Silver lead borate glasses doped with europium ions for phosphors applications

Abstract

Europium \((\hbox {Eu}^{3+})\) doped silver lead borate glasses with the composition of \(x\hbox {Eu}_{2}\hbox {O}_{3}{-}(1-x)\hbox {Ag}_{2}\hbox {O}{-}29\hbox {PbO}{-}70\hbox {B}_{2}\hbox {O}_{3}\) (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol%) have been successfully prepared by conventional melt quenching method. Thermal, structural and luminescence properties have been studied using thermograms, transmittance, excitation and emission spectra. From the differential scanning calorimetry studies, the glass transition temperatures \((T_\mathrm{g})\) have been investigated and their values are ranging from 449 to 458\({^{\circ }}\hbox {C}\). The investigation of Fourier transformer infrared spectra shows the presence of boron atoms in both \(\hbox {BO}_{3}\) and \(\hbox {BO}_{4}\) units in the glass network. In addition, it was found that new structural groups were present, such as boroxyl rings, pyro and dipenta-borate. Photoluminescence spectroscopy was used to examine down conversion emission under 394 nm excitation, which exhibits five emission bands centred at 577, 590, 612, 650 and 697 nm corresponding to \(^{5}\hbox {D}_{0}{-}^{7}\hbox {F}_{0}\), \(^{5}\hbox {D}_{0}{-}^{7}\hbox {F}_{1}\), \(^{5}\hbox {D}_{0}{-}^{7}\hbox {F}_{2}\), \(^{5}\hbox {D}_{0}{-}^{7}\hbox {F}_{3}\) and \(^{5}\hbox {D}_{0}{-}^{7}\hbox {F}_{4}\) transitions of \(\hbox {Eu}^{3+}\) ions, respectively. The Commission International de I’Eclairage France 1931 chromaticity coordinates estimated from the emission spectra; it was shown that a 0.5 mol% \(\hbox {Eu}_{2}\hbox {O}_{3}\) doped glass is quite suitable for efficient red phosphors application.