Synthesis of Eu3+-activated yttrium oxysulfide red phosphor by flux fusion method

Synthesis of the yttrium oxysulfide red phosphor by the flux fusion method was presented. Effects of flux compositions and sintering conditions on the shape and size distribution of phosphor were studied. In addition, the optimization of firing conditions was also conducted. After firing phosphor with a flux containing (S+Na2CO3+Li3PO4+K2CO3)/(S+Li2CO3+K2CO3) at a ratio of 3:1 at 1150°C for 2.5 h, Y2O2S:Eu3+ phosphor was obtained without any Y2O3 as a second phase. The nearly spherical phosphor powder exhibited a mean particle size of 3 μm and a rather sharp particle size distribution. Y2O2S:Eu3+ red phosphor illuminated the most red color light with an applied probe current density of 0.51 μA/cm2.