Bright Transparent Scintillators with High Fraction BaCl : Eu Nanocrystals Precipitation: An Ionic-Covalent Hybrid Network Strategy toward Superior X-Ray Imaging Glass-Ceramics.

Metal halide crystals are bright but hygroscopic scintillator materials that are widely used in X-ray imaging and detectors. Precipitating them in situ in glass to form glass ceramics (GCs) scintillator offers an efficient avenue for large-scale preparation, high spatial resolution, and excellent stability. However, precipitating a high fraction of metal halide nanocrystals in glass to maintain high light yield remains a challenge. Herein, an ionic-covalent hybrid network strategy for constructing GCs scintillator with high crystallinity (up to ≈37%) of BaCl : Eu nanocrystals is presented. Experimental data and simulations of glass structure reveal that the Ba -Cl clustering promotes the high crystallization of BaCl nanocrystals. The ultralow phonon energy (≈200 cm ) of BaCl nanocrystals and good Eu reduction effect enable high photoluminescence inter quantum efficiency (≈80.41%) in GC. GCs with varied crystallinity of BaCl : Eu nanocrystals demonstrate efficient radioluminescence and tunable scintillator performance. They either outperform Bi Ge O single crystal by over 132% steady-state light yield or provide impressive X-ray imaging resolutions of 20 lp mm . These findings provide a new design strategy for developing bright transparent GCs scintillators with a high fraction of metal halide nanocrystals for X-ray high-resolution imaging applications.