Photoluminescence properties of novel blue-light excited orange-red phosphors Sr3Al2Si3O12:Eu2+

Abstract

Developing red phosphors for LEDs is highly demanded yet challenging. Herein, a novel Eu2+-activated orange-red phosphors Sr3-xAl2Si3O12:xEu2+ (SASO:xEu2+) (0 ≤ x ≤ 0.08, ∆x = 0.01) were successfully prepared by high-temperature solid-phase reaction. The phosphors all belong to the cubic crystal system, and the space group is Fm-3 m(225). Phosphors SASO:xEu2+ can be efficiently excited by wavelengths in the range of 420–500 nm and produces strong orange-red light emission at 618 nm. In phosphors SASO:xEu2+, the optimal doping concentration of Eu2+ is 0.06, and the Inokuti–Hirayama (I-H) model shows that the energy transfer between Eu2+ ions is mainly due to the dipole-dipole (d-d) interaction. The phosphors SASO:xEu2+ have excellent thermal stability, the fluorescence intensity of phosphor SASO:0.06Eu2+ at 418 K still maintains 69.57 % of the fluorescence intensity at room temperature. Phosphor SASO:0.06Eu2+ has a high luminescence quality with a color purity of 86.5 %, which exhibits bright orange-red emission under 450 nm illumination.