Luminescent properties of nanoparticles YPXV1−XO4:Dy phosphors

Phosphors of nanoparticles YPXV1−XO4:Dy3+ (0⩽X⩽1) have been prepared by a citrate sol-gel method. X-ray diffraction, transmission electron microscope (TEM), scanning electron microscope (SEM) and photoluminescence excitation and emission spectra were utilized to characterize the phosphors. The results of XRD showed that a solid solution formed in YPXV1−XO4:Dy3+ phosphor series from X=0 to X=1 with zircon structure. TEM and SEM studies revealed that the obtained YPXV1−XO4:Dy3+ nanocrystals appeared to be spherical with some agglomeration and their sizes ranged from 30 to 80 nm. Upon short ultraviolet excitation, the optical properties of all the powder presented that the characteristic transitions of Dy3+ due to 4F9/2-6H15/2 (blue) and 4F9/2-6H13/2 (yellow) were detected. Besides this, in the system of YPXV1−XO4:Dy3+, the yellow-to-blue intensity ratio (Y/B) depended on the value of P/V greatly, with the increasing of X value and the decreased Y/B value. The phosphor found to yield white light when the value of X in the range of X=0.775-0.85, the optimum concentration for Dy3+ is 1 mol% of Y in the host, and the emission intensity increased with the annealing temperature.