High-efficiency YAG:Ce~(3+) glass-ceramic phosphor by an organic-free screen-printing technique for high-power WLEDs

摘要

Y3Al5O12:Ce3+ glass-ceramic phosphor (YAG-GC), as a high thermal stability material, provides an efficient way to resolve the aging of phosphor-converted white light-emitting diodes in the high-power field. In the present work, transparent YAG-GCs are successfully prepared via a novel organic-free screen-printing route. The results reveal that the degradations of YAG phosphors are negligible in the as-prepared glass ceramic material. Favorable transmittance is achieved and the value is near 50%. The PL spectra intensities of YAG-GCs increase with increasing YAG doping concentration and film thickness. Superior thermal stability (87.9% of the initial value at 150 degrees C) and high quantum efficiency of 88.91% (decreased only 2.33% compared with the YAG raw materials) are obtained. The LE of YAG-GCs increases, while the CCT and CRI decrease with increases in film thicknesses and YAG doping concentrations. A high LE of 150.1 lm/W and an acceptable CCT of 5836 K, a CRI of 67.6 are achieved in YAG-GCs. All the results indicate that the as-prepared YAG-GCs are promising candidates in the field of high-power WLEDs.