The Thermal Stability of Ce0.67Tb0.33MgAl11O19 by SiO2-Coatingin Sol-Gel Processing

Abstract

SiO2-coated phosphors of Ce0.67Tb0.33MgAl11O19(CTMA) were prepared by the sol–gel method in order to enhance thermal stabilities. The phase structures, microstructures and luminescence properties were studied by the X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM) and fluorescence spectrometer respectively. The emission intensity of SiO2-coated Ce0.67Tb0.33MgAl11O19phosphor was little lower than uncoated phosphor. After baked at 600°Cfor 6h, the coated CTMA showed good thermal stabilities. The luminance performance of SiO2-coated phosphor is 93% compared with the unbaked CTMA, which is improved 10% in contrast to uncoated.