Thermally and optically stimulated luminescence of new ZnO nanophosphors exposed to beta particle irradiation

In this work, we report on the thermoluminescence (TL) and the optically stimulated luminescence (OSL) of ZnO nanophosphors obtained by thermal annealing of ZnS powders synthesized by precipitation in a chemical bath deposition reaction. To obtain nanocrystalline ZnO, ZnS pellet-shaped samples were subjected to a sintering process at 700C during 24h exposed to air at atmospheric pressure. Some samples were exposed to beta particles in the 0.15-10.15kGy dose range and the integrated TL as a function of dose increased with dose level, with no saturation indication for the tested dose levels. Computerized glow-curve deconvolution of the experimental glow curves in individual peaks revealed a second-order kinetics. In order to test the OSL response, samples were irradiated with beta particles with doses up to 600Gy, and an increasing intensity as dose increased was observed. We conclude that the new ZnO phosphors under investigation are good candidates to be used as dosimetric materials.