Green-emitting silicate phosphor under long wavelength ultraviolet prepared by high temperature flame spray pyrolysis

Green-emitting Ba_1.468Sr_0.5SiO₄: Eu_0.12,Y_0.02 phosphor powders under long-wavelength ultraviolet light were prepared via high-temperature flame spray pyrolysis from spray solutions with and without NH₄Cl flux. The effects of the temperature of the diffusion flame and the NH₄Cl flux on the morphologies, crystal structures and photoluminescence intensities of the Ba_1.468 Sr_0.5SiO₄:Eu_0.012,Y_0.02 phosphor powders were investigated. The phosphor powders obtained from the spray solution with the NH₄C1 flux had higher photoluminescence intensities compared to phosphor powders obtained from the spray solution without the flux. The photoluminescence intensity of the phosphor powders obtained from the spray solution without the flux decreased as the flow rate of the fuel gas increased. On the other hand, the photoluminescence intensity of the phosphor powders obtained from the spray solution with the flux increased as the flow rate of the fuel gas increased. The difference of in the phase purity and morphology of the powders affected the photoluminescence intensities of the phosphor powders.