Morphology control of Gd₂O₃:Eu phosphor particles with cubic and monoclinic phases prepared by high-temperature spray pyrolysis

Gd₂O₃:Eu phosphor particles with cubic and monoclinic phases were directly prepared by high-temperature spray pyrolysis from aqueous, polymeric precursor and colloidal solutions. The colloidal solution with nanosized silica was effective for the preparation of Gd ₂O₃:Eu phosphor particles with a cubic phase, a high photoluminescence intensity and a good morphology. The phosphor particles prepared from colloidal solutions with nanosized silica obtained by hydrolysis had a small size, a narrow size distribution, a spherical shape and a filled morphology. The optimum doping concentration of nanosized silica particles was 0.5 wt % of the product particles. The phosphor particles prepared by spray pyrolysis from colloidal solutions at temperatures below 1580°C had the photoluminescence spectrra of the cubic phase and a maximum photoluminescence intensity at a temperature of 1560°C.