ALBERT

Description: White-light-emitting glass is a kind of potential bi-replacement of both phosphors and epoxy resin in high power white-light-emitting diodes (WLEDs) because of its high thermal conductivity and excellent thermal stability in aspect of luminescence, CIE chromaticity and transmittance. In this paper, a series of tunable white-light-emitting strontium borate (SBO) glass SBO:Tb 3+ ,Eu 3+ were prepared by conventional melt quenching method, and their luminescence properties were systematically studied through their photoluminescence excitation and emission spectra, decay curves and quantum efficiency. Intense white-light-emitting can be achieved by in situ mixing of yellowish green and reddish orange emissions from Tb 3+ and Eu 3+ respectively in single glass component SBO, and mixed white emissions can be tuned by Tb 3+ Eu 3+ energy transfer with the increasing concentration of energy acceptor Eu 3+ . The quantum efficiency of optimal glass SBO:10%Tb 3+ ,6%Eu 3+ was measured as 36.78%. And the excellent thermal stability of this glass can remain its luminescence intensity above 80% at the temperatures below 523 K. Its chromaticity shift is less than 0.01 at the temperature below 548 K, which is far smaller than that of commercial DS-200 and triple color white emitting phosphor mixture. Except all above, the transmittance of this glass hardly shows loss after thermal aging at 120 °C for 240 h, which is superior to the only remaining 58.8% transmittance of epoxy resin. The thermal conductivity of this glass is 0.65 W/mK much better than the 0.16 W/mK of epoxy resin. Based on above research results, SBO:Tb 3+ ,Eu 3+ glass is considered as a promising candidate for high-power WLEDs, thus a SBO-WLED is simply assembled by SBO:10%Tb 3+ ,6%Eu 3+ glass and 378 nm LED chip, that can present excellent luminescence performance with V =10 V, I =600 mA. This article is protected by copyright. All rights reserved.