High color-purity broad orange-red emission of Mn²⁺-doped transparent phosphate glass-ceramics embedded NaYP₂O₇ crystals

In this work, novel Mn2+-doped transparent NaYP2O7 glass-ceramics were prepared through melt-quenching and subsequent thermal treatment. The surface crystallization method was confirmed based on the differential scanning calorimeter, X-ray diffraction, and scanning electron microscope characterization. As the increase and prolong of the heat-treatment temperature and time, the crystallinity of the NaYP2O7 glass-ceramics increases, while the transmittance gradually decreases. The optimal heat-treatment regime is identified to be crystallized over 4 h at 580 degrees C based on the crystallinity and transmittance. Under the excitation of 408 nm, both the Mn2+-doped precursor glass and glass-ceramic crystallized at 580 degrees C for 4 h generate a broad emission at 620 nm (T-4(2)(g)->(6)A(1)(s)) with a full width at half-maximum (FWHM) of similar to 107 nm. The glass-ceramics exhibit higher emission intensity and longer decay lifetime than that of precursor glass with the aid of the low phonon energy NaYP2O7 crystals. The Mn2+-doped glass-ceramic exhibits stable orange-red luminescence with the chromaticity coordinates of (0.568, 0.428), low correlation color temperature of 1 800 K, high color purity of 98.88%, and low thermal quenching (70% at 373 K of the initial intensity at 298 K). The above results indicate that Mn2+-doped transparent NaYP2O7 glass-ceramics have promising potential for orange-red color display devices.