Enhanced luminescence in Tb3+-doped glass-ceramic scintillators containing LiYF4 nanocrystals

Abstract

Tb3+ ions single-doped transparent oxyfluoride glass-ceramics (GC) containing LiYF4 nanocrystals were prepared via a conventional high-temperature melt quenching way and subsequent further thermal-treatment. The microstructure and related luminescent properties of the composite materials were studied in detail. It was confirmed by XRD and TEM techniques that the precipitated particles in the glass phase of the GC590-4h sample were LiYF4 nanocrystals having a size of approximately 26 nm. Compared to the PG sample, the luminescence intensity of the GCs at 378 nm light excitation was significantly enhanced and the corresponding lifetime was prolonged. This is because the Tb3+ ions are preferentially enriched in the precipitated low-phonon-energy LiYF4 nanocrystals, which can effectively induce the reduction of non-radiative transitions. It is worth noting that the emission intensity of Tb3+ single-doped GCs containing LiYF4 nanocrystals at 545 nm (5D4→7F5) is also greatly improved (under X-ray excitation). The obtained results indicate that Tb3+ single-doped LiYF4 GC may have the potential to be a novel scintillator applied to X-ray detection for the slow event.