Synthesis and photoluminescence of Eu3+- or Tb3+-doped Mg2SiO4 nanoparticles prepared by a combined novel approach

Tb3+- or Eu3+-doped magnesium silicate phosphors were prepared for the first time by using a novel approach, combined sol-gel-microwave heating. X-ray diffraction (XRD), transmission electron microscope (TEM), thermogravimetric analysis (TGA) and photoluminescence analyses were used to characterize the phosphors. XRD confirmed a forsterite lattice of Mg2SiO4 for the phosphors. TEM observation indicated that the phosphors have a spherical-like shape with little aggregation and the particle size is about 50 nm, and the small size is favorable to the potential application in field emission displays. The luminescent colors of Mg2SiO4:Tb3+ and Mg2SiO4:Eu3+ phosphors are green and red respectively, furthermore the luminescent intensities of them are relatively higher than the traditional Zn2SiO4:Tb3+ and Zn2SiO4:Eu3+ phosphors. In addition, Eu3+ ion emissions as a structural probe suggest that the rare earth ions replace the Mg2+ ions in the site of M2 (Cs) in the forsterite lattice of Mg2SiO4.