Two Steps Synthesis And Luminescence Properties Of Rare Earth Ions Doped Fluoride Up-conversion Materials

Illumination, fluorescent labeling, display and other fields of technology have been increasingly mature with the development of the era and technology, and further requirements have put through by people about the light-emitting materials widely used in these areas, for instance, high cost performance, high efficiency and low pollution rate. So, the rare earth doped light-emitting up-conversion material has attracted many attentions of the scholars at home and abroad in the field of luminous and spectroscopy, and the new preparation methods have been put forward at the same time. However, the outstanding luminous performance and a suitable grain size for the application will determine if the material has a good application. Therefore, the real challenge lies in preparation methods is the control of morphology of the material to enables the rare earth ions to produce efficient luminescence. In numerous up-conversion properties, fluoride is particularly prominent with its strong ionic fluoride, optical good permeability, low phonon energy, strong insulation, chemical stability and other good characteristics. In this paper, Er3+ and Yb3+ doped fluoride up-conversion phosphors were prepared using two step synthesis method by combining combustion method and high temperature solid phase method and their physical property, chemical property, light performance were studied. The conclusions as follows:(1).The optimum preparation conditions of Er3+ and Yb3+ doped fluoride up-conversion phosphors using two step synthesis method by combining combustion method-high temperature solid phase method were studied, and found that the condition is:Glycine(GLy):Ln3+=1.5;Solid phase temperature 500 ℃; Doping amount of NH4HF2 is double that of equivalent, and compare the differences of structure and morphology between different materials by using X-ray diffraction (XRD), scanning electron microscope (SEM).(2).The luminescence properties of Er3+ and Yb3+ doped fluoride up-conversion phosphors were studied by using fluorescence spectrum method, energy transfer dynamic of the doped Er3+ and Yb3+ and up-conversion mechanism were analyzed. Found the red light emission and green light emission in different samples were two photon processes.(3).The influence of the change of solid phase temperature and the quantity of doped fluoride source on the fluoride up-conversion phosphors luminescence were discussed by comparing the calculated color coordinates of the samples prepared under different experimental conditions and combining with the optical properties of them.(4).The quenching phenomenon of Er3+ and Yb3+ doped fluoride up-conversion phosphors depend on temperature is studied, that is, how up-conversion luminescence is affected by temperature and how the temperature rise effect is caused by pump power.