Research On Synthesis And Luminescent Properties Of Rare Earth Doped Near-Infrared And Red Fluorescent Materials

The applications of rare-earth doped luminescent materials are more and more widely and increasingly concerned by people.This paper sets about from the three places to carry on the exploration of rare-earth doped luminescent materials.First,the wavelength range of rare-earth doped near infrared luminescent material is between 700 nm to 2500 nm.In recent years,rare-earth doped near-infrared luminescent material reflects the very important application value on the analysis of biological sensors,solar cells,biological imaging technology,medical near infrared diagnostic technology and laser and optical fibre communication,but the study is also relatively little about it,and it has become a hot research topic.Second,poor stability and low luminous efficiency are the shortcomings of existing industrial red phosphors,and to study the new red fluorescent material has very important practical significance.Third,yellow long lasting phosphorescence materials that can be excitation by blue light are still scarce.To explore luminescent materials that can be excitation by blue light and has adjustable color of long lasting phosphorescence has important application significance.This paper selects yttrium aluminum garnet system and niobate system as hosts,and activator ions have Rn³⁺=Ce³⁺,Yb³⁺,Pr³⁺,Nd³⁺,Sm3+,Tb³⁺,Dy³⁺,Ho³⁺,Er³⁺,Tm³⁺and so on.All the samples were prepared by high-temperature solid-state method.We obtained the excellent samples,Gd_x Y_2.96-xGa₃Al₂O₁₂:0.04Ce³⁺（x=0.5,1.0,1.5,2.0,2.5,2.96）,Gd_xLu_2.96-xGa₃Al₂O₁₂:0.04Ce³⁺（x=0,0.5,1.0,1.5,2.0,2.5）,Y_x Lu_2.96-x.96-x Ga₃Al₂O₁₂:0.04Ce³⁺（x=0.5,1.0,1.5,2.0,2.5,2.96）,that had gradient long lasting phosphorescence in the synthetic experiments with yttrium aluminum garnet as host.These samples can emit from yellow to green and blue gradient color after the irradiation of xenon lamp with 254nm for 3 min,and the long lasting phosphorescence can last for about 5 hours.Also obtained excellent near-infrared samples,Gd_1.5YGa₃Al₂O₁₂:0.5Er³⁺,Gd_1.5YGa₃Al₂O₁₂:0.5Yb³⁺,Gd_1.5Y_1.49Ga₃Al₂O₁₂:0.1Nd³⁺.Properties of samples were investigated systematically by powder X-ray diffraction patterns,photoluminescence spectra,long lasting phosphorescence spectra,phosphorescence decay curves,and thermoluminescence spectra.We obtained the excellent single-doped red fluorescence sample Y_0.85Eu_0.15NbO₄,co-dopedredfluorescencesamplesY_0.85Eu_0.15Nb_0.98Zr_0.02O₄and Y_0.84Eu_0.15In_0.01NdO₄,in the synthetic experiments with niobate as host.Properties of samples were investigated systematically by powder X-ray diffraction patterns,photoluminescence spectra.