| Nanoscale physics and technology, developed from the early 1980s, will be the leading technology in the near future. Since nanoscale materials take much more advantages than traditional materials, they will be applied to many kinds of industrial fields. As an ordinary ceramic material, Zr O2 has many special characters in luminescence. Moreover, when a surface of zirconia ceramic is exposed to a laser under controlled conditions, this area is transformed from a hydrophilic to an oleophilic state, the same condition occurs in the counter procedure. This special character is intriguing more and more researchers in recent years. Nanometric ZrO2 powders are a technologically important class of materials with a wide range of applications and the powders with narrow size distribution are intensively sought as raw materials for advanced ceramics. These applications including optical devices and electrochemical capacitor electrodes, oxygen sensor, fuel cells, photocatalysts and advanced ceramics, etc.Summarize: there are several conclusions in this thesis:(1) Under room temperature, we got stabled tetragonal nanometric ZrO2 powder synthesized by microwave-irradiation and ultrasonic respectively.We utilized XRD, TEM to characterize these nano- ZrOi samples, we found it is clear that these samples are crystal and distributed well, and the average particle diameter is 1.0-2.0nm (before annealed).(2) We utilized PL spectra (Photoluminescence spectra) to characterize the samples synthesized by microwave-irradiation. When the samples were excited by 254nm ray, we got a widen emission luminescence band, there are two clear crests corresponded to 458nm and 482nm; When the samples were excited by 412nm ray, the emission luminescence band is between 550nm and 625nm, and the crest is 615nm.(3) We also utilized PL spectra (Photoluminescence spectra) to characterize the samples synthesized by ultrasonic. When the samples were excited by 254nm ray, the emission luminescence band is corresponding to three crests: 402nm, 420nm, 459nm; When the samples were excited by 412nm ray, the two clear crests are 530nm and 608nm, and the relative intensity of 608nm crest is much higher than the 530nm crest. The cause of the photoluminescent difference between naon-ZrO2 synthesized by microwave and ultrasonic wasalso discussed in the thesis.(4) In order to validate the special character of ZrO2 that the transformation between a hydrophilic state and an oleophilic state when the surface of zirconia ceramic is exposed to a laser under controlled conditions, we have done some experiments.This thesis is composed of seven sections, including the introduction, which give a brief introduction to the significance of studying nanoscale materials' luminescent characters and the theory of solid materials luminescence.Chapter one is the theoretical part of solid materials luminescence, in this section, we discuss the theoretical model of solid materials luminescence, especially semiconductors.Chapter two offers a particular discussion on the special characters of nano-sized materials, especially on the difference between traditional materials and nanoscale materials. We also discuss luminescent effects caused by the nanometer.Chapters three and four are the kernel of this thesis. Chapter three is a detailed presentation about experiments we have taken, in order to get good samples, we took two simple methods for the preparation of stabilized ZrO2 nano-powders. We utilize XRD (X-ray diffraction), TEM(Transmission Electron Microscope) and PL spectra(Photoluminescence spectra) to characterize these samples. In Chapter four, we analyze the photoluminescence(PL) excitation and emission spectra of the nano-ZrC>2 powders and focus on offering a reasonable interpretation about the luminescent characters of ZrOa nanocrystal. Moreover, we explore on setting up the theoretical model of other oxide nanocrystals' luminescent procedures.Chapter five is the complementary experiment of the research on luminescent mechanism...
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