Y₂SiO₅:Ce phosphor particles 0.5-1.4 μm in size with spherical morphology

Ce-doped Y₂SiO₅ phosphor particles with spherical morphology, small size, high crystallinity, and good photoluminescence (PL) intensity were prepared by spray pyrolysis. The characteristics of prepared particles were compared with those of commercial ones. The particles annealed above 1000°C had a clear crystallinity of Y₂SiO₅, and the crystal structure changed from X₁ to X₂ type after annealing above 1200°C. The mean size of the particles increased from 0.5 to 1.4 μm when the overall solution concentrations were varied from 0.045 to 0.9 mol/liter. The photoluminescence intensity and crystallinity of particles increased as the particle size and preparation temperature were increased. The annealed particles larger than 0.8 μm maintained a spherical morphology. Emission of blue light was observed after annealing above 1000°C on excitation with an UV light. The PL spectra particles annealed below 1100°C had maximum values at 450 nm, and shifted to the smaller wavelengths after annealing above 1200°C. The brightness of particles increased with increasing annealing temperatures due to favorable crystallization and had a maximum at 1400°C. The particles annealed above 1400°C exhibited intensities higher than those of particles produced commercially.