Synthesis, luminescence and OSL dosimetric characteristics of NaLi 2 PO 4 :Ce 3+ phosphor

A series of NaLi2PO4:Ce3+ phosphor was synthesized using a modified solid-state method. The structural and morphological characteristics were analyzed through XRD (X-ray diffraction) and SEM (Scanning Electronic Microscope). Identification of elemental composition of materials was completed through Energy Dispersive X-Ray Analysis (EDX). The PL excitation and emission spectra of prepared NaLi2PO4:Ce3+ were monitored at λEm = 358 and λEx = 312 nm respectively. OSL decay curve of the phosphor was deconvoluted in three exponential decay curves. The phosphor demonstrated superior OSL sensitivity, being 4.6 times more than α-Al2O3:C (BARC) phosphor, with minimum detectable dose (MDD) ∼14 µGy. The effective atomic number of NaLi2PO4:Ce3+ phosphor (Zeff = 10.8) is less than Zeff of α-Al2O3:C phosphor (Zeff = 11.28). The phosphor shows linear OSL dose response in the dose range of 0.6 mGy to 30 Gy and fading of the OSL signal was found to be about 40% in 1 day, stabilizing thereafter. The TL glow curve of NaLi2PO4:Ce3+ phosphor consists of overlapping peaks in the temperature range of 50°C to 400°C. The TL glow curve was deconvoluted, and the kinetic parameters, like life time, activation energy and frequency factor were evaluated by the TL glow curve deconvolution method. TL dose response is linear in the dose range of 0.6 mGy to 30 Gy and TL glow curve at various heating rate shows good thermal stability with negligible thermal quenching. The findings suggest that the synthesized phosphor is suitable for personal monitoring and environmental monitoring applications.