Effect of annealing on the luminescence properties of YVO4:Dy3+ phosphor on co-doping Pb2+ ions

Pb2+ co-doped YVO4:Dy3+ phosphors have been synthesized at a relatively low temperature of 120 degrees C via ethylene glycol route. The samples are further annealed at 500 and 900 degrees C. The prepared samples were characterized by XRD, SEM, spectra energy dispersive analysis of X-ray (EDAX) and photoluminescence spectroscopy. XRD patterns of all samples are well indexed with single tetragonal phase of YVO4. The emission intensity of Dy3+ is significantly enhanced on co-doping Pb2+ ions. The highest emission is obtained at 7 at.% Pb2+ for 900 degrees C annealed samples. Both emission intensity and decay lifetime increases on annealing the samples from 500 to 900 degrees C. On co-doping Pb2+ into YVO4:Dy3+ phosphors, the emission color falls near the white region and then shift towards yellow region on annealing from 500 to 900 degrees C thereby indicating that annealing temperature play a role on tuning the color of the phosphors. As well as the emission color of the phosphors remain the same even on changing the excitation wavelengths from 280 nm, which would serve as potential phosphors for white emission in LED applications. (C) 2015 Elsevier B.V. All rights reserved.