Synthesis and photoluminescence properties of Y 1− x (P 0.6 V 0.4 )O 4 : x Eu 3+ red-emitting phosphors

Y 1− x (P 0.6 V 0.4 )O 4 :xEu 3+ phosphors with different dopant concentration of Eu 3+ ( x = 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.10, 0.13, 0.15) have been synthesized via chemical coprecipitation method. The consequent phosphors were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), infrared spectroscopy, photoluminescence excitation and emission spectra. The results of XRD indicate that the samples belong to tetragonal system, and Eu 3+ are successfully doped into the lattice without changing the lattice structure. Infrared spectroscopy reveal that all polyphosphates and polyvanadates are transformed to orthophosphates and orthovanadates, respectively. Under excitation wavelength at 350 nm, the emission spectra exhibit the 5 D 0 → 7 F J ( J = 0–2) transitions belonged to Eu 3+ ions in the region of 400–650 nm. Compared with YPO 4 :Eu 3+ phosphors, the introduction of VO 4 3− into the matrix, which corresponding to the intensity of Eu 3+ 5 D 0 → 7 F 2 transition located at 619 nm, and emitting pure red light, can be significantly increased. The emission intensity of the phosphors first reach the maximum when the concentration of Eu 3+ is 0.05, and then decreases with increasing of Eu 3+ ions concentration, this is resulting from concentration quenching caused by the reabsorption effect. The results indicate that the obtained phosphors have a certain application as red light emitting phosphors in ultraviolet-pumped white light-emitting diodes (LEDs).