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Lithium tetraborate (Li2B4O7) pellets prepared by using water/solution assisted method were synthesized and characterized. Copper was used as doping material in order to enhance the Li2B4O7 thermoluminescent properties. For synthesis heating temperature parameters were defined at 750 °C for 2 hr, followed by 150 °C for another 2 hr. The materials were produced at five different Cu concentrations: 0.02, 0.04, 0.06, 0.08, and 0.1 wt%. The luminescent and morphological characterizations were performed by X-ray diffraction (XRD), Scanning electron microscope (SEM), Photoluminescence (PL), and Ultraviolet-visible spectroscopy (UV-Vis). XRD and SEM analysis of intrinsic and doped materials confirmed the obtained Li2B4O7 structure and show its morphology. XRD patterns of the Li2B4O7 matched a tetragonal crystal structure. Crystals of Li2B4O7 of an average size of 50 nm were obtained. The presence of the copper dopant was confirmed in crystals of Li2B4O7:Cu by SEM-EDS (energy dispersive spectroscopy X-ray). The emission spectrum of Cu doped Li2B4O7 showed a prominent peak at 367 nm, while the main UV-Vis absorption was observed from 240 nm to 300 nm due to Cu+ ion 3d10 → 3d9 4s transitions. The thermoluminescent (TL) response was studied for both γ radiation and X-ray. A 661.7 keV γ radiation using a 137Cs source at doses of 50, 100, 200, 300, 400 and 500 mGy was applied to Li2B4O7:Cu (0.1 wt%) pellets. An X-ray source was used at doses of 600, 800 and 1000 mGy to irradiate pellets of Li2B4O7:Cu (0.02, 0.04, 0.06, 0.08 and 0.1 wt%). A linear TL response was observed for both X-ray and γ radiation. The kinetic parameters were calculated using the peak shape method for the Li2B4O7:Cu (0.1 wt%).

In this paper, the co-precipitation method was used to synthesize pure and Ag-doped LiF crystals and the effect of crystalline cube sizes and Ag concentration on the thermoluminescent (TL) response is reported. The synthesized materials were characterized by scanning electron microscopy and their morphology and size distributions were determined. Crystal sizes were found to be strongly dependent on the ethanol:water ratio, varying from 4.1[Formula: see text][Formula: see text]m to 150[Formula: see text]nm for pure LiF crystals. For Ag-doped samples, the best ethanol:water ratio was found to be 9:1, giving crystals from 0.50[Formula: see text][Formula: see text]m to 1.21[Formula: see text][Formula: see text]m. A single cubic crystalline phase was determined by XRD for all synthesized samples. The photoluminescence spectra as well as UV-Vis absorbance were also analyzed. The TL response to X-ray irradiation was studied for an exposition of 43[Formula: see text]R. Two effects were observed in the TL response. The first concerns with a significant dependence of the TL intensity on the size of the crystals, being larger for the smallest crystals for pure LiF, and second, for Ag-doped samples the TL intensity augmented almost linearly with the Ag concentration.