Photoluminescence characteristics and energy transfer mechanism of Eu3+:NaY(WO4)2 microparticles

Abstract

A series of red emitting phosphors Eu3+:NaY(WO4)2 were successfully synthesized through conventional hydrothermal reactions. Meanwhile, the photoluminescence characteristics of Eu3+:NaY(WO4)2 microparticles were detailedly discussed. The XRD measurements demonstrate that all products exhibited pure phase as NaY(WO4)2 and doping Eu3+ ions did evoke change the crystal parameters of matrix material. The SEM and TEM images show that the particle morphology was quasi-cubes with uniform appearance and the size was about 3–4 µm. Microparticles of Eu3+:NaY(WO4)2 can observe emissions located at 594 nm and 618 nm while excited by near-UV (249 nm) and near-IR (797 nm). And the energy transfer mechanism between Eu3+ was proved to be electric dipole–dipole (d–d) interaction as well as the critical distance was calculated to be 9.936 A. What’s more, the phonon sideband spectra of Eu3+ ions was used to calculated Huang-Rays factor and analyze the phonon energy. Subsequently, for self-generated quenching process of Eu3+ occurs was well explained according to Auzel’s theoretical model. Besides, the CIE color coordinates of Eu3+:NaY(WO4)2 phosphors exhibited the ideal red chromaticity.