Upconversion Emission Studies of Tm3+/Yb3+ Doped MgWO4 for Blue Emitting Devices

Tm3+/Yb3+ codoped MgWO4 phosphor have been synthesized successfully by solid state reaction method. The phase and crystal structure has been analyzed using X-ray diffraction analysis. Upconversion (UC) emission study has been performed upon 980nm laser diode excitation.Yb3+ ions are used as sensitizers in the Tm3+ doped MgWO4 nanophosphors to enhance the luminescence emission intensity of the Tm3+ ions. The observed transitions are P-3(2)-> H-3(6),D-1(2)-> H-3(6),(1)G(4)-> H-3(6),(1)G(4)-> F-3(4), H-3(4)-> H-3(6) corresponding to 254 nm, 363 nm, 480 nm,650 nm and 796 nm wavelengths. The colour emitted by the nanophosphors confirmed with CIE plot. The prepared nanophosphors may be helpful for blue luminescent device fabrications.