Novel synthesis and optical characterization of phosphor-converted WLED employing Ce:YAG-doped glass

In this work, a novel environmentally friendly strategy toward phosphor-converted WLED employing Ce:YAG-doped glass via single-step low-temperature co-sintering technology was successfully synthesized, using low-cost PbO-B2O3-SiO2-ZnO glass as host, which showed good sintering behavior and high visible transparency under the sintering condition of 750 °C without noticeable interaction with phosphors. By simply changing thermal condition, phosphor doped concentration and specimen thickness for the viscous sintering of phosphor in glass (PiG), optical characterization of WLED can be easily tuned. As a result, it can be found that the ideal thermal condition is sintered at 700 °C for 40 min, the optimal amount of phosphor powder is controlled to be 5 wt% of the final mixture, and the best suitable thickness of specimens is 0.8 mm. The constructed PiG based WLED exhibits a high luminous efficiency of 134.33 lm/W, and a correlated color temperature of 4696 K as well as a color rendering index of 68.5. Enhanced thermal quenching property of PiG compared to phosphor with conventional silicone resin reveals the prominent feasibility of the present glass ceramic material in WLED application. © 2015 Elsevier B.V. All rights reserved.