Crystal structure and luminescence properties of a cyan emitting Ca10(SiO4)3(SO4)3F2:Eu2+ phosphor

Europium-doped apatite Ca10(SiO4)3(SO4)3F2 (CSSF) has been successfully synthesized by solid state reaction. The crystal structure of CSSF:0.006Eu2+ is refined by the Maud refinement method. Optical properties of the prepared samples are found to depend on the rare-earth metal–oxygen distances and lattice iconicity. The excitation spectra of the CSSF:Eu2+ phosphors centered at 350 nm and covered the range from 250 to 450 nm. Under 350 nm excitation, the emission spectra of CSSF:Eu2+ phosphors show a blue (centered at 420 nm) and a green (centered at 525 nm) emission band, respectively. Meanwhile, the concentration quenching and energy transfer mechanism have been investigated via the configuration coordinate diagram. The key parameters, such as the temperature-dependent photoluminescence and CIE values of the CSSF:Eu2+ phosphor have also been studied.