Luminescent properties of Eu3+ doped NaY(WO4)2 nanophosphors prepared by molten salt method

Tetragonal phase NaY(WO4)(2):Eu3+.phosphors were synthesized through a molten salt method. The X-ray powder diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) were utilized to characterize the crystal structure and morphology. The emission and excited spectra were used to study the photoluminescence properties. The results of XRD and FE-SEM indicated that the samples prepared by this method were pure phase and the particle size was about 50 nm. The PL results showed that Eu3+ (D0 -> F2)-D-5-F-7 red luminescence at 616.5 nm could be excited by 394.5 nm near-UV light and 465 nm blue light in NaY(WO4)(2) host effectively, and the quenching concentration was 30 mol.%. The critical energy transfer distance and J-O parameters were calculated. The energy transfer type between Eu3+ was proved. What's more, the quantum efficiencies of the D-5(0) level of Eu3+ were calculated as well.