Synthesis and luminescence properties of Na3YSi2O7:Sm3+ phosphor

Novel Na3YSi2O7:Sm3+ phosphors for white light-emitting diodes (w-LEDs) were prepared by a conventional high-temperature solid-state reaction. X-ray diffraction, photoluminescence spectra and temperature-dependent emission spectra were utilized to characterize the structure and luminescence properties of the synthesized phosphor. The phosphor can be efficiently excited by the near-UV light, and emit red orange light. The emission spectra contain exclusively the characteristic emission of Sm3+, namely, (4)G(5/2) -> H-6(5/2) (564 nm) (4)G(5/2) -> H-6(7/2) (583 nm) (4)G(5/2) -> H-6(7/2) (609 nm) and (4)G(5/2) -> H-6(9/2) (651 nm). It was found that the critical quenching concentration of Sm3+ in the Na3YSi2O7 host is about 3 mol % and concentration quenching is ascribed to dipole dipole interaction according to Dexter's theory. The chromaticity coordinates (x, y) of Na3YSi2O7:0.03 Sm3+ phosphor are calculated to be (0.5449, 0.4472). The current research suggests that Na3YSi2O7:Sm3+ is a potential candidate for application in w-LEDs. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.