Core-shell structured SiO2@YVO4:Dy3+/Sm3+ phosphor particles: sol-gel preparation and characterization

J Colloid Interface Sci. 2006 Aug 1;300(1):176-82. doi: 10.1016/j.jcis.2006.03.052. Epub 2006 Mar 27.

Abstract

Spherical SiO(2) particles have been coated with YVO(4):Dy(3+)/Sm(3+) phosphor layers by a Pechini sol-gel process, leading to the formation of core-shell structured SiO(2)@YVO(4):Dy(3+)/Sm(3+) particles. X-ray diffraction (XRD), Fourier-transform IR spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as lifetimes were used to characterize the resulting SiO(2)@YVO(4):Dy(3+)/Sm(3+) core-shell phosphors. The obtained core-shell phosphors have perfect spherical shape with narrow size distribution (average size ca. 300 nm), smooth surface and non-agglomeration. The thickness of shells could be easily controlled by changing the number of deposition cycles (20 nm for one deposition cycle). The core-shell particles show strong characteristic emission from Dy(3+) for SiO(2)@YVO(4):Dy(3+) and from Sm(3+) for SiO(2)@YVO(4):Sm(3+) due to an efficient energy transfer from YVO(4) host to them. The PL intensity of Dy(3+) and Sm(3+) increases with raising the annealing temperature and the number of coating cycles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gels
  • Luminescence*
  • Microscopy
  • Molecular Probes / chemical synthesis
  • Nanoparticles / chemistry*
  • Silicon Dioxide / chemistry*
  • Spectrum Analysis
  • X-Ray Diffraction
  • Ytterbium / chemistry*

Substances

  • Gels
  • Molecular Probes
  • Silicon Dioxide
  • Ytterbium