RE-doped semiconductor nanocrystals and full-color phosphor synthesis

Title: RE-doped semiconductor nanocrystals and full-color phosphor synthesis and properties of
　　Author: Xu Chaofa
　　Degree-granting units: Shantou University
　　Keywords: full color light emission;; Zn_2SiO_4;; photoluminescence;; nano-ZnO;; nano SnO_2
　　Summary:
　　Prepared by hydrothermal method were doped panchromatic Zn2SiO4: Ti, Mn, Eu luminescent powder, SnO2: Eu3 + nanocrystals, ZnO: Eu3 + (0.5.at.%) nanocrystals. X-ray diffraction (XRD), fluorescence spectrometer for analysis, Neodymium Magnets study of light pink and light-emitting properties of the crystal structure.
　　Prepared by hydrothermal method at different doping concentrations Zn2SiO4: Ti, Mn, Eu series phosphor, different doping concentrations of Zn2-xSiO4: xTi4 + series of phosphors and white phosphor Zn2SiO4: Ti, Mn, Eu series. XRD showed that the samples are pure phase zinc-blende structure of silicon Zn2SiO4. Fluorescence analysis showed that: Zn2-xSiO4: xMn2 + Series LED powder excitation spectrum by the Zn2SiO4 matrix absorption and Mn2 + charge transfer band composed of emission spectra from the Mn2 + in 4T1-6A1 transition emission formation, Zn2-xSiO4: xMn2 + luminescence intensity with Mn2 + doping concentration increased with the increase, when the sample doping concentration higher than 3.0 at.% when the concentration quenching. Zn2-xSiO4: xTi4 + excitation spectrum by a series of samples belonging to Ti4 + charge transfer excitation band with a wide composition and emission spectra originated in the 2E-1T Ti4 + transition. When Ti4 + doping concentration in the 2.5at.% When the concentration quenching. Through the regulation of different doping concentration to achieve a En, Mn, Ti co-doped powder Zn2SiO4 white light emission.
　　Hydrothermal synthesis of SnO2: Eu3 + nanocrystals, and this sample at different temperatures of heat treatment. XRD experiments show that the samples were prepared from pure phase rutile structure of SnO2. Sample of particles with heat treatment temperature increases. Spectral studies have shown that heat treatment after the excitation spectrum http://www.everbeenmagnet.com/en/products/110-sintered-neodymium-magnets of the sample containing Eu3 + in addition to the characteristics of the ff transition excitation peaks but also have O2 - Eu3 + charge transfer band, but not heat-treated sample does not appear charge transfer band, luminous intensity is inversely proportional to heat treatment temperature .
　　Hydrothermal synthesis of ZnO: Eu3 + (0.5.at.%) nanocrystals were achieved by changing the experimental conditions completely controlled nanocrystal size. XRD analysis showed that the samples are pure phase wurtzite structure of ZnO. The smaller the particle, the larger the sample of luminous intensity, after heat treatment, ZnO: Eu3 + (0.5.at.%) nanocrystal luminescence intensity significantly decreased, the emission peak red shift.
　　Degree Year: 2010