The luminescence and structural characteristics of Eu3+-doped NaBaPO4 phosphor

Eu3+-doped NaBaPO4 was prepared by a high-temperature solid-state reaction. The phase formation was confirmed by X-ray powder diffraction measurements. The laser site-selective excitation and emission spectra have been investigated in the 5D0 → 7F0 region by using a pulsed, tunable and narrowband dye laser. The excitation spectra corresponding to the 7F0 → 5D0 transition consist of two transitions at 579.6 nm Eu(I) and 578.9 nm Eu(II), indicating the Eu3+ ions occupy two crystallographic sites of Ba2+ ions. The decay lifetimes of the two Eu3+ sites were measured. Two crystallographic sites for Eu3+ ions doped in NaBaPO4 lattice were assigned from the luminescence characteristic and structure features. Meanwhile, the charge compensation mechanism of Eu3+ doping in NaBaPO4 was discussed.