The effect of flux materials on the physical and optical properties of Eu 3+-activated yttrium oxide phosphors

Abstract

A flux fusion method was used to obtain the various sizes of Eu 3+-activated Y 2O 3 red phosphors. The flux material was selected as an independent variable to control the physical properties of phosphor particles and their effects on the morphology and size distribution of phosphors were examined by scanning electron microscopy. The concentration of the flux materials and synthetic temperature were optimized for maximal photoluminescence intensity. Fluoride-based flux materials were found to work for the crystal formation of Eu 3+-activated Y 2O 3. In particular, when a BaF 2 flux was used during the reaction at 1450 °C for 3 h, the photoluminescence (PL) intensity of Eu 3+-activated Y 2O 3 was 25% higher than that without a flux and spherical phosphors had a mean particle size of 4–5 μm. The morphology and size distribution of the synthesized Eu 3+-activated Y 2O 3 phosphor were predominantly dependent upon the type and concentration of flux material and synthetic temperature.