Luminescent properties of rare-earth (Eu3+, Eu2+ and Ce3+) doped apatitic oxyphosphosilicates

Abstract The luminescence of (Eu 3+ , Ce 3+ and Eu 2+ ) doped apatitic phosphosilicates is studied at either 300 and 77 K. Samples of Ca 5 La 5 (SiO 4 ) 3 (PO 4 ) 3 O 2 :Ln(2%) where Ln=Eu 3+ , Ce 3+ and Eu 2+ , were synthesized by solid-state reaction at high temperature (1400°C) and then identified by the X-ray diffraction method. The rare-earth cations were found to occupy two cationic sites labeled M(I) and M(II) with a local symmetry C 3 and C s , respectively. In comparison with Ce 3+ or Eu 2+ -doped apatitic phosphates, the bands observed in the emission spectra of Ca 5 La 5 (SiO 4 ) 3 (PO 4 ) 3 O 2 :Ce 3+ (2%) and Ca 5 La 5 (SiO 4 ) 3 (PO 4 ) 3 O 2 :Eu 2+ (2%) were found to be shifted to higher wavelength.