title: Molten salt synthesis, visible and near-IR region spectral properties of europium or neodymium doped CoNb2O6 columbite niobate.
abstract: Pure Nd(3+)- or Eu(3+)-doped CoNb2O6 powders have been prepared by a molten salt synthesis method using a Li2SO4-Na2SO4 or NaCl-KCl salt mixture as a flux at relatively low temperatures as compared to the solid state reaction method. X-ray diffraction patterns of pure CoNb2O6 samples indicated an orthorhombic single phase. For Eu(3+)-doped CoNb2O6 samples, the luminescence of Eu(3+) was observed at 615 nm as red emission while the Nd(3+) doped sample showed a typical emission at 1064 nm varying with the Eu(3+) or Nd(3+) doping concentrations. These luminescence characteristics of the doped samples may be attributed to the energy transfer between rare earth ions and CoO6 octahedral groups in the columbite structure.
authors.affiliation: Marmara University, Art and Science Faculty, Chemistry Department, Inorganic Chemistry Division, Istanbul, Turkey. asbasak@marmara.edu.tr mekmekci@marmara.edu.tr.
authors.forename: Mete Kaan
authors.initials: MK
authors.lastname: Ekmekçi
authors.forename: Murat
authors.initials: M
authors.lastname: Erdem
authors.forename: Ali Sadi
authors.initials: AS
authors.lastname: Başak