Insight into luminescence properties of Li+ co-doped Sr2SnO4:Eu3+ phosphors by co-precipitation assisted hydrothermal synthesis

Abstract

Sr2SnO4:Eu3+ phosphors were prepared by a co-precipitation combined with hydrothermal method for the first time, and Li+ was introduced to improve its luminescence performance. X-ray diffraction analysis determined that Sr2SnO4:Eu3+, Li+ phosphors were successfully synthesized. The effects and mechanisms of Li+ doping on the luminescence properties of Sr2SnO4:Eu3+ were specifically discussed. At 260 nm excitation, the fluorescence spectra of the products were dominated by the 5D0-7F1 characteristic emission peak of Eu3+ at 598 nm, with the electric dipole transition 5D0-7F2 being distinctly lower than the magnetic dipole transition 5D0-7F1, indicating that Eu3+ selectively replaced the highly symmetrical defective sites of Sn4+. The luminous intensity and decay lifetime were significantly enhanced through co-doping Li+, which played an essential role as a charge compensator. The optimum doping concentration of Li+ was 7%. Finally, the color purity of Sr2SnO4:Eu3+, Li+ reached 99.9%, suggesting that it could be developed as a potential orange-emitting material for solid-state lighting.