Co-Precipitation Synthesis and Spectral Characteristics of Long Afterglow Phosphor Y2O2S:Sm3+, Mg2+, Ti4+

Y2O2S:Sm3+, Mg2+, Ti4+ phosphor was synthesized by co-precipitation method. The crystalline structure of all synthesized phosphors was investigated by XRD. The result showed that all synthesized phosphors had a hexagonal crystal structure, which was the same as Y2O2S. The emission spectrum and excitation spectrum were measured, and the effect of Sm3+ molar ratio on the spectra was discussed. The emission spectra of the phosphors showed three emission peaks due to typical transitions of Sm3+ (4G5/2→6HJ, J = 5/2, 7/2, 9/2), and the emission peaks at 606 nm was stronger than others. With the increase of Sm3+ molar ratio, the emission intensity was strengthened. The excitation peaks were ascribed to the representative energy transition 4f→4f of Sm3+ ions. The results indicated that the Y2O2S:Sm3+, Mg2+, Ti4+ phosphor prepared by co-precipitation method was an efficient long afterglow phosphor.