Abstract: A new Sm³⁺ doped yttrium oxysulfide phosphor, which has the long-lasting phosphorescence, was synthesized by flux fusion method. The phosphors showed three typical transitions of Sm³⁺ ( ⁴G_5/2→ 6H J, J=5/2,7/2,9/2), and the emission peaks located at 570, 606 and 659 nm respectively. A prominent luminescence and phosphorescence in orange-red can be seen in this phosphor when illuminated with UV light or visible light. The synthesized phosphors were characterized by X-ray diffraction, the excitation and photoluminescence spectra, and the after-glow intensity decay curve. The result shows that the Y₂O₂S∶ Sm³⁺ phosphor is another efficient orange-red phosphor.

Key words: Long-lasting phosphor, Yttrium Oxysulfide, Samarium ion