Preparation And Characterization Of Rare Earth Doped Bisumth Tungstate Luminescent Material

In this paper, Yb3+-Ho3+and Yb3+-Tm3+co-doped Bi2WO6nanocrystal phosphor were synthesized by hydrothermal method using PEG as dispersant. The effect of changing the experimental condition and the concentration of rare earth ions on the fabrication process and luminescence behavior was discussed.The samples were characterized by X-ray diffraction and scanning electron microscopy. Up-conversion luminescence spectra with980nm excitation wavelength of semiconductor laser as excitation source was used to study the luminescence properties. The work in the paper could be divided into two parts as followings:1. Yb3+-Ho3+co-doped Bi2WO6phosphor is a kind of orthorhombic structure nanocrystal with diameter of30nm. Visible emissions at546nm and655nm were observed and the maximum luminescent intensity was achieved when the concentration of Ho3+, Yb3+arrived at1.5mol%and9mol%, respectively.2. The diameter of Yb3+-Tm3+co-doped Bi2WO6phosphor is about35nm, and can be more than100nm after annealing. The481nm blue emission and the780nm near-infrared emission were found on the up-conversion emission spectrum. Two red emission peaks at653nm and691nm were also observed. The annealing technology showed that when the concentration of Tm3+, Yb3+arrived at1.0mol%and8mol%, after heating at600℃the luminous result were best.