Luminescence properties of white-light long-lasting phosphor Y2O2S:Dy3+, Mg2+, Si4+

A series of novel Y2O2S:Dy3+, Mg2+, Si4+ white-light long-lasting phosphors were synthesized by the solid-state reaction method. The Y2O2S:Dy3+, Mg2+, Si4+ phosphors were characterized by X-ray diffraction, photoluminescence and long-lasting phosphorescence spectra, and thermoluminescence curves. The samples doped with different concentrations of Dy3+ ions were composed of the pure Y2O2S phase. Under 357 nm UV excitation, the emission peaks at 486 nm and 577 nm were assigned to the F-4(9/2)-->H-6(15/2) and F-4(9/2)-->H-6(13/2) transitions of Dy3+ respectively. When Dy3+ concentration was 1%, the CIE chromaticity diagram was (0.28, 0.28), and the decay time could last for over 36 min (>= 1 mcd/m(2)). (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.