| Porous materials, depending on the unique property, have shown tremendous potential with the development of the materials science. It is excellent catalyst, separator, microreactor and ion exchanger for their high specific surface and open structure, that plays an important role in extensive field, such as absorbsion, separation, and catalyst chemicals. Besides the remarkable property as catalyst, Ordered macroporous materials are also an essential photonic crystal with important and extensive practice value in communication and optical element field through affecting the propagation of electromagnetic wave by their photonic band-gap. It also can prepare biomimetic materials and self-cleaning materials according to structural color and lotus effect.The brief of this thesis is controllable synthesis of three-dimension ordered macroporous silicon oxide and multiscale ordered porous cerium zirconium oxide and analyzing the phase and size and by multiple methods of test and characterization by controlling the condition of the reaction. According to the result, we have researched the synthesis and potential application of ordered porous materials. The extension of the research and the result will be discussed as below.(1) Controllable synthesis of three-dimension ordered macroporous silicon oxide photonic crystal Photonic crystal has unique photonic band-gap, which prohibits propagation of electromegnitic wave with specific wavelength, that means, the motion of photon can be controlled by this mechanism. In this thesis, we use these property to control spontaneous radiation of NaYF4:Yb,Er upconversion nanopartials. At first, we regulated the condition of the reaction to get the long range ordered three dimension colloidal crystal template(3DOM), then filled the template with silicon oxide precursor, that was tetraethoxysilane(TEOS) doped NaYF4:Yb,Er upconversion nanopartials. When it was completely dry, we removed polystyrene spheres by burning, and got silicon oxide photonic crystal doped by NaYF4:Yb,Er upconversion nanopartials with inverse opal structure. We analyzed the size, structure and emission by SEM, TEM, UV/Visible and fluorescent spectrometer. According to the research, it was found that the significant variation of emission between NaYF4:Yb,Er upconversion nanopartials in and out photonic crystal. In this thesis, the emission modification of nanopartials has been achieved. We believed that is the control with the property of materials by ordered structure, which is an efficient example that can be extended to discover the property of ordered structure materials.(2) Multiscale ordereded porous cerium zirconium oxideCerium is an important kind of catalyst, which has high redox activity in high temperature. If zirconium is added into cerium oxide,that compose ceria-zirconia solid solution, the stability of the materials is increased remarkably, which is the reason why it has been used widely as oxygen storage body of three-way catalyst(TWC) to decrease the air pollutants such as CO, NOx, and hydrocarbon compounds emitted by automobile. In traditional materials, researchers synthesized ordered mesoporous materials based on ceria-ziaconia solid solution to increase the specific area of materials and active-site center of reactions. In this thesis, we attempted to add macroporous and mesoporous into ceria-zirconia solid solution at the same time, which composed multiscale macroporous cerium zirconium oxide. It is not only increased the specific area but also improved the efficient of mass transfer. And we attempted to modify the catalytic ability of material by ordering the porous.We hope to develop an easy and economic method to controllably synthesize ordered hierarchically porous materials, and then explore the application of hierarchically order in chemistry. |
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