NaMgF3:Eu with improved OSL properties prepared by a simple solid-state method

Abstract

NaMgF₃:Eu is reported as a promising optically stimulated luminescence (OSL) material, but there are various shortcomings in the materials prepared by existing methods for personal and environmental dosimetry. This study aims to synthesize NaMgF₃:Eu phosphor with improved performance at the lowest possible preparation cost, and detailed characterize the material, including the basic OSL and thermoluminescence (TL) performances, OSL dosimetric properties for identification of the application fields. A simple solid-state method was adopted, and NaMgF₃:Eu phosphor was obtained with a desired phase, consistent radioluminescence (RL) spectrum with previous literature. The initial OSL intensity was 1.65 times that in the InLight dosimeter with a 5.33 times faster decay rate. OSL fading in this material has been significantly improved compared to previous studies with only a 19.56% reduction of the total OSL within 1 day after irradiation. The material exhibited excellent repeatability of 0.44% at the same dose delivery for 10 cycles, the optimal MDD of 0.28 µGy under the integration time of 1 s, and the linear OSL response over the tested dose range (0.1–10 Gy). The high OSL sensitivity, fast decay speed of OSL signals and excellent OSL dosimetric characteristics have demonstrated the potential of NaMgF₃:Eu for real-time OSL measurements in medical monitoring, and environmental and space dosimetry. Moreover, the relationship between OSL and TL and the luminous mechanism was also investigated using associated measurements and kinetics analysis of OSL with TL, which gives not only information on the origin of OSL but also guidance for further performance improvement in the future.