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CeO 2 is an inexpensive and highly versatile industrial material, and has a broad market prospect. In recent years, the cerium oxide nanomaterials morphology, size, control, and performance applications has become one of the hot. This paper aims Hydrothermal Synthesis of cerium oxide and nanocomposites, and the characterization of their structure, morphology and optical properties. The main content of the study and the results achieved, specific summarized as follows: 1, using the hydrothermal method, in different solvents, surface active agents, are synthesized in the reaction under the reaction conditions such as temperature and time bundle, cubic, octahedral shape, The short rod, disc-shaped morphology of CeO 2 precursor structure, heat treatment at 500 ° C under micro and nano cerium oxide structure. (1), Ce (NO 3 ) 3 6H 2 O cerium source, urea as the precipitating agent, CTAB surfactant in different solvent concentration, reaction temperature and time, prepared by the micro and nano materials of different morphologies of the cerium oxide, summarizes the experimental process with the reaction time of the size of the cerium oxide material, variation of temperature, the successful implementation of nanoparticles size control, and causes a certain amount of discussion. The optical performance of the test conducted on the cubes prepared with the octahedral morphology of the cerium oxide nanoparticles. (2) to the CeCl 3 7H 2 O as a cerium source, urea as precipitation agent, PVP as a surface active agent, glacial acetic acid as a modifier, at 180 ° C under the reaction 3h obtained discoidal cerium oxide nanoparticles. The possible formation mechanism, and optical properties of the test. By hydrothermal method, 6H Ce (NO 3 ) 3 2 O, CeCl 3 7H < sub> 2 O as a cerium source, urea as the precipitating agent, glacial acetic acid as a modifier to join different metal oxide precursor, in a certain proportion of mixing to prepare a different morphology the CeO of 2 -MOx (M = Cu, Si, Ti, Al, of Zn, of Fe, Co) nanocomposites precursor. After the heat treatment, to obtain a composite material in its oxide. (1) Synthesis of a nanowire structure of CeO 2 -CuO morphologies uniform. The nanowires diameter of about 10-20nm, up to a few microns. After the HRTEM and SAED test of characterization that CuO nanoparticles attached CeO 2 nanowires. Explore the possible formation mechanism of the nanowires that glacial acetic acid plays a key role in the formation process of nanowires. The tests show that the nanowire structures of UV-vis in the ultraviolet region and the visible region, has good UV absorption properties. (2) was synthesized using the same method CeO 2 -MOx (M = Si, Ti, Al, Zn, Fe, Co) composite material, the same XRD, FESEM, UV-vis, and so on morphology and performance characterization. (3) Preparation of the-Fe of CeO 2 2 O 3 nanomaterials α-Fe 2 O 3 hollow nanorod array structure, FESEM, TEM analysis showed that the The nanorods top tetragonal structure, the end of the needle-like structure. The average length of 60-70nm, and the diameter of 20-30nm. HRTEM analysis showed that the [021] growth direction of the nanorods. UV test showed that CeO 2 O 3 UV shading effect of nanomaterials significantly better than CeO 2 -MOx 2 -Fe (M = Si, Ti, Al, Zn, Co) composite material. 3, using a two-step hydrothermal synthesis method, under certain reaction temperature and time, were synthesized the CeO 2 @ C and of CeO 2 -SiO 2 @ C nanostructures. The thickness of the layer C can be controlled by the adjustment of the amount of reactants and reaction time.
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