Preparation And Characterization Of One-dimensional Core-shell Structure Rare Earth Oxide And Fluoride Luminescent Nanomaterials

Recently, rare-earth luminescence materials have been paid more and more attention for their application in the fields of lighting, display and optical communications.Because one-dimensional nanometerials have low dimension and high surface-volume ratio, they show special optical、electronaland magnetic properties. The intensities of the luminescence nanomaterials would be reduced by the surface effects. The One-dimensional luminescence meterials coated with layers of undoped materials can reduce surface defects of luminescence nanometerials and improve the photoluminescence properties. In the thesis, one-dimensional rare-earth nanometerials were synthesized by hydrothermal, precipitation and double crucible method. Some significant results were as follows:(1) One-dimensional core-shell structural Gd2O3:Eu3+@Y2O3nanorods with different shell thickness were prepared by hydrothermal method. It was found that when the coating thickness was suitable, molar ratio of Gd2O3:Eu3+@Y2O3R=4:1. the lumicescence intensities of core-shell nanorods was higher than that of Gd2O3:Eu3+core nanorods.(2) One-dimensional Gd2O3:Eu3+@Y2O3nanorods were synthesized by homogeneous precipitation method. The diameter of coated samples was about15-25nm, the length was about100nm, the thickness of the coating was about4-5nm. Photoluminescence properties showed that the luminescence intensities of core-shell composite nanorods were higher than that of the Gd2O3:Eu3+core nanorods.(3) Core-shell structural Y3O3:Eu3+@SiO2@Gd2O3nanorods were prepared by hydrothermal method combined with precipitation method. The order of the photoluminescence intensity was Y2O3:Eu3+> Y2O3:Eu3+@Gd2O3> Y2O3:Eu3+@SiO2Y2O3:Eu3+@SiO2@Gd2O3.(4) One-dimensional YF3:Eu3+nanorods were prepared by double crucible method. The diameter of uncoated samples was70-75nm, the length was about1μm. Core-shell structural YF3:Eu3+@GdF3was prepared by precipitation method. The diameter of the coated samples was85-90nm, the thickness of the core-shell nanorods was about10nm. The lumicescence intensities of one-dimensional core-shell structural YF3:Eu3+@GdF3nanorods with different shell thickness were compared.