a century, people put more attention on the solid superacid system. In the many solid superacid system, SO42-/ZrO2 system is by far the most typical is the highest acid strength the solid superacid system one of its highest acid strength of up to 100% of sulfuric acid 10,000 times. However, due to its higher acid strength and SO42-/ZrO2 into this harsh acid conditions (high temperature), it is the existence of surface area is small, easy to reunite, rapid inactivation shortcomings. In order to solve these problems, we use a novel sol-gel technique for the active ingredient to SO42-/ZrO2 prepared compound SZ/SiO2 catalyst system, in this process, we use a silane crosslinker SiO2 carrier rapidly gel and the ZrO2 particles are dispersed in the structure of its network, to achieve a dispersion of the nanoscale. The TPD, H0 and pyridine adsorption infrared spectroscopy results show that the SZ/SiO2 binary complex the catalyst superacidity, and L acid sites and B acid sites coexist superacid amount of 50-60% of the total amount of acid. XRD, BET, XPS results show that this SZ/SiO2 binary composite catalyst is a microporous, with a large specific surface area and the material of the core - shell structure, in which the relationship between SZ and SiO2 the relationship between the load and the load. The study shows that such a structure greatly improves the activity of the catalyst of several catalytic reactions. Change for other acid by the sulfuric acid in the system, we believe that the role of acid in the preparation process is to promote the ZrO2 peptization, and the study shows the role of a crosslinking agent is to prevent ZrO2 nanoparticles reunion crosslinker. The second is that we use this novel sol - gel synthesis and study nanocomposite Ag/SiO2 system. We all know that the nano-silver composite ceramic material as a carrier material has a wide range of applications, such as photovoltaics, membrane separation and catalyst. The supported silver catalyst as the industrial catalysis lt; WP = 82 GT; agent commonly used in the selective oxidation reaction, alkanes, alkenes and methanol aromatization reaction. In this section, we take advantage of the one-step and two-step synthesis of nano-supported silver catalyst. And the study of its structure and synthesis mechanism. Test results show that after firing Ag/SiO2 sample has a larger specific surface area, particle diameter of 20-30nm Ag or Ag oxide is used as a functional component, SiO2 as the carrier material similar to the core - shell structure . Different synthesis methods have a larger impact on the crystallization of the sample, sample one-step synthesis of a single crystal structure, the two-step synthesis of samples of mixed crystal.
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