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8361169 
Journal Article 
Color tuning of Y3Al5O12 : Ce phosphor and their blend for white LEDs 
Kottaisamy, M; Thiyagarajan, P; Mishra, J; Rao, MSR; , 
2008 
1 
Materials Research Bulletin
ISSN: 0025-5408 
PERGAMON-ELSEVIER SCIENCE LTD 
OXFORD 
1657-1663 
WOS:000257365900005 
Gadolinium or lanthanum co-doped (0.5 mole) yttrium aluminum garnet doped with cerium phosphors were synthesized by a citric acid gel method and the effect of co-dopants on the structural and luminescent properties were studied. A significant peak shift in the photoluminescence spectra of yttrium aluminum garnet doped cerium was observed from 535 to 556 and 576 nm for gadolinium or lanthanum co-doped phosphors, respectively. The color tuned phosphor were blended with yttrium aluminum garnet doped cerium which showed a considerable improvement in the Commission International De Eclairage chromaticity co-ordinate values of gallium nitride based blue light emitting diode pumped white light. White light emitted from yttrium aluminum garnet doped cerium shows a Commission International De Eclairage value of (0.229, 0.182) whereas the yttrium aluminum garnet doped cerium phosphor blended with gadolinium or lanthanum co-doped phosphor shows (0.262, 0.243) and (0.295, 0.282), respectively. These results demonstrate the possibility to use these phosphor blends to enhance the white light generation in the field of white-light emitting diode solid-state lighting. (c) 2007 Elsevier Ltd. All rights reserved.