| Stone, bronze, iron: civilization has always been defined as Man's relationship with materials that they have used in their daily life. The progress of technology is directly or indirectly depended on the progress of materials.Nanomaterials is a new class of materials that has been making a silent revolution in the past few years. It is the foundation of the nano-technology and is causing an extensive concern of all over the world. The properties of nanomaterials show remarkable improvement or deviation from the properties exhibited by the common materials. They exhibit a unique optical, magnetic, electric, or catalytic activity property. These properties are attributed to the significant increase in grain boundary area due to the small grain size. Area of application that can be foreseen to benefit from the small size include quantum electronics, nonlinear optics, photonics, chemicalselective sensing, and information storage and processing, adsorbents, catalysis, solar cell, magnetic recording devices, superplastic ceramics, superhard metals, metastable alloys and so on.In general, researches in nano-materials are mainly concerned with the development of of new synthesis of methods, new ways of characterizing materials and applications of them. Of course, the first step is the synthesis of the materials. In this thesis, LCS was employed to prepare Nd2O3, CeO2, Fe2O3-CeO2 nanoparticles and corresponding solid acid. Their structure, size and morphology were characterized by XRD, TEM, AFM, IR.The main content is shown as following:Part One ReviewChapter OneIn this chapter, we mainly describe the development of the nanomaterials, some basic and specific properties of nanomaterials and the application of nanomaterials.Chapter TwoIn this chapter, we stated the development, mechanism of Combustion Synthesis (CS), a new method to synthesize materials. CS consists of Self-propagating High-temperature Synthesis and Low-temperature combustion Synthesis. Thedifference an the similarity between SHS and LCS were described in this chapter.Part Two ExperimentsChapter One Synthesis of Nd2O3 nano-powder by sol-gelauto-combustion and its catalytic esterification activityNd2O3 nano-powders were prepared by a novel sol-gel auto-combustion method using additive agent polyvinyl alcohol. The gel transformed from the aqueous solution of metal nitrate, citric acid and small quality of polyvinyl alcohol underwent an auto-combustion process when ignited and yielded voluminous ashes. These ashes were single phase Nd2O3 powder with a particle size distribution of 20-30 nm. The influences of preparation conditions such as the molar ratio of Nd3+ to citric acid, the amount of additive agent, the pH value of the reaction system on the formation of the particles have been studied in detail. X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used for the sample characterization. It was found that the optimum molar ratio of Nd3+ to citric acid was 1:2, the optimum amount of polyvinyl alcohol was 10 percent of Nd(NO3)3. In addition, we also studied the catalytic activity of nanometer Nd2O3 and solid acid SO42-/Nd2O3 in synthesis of isobutyl acetate.Chapter Two Shape-control of CeO2 nanoparticles and synthesis of nano-metric solid acid SO427CeO2Nanoparticles of CeO2 with the smallest average particle-size (18.7 nm) and spherical morphology were obtained from a mixture solution of Ce(NO3)3.6H2O, citric acid, polyvinyl alcohol by a auto-combustion process exploiting sol-gel as precursors. The course of size-control and shape-control by polyvinyl alcohol was examined in detail. A transmission electron microscopy (TEM) and an atomic force microscopy (AFM) were employed to characterize the particle-size and morphology of CeO2 particles. Additional, a sort of nano-metric solid acid SO42-/CeO2 based on CeO2 nanoparticles was prepared by macerating, filtering, drying and calcining processes. The particle-size of SO42-/7CeC>2...
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