Cu+ emission in Li2BPO5 material for thermoluminescence dosimetry

In this study, Li₂BPO₅ doped with Cu and that co-doped with Mg are synthesized by the wet chemical technique and exposed to γ rays of ⁶⁰Co to determine their thermoluminescence (TL) properties. The X-ray diffraction technique shows the crystalline nature of the prepared material. The photoluminescence (PL) emission spectra of Li₂BPO₅:Cu phosphor show the strong prominent peak at 368 nm in the violet region of the visible spectrum due to the transition of 3d⁹4s¹ ? 3d¹⁰ of monovalent copper ion. The PL emission of Li₂BPO₅:Cu is enhanced by the addition of Mg. The TL glow curves of γ-irradiated Li₂BPO₅:Cu sample show one glow peak at 143°C, indicating that only one set of traps is being activated within the particular temperature range each with its own value of activation energy (E) and frequency factor (s). The trapping parameters associated with the prominent glow peak of Li₂BPO₅:Cu are calculated using the glow curve shape (Chen's) method. The release of hole/electron from defect centers at the characteristic trap site initiates the luminescence process in these materials. A linear TL response is observed in Li₂BPO₅:Cu in a long span of exposures. The sensitivity of Li₂BPO₅:Cu sample is observed to be 7.8 times that of (TLD-100) LiF:Mg, Ti.