Tunable luminescence of Sn2+/Mn2+ codoped phosphate glasses for W-LEDs

The demands for white-light-emitting materials are becoming more and more rigorous. In this work, a novel kind of Sn²⁺/Mn²⁺ doped phosphate aluminum calcium glass was fabricated by a traditional melt-quenching technique. Broadband excitation and emission of Sn²⁺ ions were detected in Sn²⁺ single-doped glass samples. By the modulation of excitation wavelength, tunable broadband cyan-blue light emissions of Sn²⁺ were also realized. Combined with the red light emitting of Mn²⁺ ions, a nearly white light with a good chromaticity coordinate (0.339, 0.298) and a relatively low correlated color temperature (CCT) of 5107 K was obtained in Sn²⁺/Mn²⁺ codoped glasses due to the energy transfer process from Sn²⁺ to Mn²⁺ ions. In addition, after two cycles of heating and cooling treatment, the emission intensity of Sn²⁺ doped glass sample remained 97.9 % of the initial emission intensity at 300 K. All of these results reveal that these Sn²⁺/Mn²⁺ doped aluminum calcium phosphate glasses have good resistance to thermal impacts and have prospects in white-light-emitting diodes (W-LEDs) fields.