Preparation and luminescence characterization of fine-sized LaSr2AlO5:Ce phosphor prepared by spray pyrolysis

Fine-sized (La1−x,Cex)Sr2AlO5 (LSA:Ce) yellow phosphor particles were prepared by spray pyrolysis. The crystal structure and optical properties of prepared LSA:Ce particles were studied by changing the reduction temperature and the Ce content. The LSA:Ce particles had spherical-like shape and fine size of less than ∼2 μm in the reduction temperature range from 1300 to 1450 °C. The luminescence intensity was steadily improved by elevating the reduction temperature due to the increase of crystallinity. A redshift in the emission peak was observed on increasing the Ce content due to the reduction of Ce–O distance. Concentration quenching in the luminescence intensity was observed when the Ce concentration was 1% (x=0.01), which was caused mainly by the electric dipole–dipole interaction. The critical transfer distance was calculated as 29 Å, which is in good agreement with the value estimated from the spectral data.