Sodium Carbonate Flux Effects on the Luminescence Characteristics of (Y 0.5 Gd 0.5 ) 2 O 3 :Eu Phosphor Particles Prepared by Spray Pyrolysis

Na 2 CO 3 flux was introduced in the preparation of phosphor particles by spray pyrolysis to improve the photoluminescence (PL) characteristics of (Y 0.5 Gd 0.5 ) 2 O 3 :Eu phosphor particles. The phosphor particles directly prepared by spray pyrolysis at 1300°C from solutions with 20 wt% Na 2 CO 3 flux had the highest PL intensity, which corresponded to 130% of that of particles prepared from solution without flux. On the other hand, the maximum PL intensity of the annealed particles, which were as‐prepared at 900°C and posttreated at 1200°C for 3 h, was obtained from a solution with 5 wt% Na 2 CO 3 flux. The maximum PL intensity of particles directly prepared by spray pyrolysis without posttreatment was 86% of that of posttreated phosphor particles. Na 2 CO 3 flux was also important in control of morphology of (Y 0.5 Gd 0.5 ) 2 O 3 :Eu phosphor particles.