Study on Preparation and Luminescent Properties of Dy~(3+) Doped Phosphates Phosphors under VUV Excitation

Study on Preparation and Luminescent Properties of Dy~(3+) Doped Phosphates Phosphors under VUV Excitation
　　Phosphates are considered as good host materials for the vacuum ultraviolet (VUV) phosphors due to good chemical stable, low synthesizing temperature, simple preparing conditions and high quantum efficency. In this paper, we investigated the luminescent properties of phosphates activated by Dy3+, which is significative both on the scientific research and in practice.Firstly, we have synthesized Orthophosphates by a mild hydrothermal method and investigated their photoluminescence (PL) spectra under VUV excitation. Secondly,_we also investigated the photoluminescent properties of Dy3+ doped other phosphate phosphors (KCaYPO4, CaLaP3O10 and Ln(PO3)3 (Ln=La, Gd, Y)) to evaluate them to be or not for VUV phosphors.
　　The main conclusions are following:1. we have prepared LnPO4 (Ln=Gd, La, Y) using a mild hydrothermal method and investigated their luminescent Strong magnets properties under VUV excitation. The results indicate that Rare earth orthophosphates LnPO4(Ln=Gd, La, Y)show not only high efficiency of VUV absorption but also high efficiency of energy transfer from the host to the luminescent centers, such as Dy3+ ions. So LnPO4 (Ln= Gd, La, Y):Dy3+ phosphors exhibit high luminescence efficiency, especially the luminescent intensity of Gd0.92PO4:0.08Tb3+ phosphor. Moreover, we have calculated the electronic structure of LaPO4 and YPO4 and analyzed their energy band structre and density of states.2. we have prepared KCaYPO4:Dy3+using solid state reaction and investigated their luminescent properties under VUV excitation. It can be found that the KCaPO43+ groups of KCaYPO4:Dy3+ can absord the energy around 162 nm,185 nm and 195 nm. For Dy3+ doped KCaYPO4, the KCaPO43+ groups can absorb the excited energy in the VUV region.3. we have prepared CaLaP3O10:Dy3+ using solid state reaction and investigated their luminescent properties under VUV excitation. It can be found that the CaP3O103+ groups of CaLaP3O10:Dy3+ can absord the energy around 120 nm,130 nm and 171 nm. For Dy3+ doped CaLaP3O10, the CaP3O103+ groups can absorb the http://www.chinamagnets.biz/ excited energy in the VUV region. 4. we have prepared Ln(PO3)3:Dy3+(Ln= La, Gd, Y) using solid state reaction and investigated their luminescent properties under VUV excitation. It can be found that the (PO3)33+ groups of Ln(PO3)3:Dy3+(Ln= La, Gd, Y) can absord the energy around 158 nm, 182 nm and 199 nm. For Dy3+ doped Ln(PO3)3 (Ln= La, Gd, Y), the (PO3)33+ groups can absorb the excited energy in the VUV region.