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Nano Rare Earth Luminescent Materials Y_2O_3

Author: WuHuaiZuo
Tutor: YouFangTian
School: Beijing Jiaotong University
Course: Optics
Keywords: Y2O3: Eu3 Lu2O3 Nano Rare Earth Luminescent Materials Core-shell structure Lattice matching
CLC: TB383.1
Type: Master's thesis
Year: 2011
Downloads: 164
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Abstract

Rare earth luminescent materials now widely used in flat panel displays, lighting, optical communications and laser devices and other fields. Although rare earth luminescent materials and nano-materials have many advantages compared to, but still mainly commercialized phosphor particles with micron-level-based. The main reason is because: the nano-particle emitting surface effects (such as space, an unsaturated bond, a dangling bond, defects, etc.) will be generated by the quenching efficiency drops to emit light; also very easy Nanoparticles Some absorption of the excitation light absorption, or quenching the excited activator ions and ionic groups, they will cause the light emitting efficiency. Therefore, it proposed luminescence of rare earth doped nano-particle surface modification to improve their luminescent properties; usually used in the material surface coated with a layer of other materials to form a core-shell structured nanoparticles to achieve this objective. In this paper we chose red fluorescent material at the nano Y2O3: Eu3 coated core-shell structure Lu2O3 for purpose of the study was to investigate the lattice matching and activator ions do not spread under the conditions as well as different cladding cladding thickness may impact on the Luminescence. The main research work is as follows: (a) prepared by homogeneous precipitation red fluorescent material Y2O3: Eu3 nano-spherical particles, and through XRD, SEM and fluorescence spectra analysis and discussion of the different pH values and different amounts of surfactant and different annealing temperature on the Y2O3: Eu3 morphology and glowing effect, determine the appropriate preparation conditions: 1. When the reaction solution pH = 7, the resulting product is spherical, when pH = 6 and 8, the products were rod-shaped and sheet; 2 in the amount of surfactant nRE3 / nCATB = 1:0.5, when compared to the grain sample obtained with relatively good good premise spherical shape and a uniform particle size distribution; 3. With the annealing temperature, the sample tends to be good crystallinity, but the samples prepared at high temperature annealing occurs agglomeration, thereby destroying their morphology and structure of nano-, 800 ℃ annealed samples under one hour can be obtained at the desired nanosphere Morphology of the case to ensure that materials better crystallinity. (2) homogeneous precipitation method using Y2O3: Eu3 nm spherical particles coated on the surface modification layer Lu2O3, and by SEM, EDX characterize other tests to verify the existence of the phenomenon coated. Followed by the analysis of the fluorescence spectra and lifetime of the luminescence properties of coated materials, and found that, after the cladding Lu2O3, longer life light emitting material, the light emitting performance is improved. Coated according to the type and thickness of the final preparation Y2O3: Eu3 @ Lu2O3 luminous performance analysis, found that when the reaction process n (Y Eu) 3: nLu3 is 1:1, the luminescence is best, considering the Y2O3 : Eu3 nucleus with a particle size distribution range in the actual reaction will Lu2O3 separate nucleation factors, such as errors after the reaction the ratio cladding layer material but is relatively good so that modification of the Y2O3: Eu3 surface, thereby improve the luminescent properties of the material.

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