Synthesis and photoluminescence properties of Sm3+ and Dy3+ ions activated Ca2Gd2W3O14 phosphors

Rare earth ions (Sm3+ and Dy3+) activated calcium gadolinium tungstate [Ca2Gd2W3O14] powder phosphors were synthesized by solid state reaction method at 1000 degrees C. The obtained phosphors were characterized by XRD, SEM, EDAX, FTIR and PL spectroscopy. The results of XRD patterns indicate the tetragonal phase structure of Sm3+ and Dy3+: Ca2Gd2W3O14 phosphors. From the SEM images of Sm3+ and Dy3+: Ca2Gd2W3O14 phosphors, it is observed that the average grain size is in the range 100-250 nm. The functional groups are identified by using the FTIR spectra and the elements present in the composition are confirmed by the EDAX profiles. Emission spectra of Sm3+: Ca2Gd2W3O14 powder phosphors have shown strong red emission at 646 nm ((4)G(5/2) -> H-6(9/2)) with an excitation wavelength lambda(exci) = 402 nm (H-6(5/2) -> F-4(7/2)) and Dy3+: Ca2Gd2W3O14 phosphors have shown yellow emission at 574 nm (F-4(9/2) -> H-6(13/2)) with an excitation wavelength lambda(exci) = 385 nm (H-6(15/2) -> I-4(13/2)). (C) 2011 Elsevier B.V. All rights reserved.