Luminescence and Energy Transfer of Tb3+/Dy3+ Co-Doped SiO2-Al2O3-B2O3-La2O3-Gd2O3 Glasses

Tb3+/Dy3+ co-doped glass with host system of SiO2-Al2O3-B2O3-La2O3-Gd2O3 were prepared by melt-quenching method. The photoluminescence occurred under the transitions, D-5(3), D-5(4) -> F-7(J) of Tb3+ and F-4(9/2) -> H-6(J) of Dy3+ doped in glass. The emission spectra showed various transitions from the excited Tb3+, Dy3+ and Gd3+ ions which were calculated the color of emitted light and displayed in CIE diagram. The mixing emission of Tb3+ and Dy3+ (lambda(ex) = 376 nm and 349 nm) performed the yellowish-green color, while the energy transfer from Gd3+ (lambda(ex) = 270 nm) made Tb3+ and Dy3+ generating the white light. The energy transfer processes between Tb3+, Dy3+ and Gd3+ ions were verified by the excitation and emission spectra. The photoluminescence decay times of Tb3+ and Dy3+ in this glass are in millisecond order. The light yield of glass under excitation with 5.50 MeV of alpha particles were investigated and compared to Bi4Ge3O12 (BGO) crystal. This work could be useful for light source medium and radiation detection material.