Preparation Of Rare-earth Doped Oxysalt Phosphor And Its VUV-UV Spectrum Properties

The wide application of PDP has aroused the interest of the scientists on phosphors. In order to enhance the luminescent efficiency of PDP phosphors, the properties such as the host absorption band, the charge transfer state, the absorption of 4f5d and 4f4f states and the energy transfer in the systems have been studied. Though some progress has been achieved, the study is still far below systematization. The aim of the paper is mainly in research of the spectra and morphology properties of lanthanide ions in borates and aluminates and the relation between preparation methods and luminescent mechanism. The main results are obtained as follows.The VUV phosphors borates doped with Eu³⁺ are prepared by solid state method. BaZr(BO₃)₂ has a strong host absorption band, which indicates an efficient energy transition between the host and Eu³⁺ . The peaks in the excitation spectra of BaZr(BO₃)₂ is revealed. Doping with 3%mol Eu³⁺, the intensity of the spectra reaches the highest. The relation between luminescence intensity and concentration has been studied and it was commutative action that leads to the concentration quenching.The influence of Al and Si ions doping on the CTS, PPR and emission-excitation spectra is studied. Doping with Al₂O₃, the luminescence intensity increases greatly and the position of CTS has a red shift. When doping with 30%Al₂O₃, the luminescence intensity and PPR reach the highest. The increase of luminescence intensity is derived from the charge compensation of Al ion. The red shift of CTS results from the formation of two free electrons and the reduction of wave function coupling. Doping with Si, the luminescence intensity increases greatly. The CTS position has a red and blue shift, which is determined by the replacement. Doping with 20%Si, the luminescence intensity and PPR reach the highest. At last, we draw the conclusion that PPR has the same tendency with the intensity of CTS, not with its energy. The spectra doping with Pr is also studied. It is found that the 4f5d energy level of Pr is below that of 1S0 in BaZr(BO₃)₂. The enhancement of PPR in BaZr(BO₃)₂: Eu³⁺ : Pr results from the fold of the spectra.CaAl₂O₄:Eu²⁺ and BaMgAl10O17: Eu²⁺ are prepared by spray pyrolysis and SEM. XRD and the spectra in UV and VUV are studied. The results indicate that the rise in the heating temperature is beneficial to the purification of crystal. The addition of CTAB can reduce the surface tension and easily turn the samples to sphericity. On the other hand, the volatilization of CTAB in high temperature may lead to the change of the samples from sphericity to approximately hollow sphericity. The mechanism of concentration quenching of Eu²⁺in CaAl₂O₄:Eu²⁺ is commutative action and the best concentration of Eu²⁺ is 1%mol. Two preparation methods are compared and confirm that the spray pyrolysis may have an average spread of the particle size distribution, which will lead to the effective absorption of the sample.