Direct synthesis of high-brightness (CeTb)MgAl₁₁O₁₉ phosphor particles by spray pyrolysis with boric acid flux

High-brightness (CeTb)MgAl₁₁O₁₉ (CTMA) phosphor particles were directly prepared by high temperature spray pyrolysis. The boric acid flux added into spray solution affected the morphology and photoluminescence intensity of the CTMA phosphor. The phosphor particles prepared from spray solution with 20wt% boric acid of the product had a spherical shape and a filled morphology at 1600°C. The phosphor particles prepared by spray pyrolysis from spray solution without flux material under reducing atmosphere at 1600°C had high photoluminescence intensities under ultraviolet. The boric acid flux improved the photoluminescence intensities of the CTMA phosphor. The maximum photoluminescence intensity of the phosphor particles prepared from spray solution with an optimum amount of added boric acid flux was 114% of that of the phosphor particles prepared from spray solution without flux material. The particles directly prepared by spray pyrolysis from spray solution with 20 wt % boric acid of the product had a pure crystal structure of the CTMA phosphor.