Enhanced luminescence intensity and color purity of the red emitting LnVO4:Eu3+@SiO2 (Ln = Gd, Y and Gd/Y) powder phosphors

An attempt was made to enhance the luminescence properties of LnVO(4):Eu3+@SiO2 (Ln = Gd, Y and Gd/Y) powder phosphors. Pure phase with tetragonal structure of the produced phosphors was confirmed by XRD profiles. Sub-micron sized phosphors have shown 35% more PL intensity than the bulk, which was further improved 20.22% with SiO2 shell coating. SiO2 shell coating was optimized by SEM-EDAX, FT-IR, PL and TEM measurements. Emission intensities of the transition, D-5(0) -> F-7(2) have dominated D-5(0) -> F-7(1) which indicated the lowering of an inverse symmetry in the vicinity of Eu3+ ions. Luminescence intensity and color purity were enhanced with the host modification by substituting Gd3+ with Y3+ sites, followed by SiO2 coating. Based on the systematic investigations carried out, the phosphor Y0.95VO4:Eu-0.05(3+)@SiO2 is suggested to be a novel contender for its suitable red emission in certain displays or lighting. (C) 2012 Elsevier Ltd. All rights reserved.