Synthesis and characterization of novel red emitting nanocrystal Gd6WO12:Eu3+ phosphors

Novel nanosized Gd6WO12:Eu3+ phosphors were synthesized via a co-precipitation reaction. The crystal structure and morphology of the phosphors were characterized by using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). It was found that the resultant powders show a regular and sphere-like shape with average particle size of 60 nm. Intrinsic red emission originating from Eu3+ was observed while excited at the W6+-> O2- and Eu3+-> O2- charge transfer bands or f-f absorption bands. The color coordinates of the phosphors were calculated to be x = 0.625, y = 0.375. The concentration dependence of the luminescence was studied, and optimum doping concentration for obtaining maximum emitting intensity was confirmed to be around 12 mol%. It was also found that the electric dipole-dipole interaction plays an important role for quenching luminescence of Eu3+. (C) 2009 Elsevier B.V. All rights reserved.