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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%).

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Phosphate glasses doped with Dy[Formula: see text] ions and containing silver nanoparticles (SNPs) were synthesized in the present work. We report photoluminescence characterization by absorption and emission spectra. The effect of Ag concentration on the thermoluminescence (TL) glow curves was studied. The scanning electron microscopy (SEM) shows the formation of SNP. Absorption spectra of the samples show the influence of the SNP in the bands 350[Formula: see text]nm at 425[Formula: see text]nm associated with the Dy[Formula: see text], in the same spectra we can see the bands 750, 800, 875, 1098, 1278[Formula: see text]nm and 1675[Formula: see text]nm belonging to the Dy[Formula: see text]. Emission spectra show two prominent bands at 480[Formula: see text]nm and 574[Formula: see text]nm and one faint band at 665[Formula: see text]nm corresponding to 4F[Formula: see text]H[Formula: see text], 4F[Formula: see text]H[Formula: see text] and 4F[Formula: see text]H[Formula: see text] transitions, respectively. All bands under 364[Formula: see text]nm pumping, and the fluorescence in the 550[Formula: see text]nm and 590[Formula: see text]nm spectral range enhanced four times. The Commission Internationale de 1’Eclairage (CIE) color coordinates were evaluated from the emission spectra to simulate white light emission from the phosphate glasses. The photostability of the samples was also studied in the UVA (315–403[Formula: see text]nm) and UVB (280–315[Formula: see text]nm) ranges. TL due to ultraviolet radiation (UVR) was studied; the glow curves show significant dependence of the TL intensity with the increment of SNPs in the samples. These results show the phosphate glasses doped with Dy[Formula: see text] and containing SNP as a potential candidate have to be used in solid-state illumination and retrospective dosimetry.