The influence of different conditions on the luminescent properties of YAG : Ce phosphor formed by combustion

Powder phosphor yttrium aluminum garnet (YAG), activated with trivalent cerium (Ce3+) is synthesized by combustion from mixed metal nitrate reactants and urea with ignition temperature of 500-550 degrees C. After repeated calcinations at a given temperature for 5 h, purephase phosphor was obtained. The experiment result shows the appropriate temperature for repeated calcinations is 1000 degrees C. Luminescent intensity at various quantity of urea is studied in detail and the maximum value shown in the result in fact is 2.5 times larger than the theoretical value. In addition, the characteristics of particles such as crystallinity, morphology and photoluminescence were investigated. There are two peaks in its excited spectrum and the major one is a broad band around 470nm, which matches the blue emission of GaN LED very well. The emission peak locates at about 532 nm, which can combine the blue light of GaN LED to yield white light. (c) 2006 Elsevier B.V. All rights reserved.