Luminescence properties of Tm³⁺ /Yb³⁺ ,Er³⁺ /Yb³⁺ and Ho³⁺ /Yb³⁺ activated calcium tungstate

À´Ô´ÆÚ¿¯£ºJOURNAL OF RARE EARTHS2011ÄêµÚ12ÆÚ

ÂÛÎÄ×÷ÕߣºZ.Pisku¯Ûa K.Staninski S.Lis

ÎÄÕÂÒ³Â룺1166 - 1169

Õª    Òª£ºCaWO4 phosphor activated by the Tm3+/Yb3+,Er3+/Yb3+ and Ho3+/Yb3+ ions were synthesized by a traditional high-temperature solid-state method.The crystal structures and morphologies of the products were characterized by X-ray powders diffraction method£¨XRD£© ,infrared spectra£¨FT-IR£© and scanning electron microscopy£¨SEM£© .The samples were found to show up-conversion luminescence properties.CaWO4 doped with Tm3+/Yb3+ showed blue luminescence characteristic of Tm£¨III£© ion in the range of 460-485 nm,corresponding to the 1G4¡ú3H6 electronic transition.CaWO4 doped with Er3+/Yb3+ showed strong green luminescence at 510-565 nm£¨2H11/2,4S3/2¡ú4I15/2£© and weak red luminescence at 640-685 nm£¨4F9/2¡ú4I15/2£© of Er£¨III£© ion.CaWO4 doped with Ho3+/Yb3+ phosphor emitted green luminescence at 525-560 nm£¨5S2,5F4¡ú5I8£© and red luminescence at 630-670 nm£¨5F5¡ú5I8£© and at 730-770 nm£¨5S2,5F4¡ú5I7£© ,which is the characteristic of Ho£¨III£© ion.