Luminescence of ZnS:Ag scintillator prepared by the hydrothermal reaction method: Effects of reaction temperature and time, Ag concentration, and co-doping with Al

Abstract ZnS:Ag was synthesized by the hydrothermal reaction method with different Ag concentrations, from 0.05 to 5 mol%, Ag, Al co-doping concentrations, from 0.025 to 0.5 mol% ea., and under broad ranges of reaction temperature, from 60 to 200 °C, and reaction time, from 2 to 10 h. Samples were characterized on their structure, morphology, and luminescence by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and radioluminescence under X-ray excitation (RL) measurements, respectively. SEM results suggested that nucleation and growth of ZnS:Ag occurred on the surface of microbubbles. XRD results also revealed the samples to have single cubic structure, and that crystallite size could be controlled within ca. 2–11 nm through specific combinations of reaction temperature and time. PL measurements revealed the contribution of distinct luminescence centers, and that blue/red emission could be tuned by the reaction conditions. It was found that PL and RL output was maximized with nominal 0.l-0.2 mol% Ag, and with nominal 0.1 mol% ea. Ag, Al co-doping.