Influence of Gd3+ on structural and luminescence properties of new Eu3+-doped borate glass for photonics material

Abstract

The Gd2O3–La2O3–ZnO–B2O3–Eu2O3 glasses with different Gd2O3 concentration (Gd:LaZnBEu) were studied in the physical, structural, optical and luminescence properties. The density and refractive index of glass increased with addition of Gd2O3 content. The FTIR spectra demonstrated the BO3 and BO4 borate complexes as the main construction in glass those were more disturbed by Gd2O3 increasing. The BO4/BO3 and bridging/non-bridging oxygen ratio, observed from XPS, changed by following the Gd2O3 concentration whose 10 mol% owned the highest values of both ratios. In the absorption spectra, glasses absorbed some photons in UV – NIR region. The excitation by O2−→Eu3+ charge transfer (240 nm), Gd3+→Eu3+ energy transfer (275 nm) and direct Eu3+ excitation (394 nm) caused the strongest Eu3+ photoluminescence at 613 nm (5D0→7F2). The glass with 5 mol%-Gd2O3, that possessed the optimum Eu3+ local site, exhibited the highest absorbance and photo-/radio-luminescence intensity. The CIE 1931 and UV lamp excitation revealed the strong reddish-orange emission of glasses. The photoluminescence decay time of Eu3+ in glasses were between 1.6 and 2.1 ms and decreased with added Gd2O3 amount. The Gd:LaZnBEu glasses have a potential for LED, laser, display, and X-ray detection devices with integration mode.