Chemical co-precipitation synthesis and photoluminescence of LnPxV1-xO4:Dy3+ (Ln = Gd, La) derived from assembling hybrid precursors

A novel synthesis technology was applied to obtain GdPxV1-xO4:Dy3+ (x=0.2, 0.3, 0.4, 0.5, 0.6, 0.7) and LaPxV1-xO4:Dy3+ (x=0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8) phosphors for the first time. And the doping concentration of Dy3+ ions was 3 mol.% in the two systems. Besides this, GdVO4 and LaVO4 doped with different concentration of Dy3+ ions were also synthesized. The rare earth coordination polymers with salicylic acid were used as precursors and the polyethylene glycol (PEG) was used as dispersing media. By an in situ co-precipitation process, we obtained the hybrid precursors. Both XRD and SEM indicated that the particles present good crystalline state, whose crystalline grain sizes were in the range of around 0.5-1 mu m. The optical properties of all the powder presented that the characteristic transitions of Dy3+ due to F-4(9/2) -> H-6(15/2) (blue) and F-4(9/2) -> H-6(13/2) (yellow) were detected. Besides this, in the system of GdPxV1-xO4:Dy3+, the yellow-to-blue intensity ration (Y/B) depended on the value of P/V greatly, with the increasing of x value, the Y/B decreasing. (c) 2006 Elsevier B.V. All rights reserved.