Luminescence properties of GdVO4 blue phosphors doped with Tb3+ ions.

Gd(1-x)VO4:Tb3+ phosphor powders were synthesized with different Tb3+ concentrations by using a solid-state reaction method. The effects of Tb3+ concentrations on the structural, morphological, photoluminescence, and photoluminescence excitation properties of the Tb(3+)-doped GdVO4 phosphors were investigated. XRD data exhibited that the main peak of the phosphors occurred at (200) plane. The increase of grain size and the hexagonal pattern in shape were observed with increasing the concentration of Tb3+ ion. As for the optical properties, two excitation spectra centered at 241 and about 315 nm were observed. The blue 5D4-7F6 emission at 486 nm reached the maximum when the concentration of Tb3+ ion was 15 mol% and the emission intensity rapidly decreased at 20 mol% due to the concentration quenching.