Effects of NH₄Cl flux on the characteristics of yttrium oxide phosphor particles with a spherical shape

High brightness Y₂O₃:Eu phosphor particles with a spherical shape and fine size were prepared by spray pyrolysis from spray solutions with polymeric precursors, a drying control chemical additive and ammonium chloride flux. The phosphor particles prepared from the spray solution with the ammonium chloride flux had a hollow and porous structure after post-treatment. However, the phosphor particles prepared from the spray solution with polymeric precursors, a drying control chemical additive and ammonium chloride flux had a spherical shape and filled inner structure after post-treatment. The optimum content of the NH₄Cl flux showing the maximum photoluminescence intensity of the Y₂O₃:Eu phosphor particles was 6 wt%. The improvement of the photoluminescence intensity of the Y₂O₃:Eu phosphor particles by additions of ammonium chloride flux, polymeric precursors and a drying control chemical additive into the spray solution was 37%.