Synthesis And Luminescence Properties Research Of Micro/Nano-rare Earth Fluoride

In this thesis, the fluoride nano/micro luminescent materials with Rare earth doped were synthesized by the microemulsion method and oleic acid assisted solvothermal method,using CaF₂ as host lattices. The concrete contents include following aspects:1. CaF₂: Yb³⁺, Tb³⁺ nanoparticles have been successfully prepared via a simple and mild microemulsion route. X-ray diffraction, scanning electron microscopy, and photoluminescence spectra were adopted to characterize the as-prepared samples, the results indicated that the nanoparticles were single phase and spheric morphology, the average size was about 68.4 nm. The UC emission spectrum of the CaF₂: Yb³⁺, Tb³⁺ nanoparticles under the excitation of 980 nm showed the characteristic peaks of Tb³⁺ion,we also analyzed the upconversion mechanism and process.2. Nanoparticals of CaF₂: Tb³⁺were prepared by microemulsion method. X-ray diffraction?XRD? and scanning electron microscopy indicated that the nanoparricals were cuibc phase CaF₂ nanoparticals and spheric morphology, the average size was about 59.5nm. which is belonging to the cubic system. Fluorescence spectra showed that the nanoparticals of CaF₂: Tb³⁺can be effectively excited by 216 nm, and emit green light, the emission peaks of Tb³⁺ ion located at 492 nm?5D4?7F6?, 542 nm?5D4?7F5?, 582nm?5D4?7F4?, 617 nm?5D4?7F3?. The effect of doping concentration and Ce³⁺ion co-doping were studied on the luminescence properties of the nanoparticles: when the doping content of Tb³⁺ion was 7 mol %, the nanoparticle emit the strongest luminescence, the emission intensity of the nanoparticals can be increased by co-doping the Ce³⁺ ion, and the optimum doping content of Ce³⁺ion was 3 mol%, namely, Ce³⁺ion can directly tansfer the absorbed energy to Tb³⁺ ion, which enhance the luminescence intensity of Tb³⁺ ion.3. CaF₂: Tb³⁺, Eu³⁺were prepared by oleic acid assisted solvothermal method, X-ray diffraction, scanning electron microscopy, and photoluminescence spectra were adopted to characterize the as-prepared samples, the results indicated that the nanoparticles were single phase and irregular spheric morphology, the average size was about 1.6 ?m. The processes of Tb³⁺?Eu³⁺energy transfer were discussed in detail.