Design, Synthesis And Application Of Functional Micro-Nano Materials

Because of their different physical and chemical properties, specific functional applications of nano-materials is very extensive. The morphology and size of nano-particles have a important influence on properties of the materials. So it is important to control the particle size and morphology in the process of preparation of nano-materials. Different synthesis methods have their own advantages and disadvantages. We explored different ways to synthesize nano-material including the flakyα-Al2O3 polishing material, yttria-stabilized zirconia (YSZ) toughened ceramic materials, and blue light-emitting CdS/ZnS core/shell nanocrystals. The samples were characterized by electron microscopy (EM), powder X-ray diffraction (XRD). UV-vis absorption and Photoluminescence were also used to characterize the growth process and optical properties of nanocrystals. The main experimental contents are as follows:In this paper, my research working mainly focuse on three aspects:i)α-Al2O3 preparation and its polishing performance; ii) yttrium-stabilized zirconia (YSZ) toughened ceramics; iii) preparation of fluorescent CdS/ZnS core-shell semiconductor nano-materials.(1)α-Al2O3 polishing materials were prepared via the glycine-nitrate pyrolysis process and the polishing performance of the obtained product was studied in detail, which shows comparative performance in comparison with the commercial products.(2) Stable monodisperse tetragonal YSZ nano-particles were prepared through the modification of industrialization precipitation incombination with the use of ultrasound and microwave techniques. The phase toughening mechanism of the obtained product was exploited.(3) Wurtzite structured CdS nanoparticles were firstly synthesized as cores. Successive Ion Layer Adsorption and Reaction (SILAR) method was applied to grow ZnS shell around the CdS cores by alternative injection of the Zn and S precursors. The obtained core-shell structured CdS/ZnS nanocrystals with photoluminescent emitting wavelength in the range of 410-480nm show high emission efficiency (up to 45%) and good stability.