PREPARATION AND CHARACTERIZATION OF UNIFORM, SPHERICAL-PARTICLES OF Y2O2S AND Y2O2S-EU

The preparation of spherical Y2O2S and Y2O2S:Eu particles using a soli d-gas reaction of monodispersed precursors with elemental sulfur vapor under an argon atmosphere has been investigated. The precursors, undo ped and doped yttrium basic carbonates, are synthesized by aging a sto ck solution containing the respective cation chloride and urea at 82-8 4 degrees C. Y2O2S and Y2O2S:Eu were characterized in terms of their c omposition, crystallinity and morphology by chemical analysis, X-ray p owder diffraction (XRD), IR spectroscopy, and scanning electron micros copy (SEM). The Eu-doped oxysulfide was also characterized by atomic a bsorption spectrophotometry and luminescence spectroscopy. The spheric al morphology of oxysulfide products and of basic carbonate precursors suggests a topotatic inter-relationship between both compounds.