Photoluminescence properties of novel Eu2+-activated CaSi6N8O oxynitride phosphor for white LED applications

Abstract A series of novel Eu2+-activated CaSi6N8O greenish-yellow phosphors were synthesized via solid state reaction method. The synthesized CaSi6N8O:Eu2+ phosphors could absorb UV to near UV light. The emission spectra exhibited a broad greenish-yellow emission band when excited with a light of wavelength 405 nm. The emission spectrum shifted towards longer wavelength with increasing Eu2+ concentration. The emission intensity increased with the increasing Eu2+ concentration and the quenching concentration was found to be 0.1 mol. The observed results were explained by the energy transfer mechanism due to dipole–dipole interactions among Eu2+ ions. These novel greenish-yellow CaSi6N8O:Eu2+ phosphors could be considered as potential candidate for the white LED applications.