Effect of defects on the luminescence and scintillation property of yluag:Ce phosphors obtained by different synthetic routes

Abstract

Optimized YLuAG:Ce (Y0.600Lu2.364Al5O12:Ce0.036) phosphors were synthesized by three methods: nitrate-pyrolysis (NP), co-precipitation (CP) with ammonium hydrogen carbonate, and citrate-combustion (CC). Differences in the reaction process, crystallization, morphologies, photoluminescence (PL), and scintillant performance of the three kinds of phosphors were revealed and are explained using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), PL and thermoluminescence (TL) measurements and observations. Obvious differences in the emission bands and decay times of the different phosphors prepared were found and the differences were mostly caused by the defects either on the surface or in the bulk phase of the YLuAG:Ce phosphors powders. The recorded thermoluminescence spectra of the three kinds of phosphors show a different intensity and main glow peak positions. Additionally, the thermoluminescence spectra show that the synthesis methods induce defects in the phosphors. The defects result in strong trapping process effects and a high probability of radiative recombination between the trapped holes and electrons in the final phosphor powders that were obtained using the different synthesis routes. © Editorial office of Acta Physico-Chimica Sinica.