| With the rapid development of luminescence materials in these recent years, as well as the growing requirement of these materials in real-life situations, both fluorescent membrane and phosphors have been research focuses, and aroused extensive concern in recent years.In the current master dissertation, three major topics have been involved. Firstly, the Y0.5-xGd0.35Eu0.15BixNb04(0<x<0.30) and Y0.35Gd0.35Eu.015Bi0.15Nb1-yPyO4 (0≤y≤0.20) phosphors have been synthesized by the conventional solid-state reaction. As for these Y0.5-xGd0.35Eu0.15BixNb04 (0≤x≤0.30) samples, with increasing Bi content, the emission firstly increases and then decreases. Therefore, the maximum emission is achieved when x is 0.18. This tendency is closely related to the following two factors. One is the energy transfer process between Bi3+ ions and Eu3+ ions, the other is related to the distortion of the crystal field surrounding Eu3+ ions. About those Y0.35Gd0.3sEu0.15Bi0.15Nb1-yPyO4 (0≤y≤0.20) samples, the emission and excitation intensities are both varied with the P doping content. The strongest intensity is obtained in the case of y= 0.15. This is also ascribed to the following two factors. One is the increasing absorption of VO43- with the increase of the P5+ content, and the other is the nephelauxetic effect which may also influence on the Eu3+ emission intensity. Our obtained results suggest that the Bi dopant acts as one sensitizer and eventually enhances the photoluminescence intensity. The introduction of PO43- also plays an important role in the photoluminescence properties of the investigated samples. Secondly, Y2O3:Eu3+(5%), Li+(x%) phosphor thin film has been prepared by electro-deposited method. The XRD data show that the doped Li+ions do not change the structure of Y2O3:Eu3+. SEM results suggest that the samples are composed of a large number of uniform nano-structure flakes. With Li doping, the flakes aggregate gradually and the flower-like micro-architectures are observed. The emission intensity is enhanced with Li doping level increasing from 0 to 15%, and then declined with Li doping further. The enhanced luminescent efficiency is ascribed to the following factors. One is the decrease of OH- group as shown in FI-TR result, and the other is related to the oxygen vacancy generated by Li ion incorporation in the lattices. At the same time, the deposition time and the solution concentration are also the important factors determining the morphology and the emission intensity of Y2O3:Eu3+(5%), Li+(x%) thin film. Thirdly, Ba2+-doped Y0.75Bi0.15Sm0.10VO4 are also synthesized using a conventional solid-state reaction route. X-ray diffraction and fluorescence spectrophotometer were used to investigate the effects of doping Ba2+ ions on the crystal structure and luninescence properties of the samples.This dissertation is organized in the following way. In section one, Y2O3:Eu3+ thin film has briefly introduced, including the application of Y2O3:Eu3+ thin film, the crystal structure, and the luminescence properties. At the same time, research progress of rare earth doped oxide system has also been reviewed. The research significance and purpose of this dissertation are also presented. In section two, experimental conditions are then introduced. These specific conditions include the experimental instruments and reagents, pharmaceuticals and those for the characterization methods and techniques of the samples. In the following three sections, three major topics mentioned above are presented in detail. In section six, the dissertation is summarized, and the forecast of our work and prospect of metal ions doped rare earth oxides are dealt with. |
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