Conversion of LiF-based thermoluminescent dosimeters into photoluminescent dosimeters via Dy doping

Mg- and Dy co-doped LiF nanophosphors were fabricated using a chemical co-precipitation method and characterized for their application potential as thermoluminescent (TL) and photoluminescent (PL) dosimeters. X-ray diffraction revealed the formation of almost single phase cubic LiF:Mg, Dy with an average crystallite size of ∼35 nm. The TL glow curve consisted of a single peak in the temperature range 130–162 °C for different doses. The linearity and fading of these dosimeters were tested for 2 to 415 h. For these dosimeters, the minimum detectable dose was 40 mSv while the maximum detectable dose was  ⩾10 000 mSv. The PL emission peaks occurred at 687 nm (red emission) and their intensity increased with increasing Dy³⁺ concentration. Furthermore, the observed transfer of energy from Mg to Dy demonstrated that the excitation spectra of these nanophosphors could be controlled, suggesting the possibility of conversion of TL into PL dosimeters. (paper)