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Oxyfluoride glass-ceramics have become a focal point of recent research, positioned to advance significantly in areas such as LED illumination and optical data storage, etc. This study successfully prepared Pr3+-doped fluorosilicate glass and glass-ceramics embedded Na 5 Y 9 F 32 nanocrystals. The introduction of Pr 2 O 3 into the glass matrix disturbs the network structure, leading to a reduction in the band gap from 3.66 eV to 3.42 eV. When subjected to 443 nm light excitation, the 1.0 mol% Pr3+-doped glass-ceramics crystallized at 690 °C for 1.0 h exhibit the most potent luminescence, displaying seven emission peaks resulting from the radiative transition of Pr3+ ions, manifesting yellowish-pink hues. Furthermore, when stimulated by a 450 nm LD, the glass-ceramics display a distinct emission peak at approximately ∼247 nm, attributed to the electron transitions of 4 f 5 d → 3H 4 for Pr3+ ions. The luminescent properties of these glass-ceramics embedded with Na 5 Y 9 F 32 nanocrystals illustrate potential applications in up-conversion and down-conversion luminescence. • A novel Pr3+ doped SiO 2 –Al 2 O 3 –Na 2 O-NaF-YF 3 glass-ceramics was successfully prepared. • Glass-ceramics containing Na 5 Y 9 F 32 crystals exhibit efficient excitation under blue light. • The glass-ceramics exhibit yellowish-pink hues excited by 443 nm light. • The glass-ceramics presents impressive emission peaks at ∼247 nm excited by 450 nm LD. • The work stresses glass-ceramics' huge potential in up-/down-conversion luminescence. [ABSTRACT FROM AUTHOR]

Luminescent glass-ceramics has garnered significant attention within the research community owing to its exceptional characteristics, including robust chemical stability, outstanding thermal stability, and efficient thermal conductivity. However, persistent challenges include issues related to suboptimal luminous efficiency and color rendering index. In the context of this research endeavor, we have achieved a noteworthy achievement by successfully fabricating a novel variant of glass-ceramics doped with both Eu2+ and Eu3+ ions within the Na 2 O-CaO-SiO 2 system glass. This innovative glass-ceramics composition encompassed Na 4 Ca 4 Si 6 O 18 crystals, characterized by grain sizes <110 nm. Our investigations, featuring comprehensive optical spectra analysis and detailed morphological examinations, have provided substantial evidence indicating the preferential occupation of Eu3+ ions in the Ca2+ sites residing within the Na 4 Ca 4 Si 6 O 18 crystal lattice, conversely, it is possible that the distribution of Eu2+ ions occurred within the glass matrix. Additionally, it is worth noting that this glass-ceramic material demonstrated a heightened excitation efficiency when subjected to 464 nm blue light, surpassing its performance with 393 nm violet light. Detailed fluorescence spectral analysis unveiled the impressive internal quantum efficiency of the glass-ceramics, reaching an impressive 80.27%, and this glass-ceramics exhibited remarkable fluorescence thermal stability at 150 °C, preserving approximately ∼75% of its luminescent intensity at room temperature. Furthermore, we have encapsulated the white light-emitting diode (W-LED) device, integrated with a 460 nm LED chip, optimized glass-ceramics, and YAG: Ce3+ phosphor. The outcomes were characterized by the warm white-light emission, suitable chromaticity coordinates, a high color rendering index (approximately 85.4), and impressive luminous efficiency (up to 112.47 lm/W). In summary, these findings unequivocally underscore the substantial potential of glass-ceramics in the realm of high-power W-LED lighting applications. • A novel Eu3+/Eu2+ co-doped Na 2 O-CaO-SiO 2 glass-ceramics was successfully prepared. • Glass-ceramics containing Na 4 Ca 4 Si 6 O 18 crystals exhibit efficient excitation under blue light. • The glass-ceramics presents impressive IQE (80.27%) and excellent thermal stability. • The encapsulated W-LED device exhibits high CRI, and impressive luminous efficiency. • The work emphasizes the huge potential of glass-ceramics in high-power W-LED lighting. [ABSTRACT FROM AUTHOR]