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Glass-ceramic nanocomposites comprising GdBr₃/CeBr₃ loaded sodium-aluminosilicate glasses in which scintillating crystallites are precipitated in situ from a host glass matrix were studied. This materials system shows promise as an alternative to single-crystal scintillators, with potential to be fabricated into a wide variety of sizes, shapes, and compositions. Batch compositions containing 15-18 mol. % GdBr₃ and 3-4 mol. % CeBr₃ were prepared and analyzed for photoluminescent light yield. Light yield peaked with rare-earth content of 15 mol. % GdBr₃ and 4 mol. % CeBr₃. Preliminary ceramization studies on this composition found that the precipitated phase more closely matched a Gd₂O₃-CeO₂ mixture rather than the GdBr₃(Ce) that was targeted.

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A glass wafer that contains cerium-activated gadolinium-based scintillator has been tested as a nuclear radiation monitor. The detector is prepared by mixing powdered gadolinium and cerium (3+) bromides with alumina, silica, and lithium fluoride, melting the mixture at 1,400°C, and then quenching and annealing the glass. The resulting clear glass matrix emits stimulated blue light that can be collected by a conventional photomultiplier tube. Spectral analysis of radionuclides with this detector shows the energy peaks for alpha particles, the energy continuum for beta particles, the Compton continuum and full-energy peaks for gamma rays, and an energy continuum with specific reaction-product peaks for neutrons. Energy resolution for the 5.5-MeV alpha particle and 0.662-MeV gamma-ray peaks is about 20%. This resolution, although threefold poorer than for single-crystal NaI(Tl) scintillators, contributes to radionuclide identification and quantification. Application of this detector to radiation monitoring is proposed, as well as approaches for improving light collection and energy resolution that will facilitate radionuclide identification and monitoring, especially for alpha particles, beta particles, and low-energy gamma rays.