Enhanced red and green emissions in Sr2GdF7-based nano-glass-ceramics through Ce3+ sensitization and energy migration

Transparent nano-glass-ceramics (nGCs) containing RE 3+ (Ce 3+ , Eu 3+ , Tb 3+ )-doped Sr 2 GdF 7 nanocrystals (NCs) were successfully synthesized through the controlled thermal treatment of precursor sol-gel glasses. The formation and uniform dispersion of tetragonal Sr₂GdF 7 NCs within the SiO₂ matrix were confirmed using X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). Efficient energy transfer (ET) from Ce³⁺ to the dopant ions, mediated by Gd³⁺ ions through a Ce³⁺→(Gd³⁺) n →RE³⁺ pathway, resulted in intense visible emissions. To further investigate the distribution of RE³⁺ ions within the nGCs, and validate the proposed ET pathways, additional solvothermal Sr 2 GdF 7 (Ce 3+ , Eu 3+ )-doped NCs, along with (Ce³⁺, Eu³⁺, Tb³⁺)-doped Sr₂YF 7 nGCs, were also synthesized, respectively. Comparative analyses of the structural and spectroscopic properties of these materials with their Sr₂GdF 7 -based counterparts were performed. These ET mechanisms were further confirmed through transient luminescence measurements. The results suggest that the investigated glass-ceramics hold promise as potential converters of UV to visible light for applications where an efficient photonic conversion is crucial. • RE 3+ -doped nano-glass-ceramics with cubic Sr 2 GdF 7 nanocrystals were obtained. • XRD, TEM and EDS confirm the precipitation and distribution of Sr 2 GdF 7 nanocrystals. • High energy transfer through Ce³⁺.→(Gd³⁺)n→RE³⁺ chain resulted in intense emissions • Results suggest potential applications as UV-VIS converters in the field of lighting.