White emission from Dy3+ doped Gd2O3-B2O3 glass for WLEDs encapsulation

Novel bell-shaped glasses were fabricated to study the electro-luminescence properties of the glasses for LED applications. The physical and optical properties of Dysprosium (Dy3+) doped G(2)O(3)-B2O3 glasses were synthesised using the standard melt quenching procedure with com-positions of 27.5Gd(2)O(3)-(72.5-x)B2O3-xDy2O3 (where x = 0.05, 0.1, 0.5, 1.0, and 1.5 mol%). The highest emission intensity of Dy3+ doped Gd2O3-B2O3 glasses was found to be at 0.5 mol% (by 275 nm excitaiton of Gd3+ ion) and 1.5 mol% (by 350 nm excitation of Dy3+ ion) of Dy2O3 concentration. A bright yellow emission corresponding to the transition F9/2 & RARR; H13/2 (at 576 nm) was found in the emission spectra. This emission band was a mix of blue, yellow, and red. Furthermore, the CIE chromaticity diagram for glass 0.5 mol% Dy2O3 with color coordinates x = 0.368, y = 0.405, and shows white emission. The decay profiles were investigated for 575 emission and values show decreasing trend with increase in Dy2O3 content. Encapsulation of fabricated glasses were made to embed on top of the LED to investigate electro-luminescence spectra. From all results, this glasses could be used for LED encapsulation.