Tunable white light emission of rare earth ions doped single matrix SrAl₂Si₂O₈ phosphors

Abstract

Aluminosilicate phosphors have been successfully applied in laser technology and fluorescent lamps due to their high luminescence properties and excellent chemical stability. Consequently, research on novel aluminosilicate phosphors has a good application prospect. Rare earth (RE) ions doped SrAl₂Si₂O₈ phosphors were prepared by solid-phase method. Excited at 350 nm, the phosphor doped with Dy³⁺ ions emits a blue light peaking at 482 nm and an orange light peaking at 575 nm, respectively, and its optimum do** concentration is 0.8 at.%. At the NUV excitation of 377 nm, the phosphor doped with Tb³⁺ ions shows emission peaks at 489 nm, 544 nm, 585 nm and 623 nm, and the luminescence intensity is the strongest when the content of Tb³⁺ is 9 at.%. The concentration quenching mechanism of Dy³⁺ and Tb³⁺ RE ions is the electric dipole–dipole interaction. For SrAl₂Si₂O₈:Tb³⁺, Sm³⁺ phosphors, the energy transfer efficiency is 85.4%, and the mechanism is electric dipole–quadrupole interaction. For SrAl₂Si₂O₈:Dy³⁺ and SrAl₂Si₂O₈:Tb³⁺, Sm³⁺ phosphors, the best CIE coordinates are (0.275, 0.308), (0.316, 0.386). The consequences display that RE ions doped single matrix SrAl₂Si₂O₈ phosphors can achieve effective white light emission and have high application value in white LEDs.