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.

Thermal and Mechanical Properties of Nd³⁺/Yb³⁺ Co-Doped Titanate Glass with Upconversion Emissions

“…Thermal differential analysis was carried out to characterize the thermal stability [10][11][12][13][14][15] by Netzsch STA 449C thermoanalyzer in the experiments. The amorphous structure of TLZ glasses prepared by levitation method has been identified by Bruker D8 Advance X-ray diffractometer (XRD).…”

“…It was obvious that the variation of Nd 3 + content had no significant effect on the values of Tg, Tc, and Tp in the investigated scope. Tg was estimated as high as~1093 K, much higher than that of fluoride or oxy-fluoride glasses which was usually lower than 700 K. 13,14 Therefore, the upconversion devices based on this glass might be used more widely for technological application. On the other hand, the values of Tc and Tp were 1168 and 1177 K, respectively.…”