This study explores the influence of varying Europium oxide (Eu2O3) concentrations on the physical, structural, optical, and luminescence properties of boro-tellurite glasses. Glass samples were synthesized via the melt-quenching technique with Eu2O3 concentrations ranging from 0 to 3 mol%. Analytical techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and photoluminescence (PL) spectroscopy, were employed. Results revealed a increase in density and decreased molar volume with higher Eu2O3 content, indicating network expansion due to the larger ionic radius of Eu3+ ions. FTIR confirmed the presence of BO3 and BO4 units, with increased BO4 proportions suggesting the role of Eu³⁺ ions as network modifiers. Photoluminescence studies showed characteristic emissions of Eu³⁺ ions, with the maximum intensity observed at 1.5 mol% Eu2O3 before concentration quenching occurred. Judd-Ofelt analysis demonstrated high asymmetry in the Eu3+ local environment, while CIE chromaticity coordinates highlighted a reddish-orange hue, suitable for white light-emitting diode (WLED) applications. X-ray-induced luminescence showed patterns consistent with photoluminescence, with the 1.5 mol% sample achieving 27.48% scintillation efficiency compared to a bismuth germanate (BGO) crystal. These findings underline the potential of Eu3+-doped glasses as gain media for lasers and as phosphors for WLEDs, especially in indoor lighting and scintillation applications.
Yasaka et al. (2025) studied this question.