Reseach On Sodium Yttrium Tungstate Powders Doped With Rare-Earth Ions

Using polyethylene glycol as Complexing agent, up-conversion luminescence nanocrystal NaY(WO4)2:Yb3+,Er3+and NaY(WO4)2:Yb3+,Tm3+was synthesized by hydrothermal method in this paper. Using XRD and SEM determined Yb3+-Er3+and Yb3+-Tm3+co-doped NaY (WO4)2is tetragonal crystal system, the particle size ranged from20nm to40nm and dispersed uniformly. The spectrum was measured with Hitachi F-4500spectrophotometer under980nm diode laser excitation. The results are as follows:The emission peaking of NaY(WO4)2:Yb3+,Er3+nanocrystal located at410nm,524nm,553nm656nm corresponding to2H9/2â†'4I15/2,2H11/2â†'4I15/2,4S3/2â†'4I15/2and4F9/2â†'4I15/2transitions of Er3+, respectively. The results show that luminous result is best when concentration ratio of Yb/Er is4:1, doping concentration of Er3+ions is1.5mol%and treatment temperature is600℃. Bblue emission peak, green and red emission peak are the two-photon process, and the pertinent up-conversion mechnism model of the sample were proposed.The emission peaking of NaY(WO4)2"Yb3+,Tm3+nanocrystal located at365nm,456nm,476nm and648nm corresponding to1D2â†'3H6,1D2â†'3F4,1G4â†'3H6and1G4â†'3F4transitions of Tm3+, respectively. the results show that the luminous tesult is best when concentration ratio of Yb3+/Tm3+is5:1, doping concentration of Tm3+ions is2.0mol%and treatment temperature is700℃. Ultraviolet emission peak, blue and red emission peak are the two-photon process, and the pertinent up-conversion mechnism model of the sample were proposed.