Laser synthesis and luminescence properties of SrAl2O4:Eu2+, Dy3+ phosphors

A laser melting method has been developed for the synthesis of highly luminescent, long-lasting SrAl2O4:Eu2+, Dy3+ phosphors. The high temperature achieved in high-power density CO2 laser irradiation of mixtures of SrCO3, Al2O3, Eu2O3, and Dy2O3 enabled the one-step, fast synthesis of these phosphors in air at atmospheric pressure. X-ray diffraction, Raman spectroscopy, and scanning electron microscopy characterization studies reveal that the produced materials consist of monoclinic SrAl2O4 grains extensively surrounded by rare-earth ion-enriched grain boundaries. The photoluminescence properties of laser-produced SrAl2O4:Eu2+, Dy3+ materials are discussed. The results reported here suggest that this laser melting method is a promising route for the synthesis of ceramic phosphors. It is presented as an alternative to the conventional sol-gel and solid-state methods, which require the use of high-temperature furnaces, flux additives, and reducing atmospheres. (C) 2012 Elsevier Ltd. All rights reserved.