Color-tunable up-conversion emission from Yb3+/Er3+/Tm3+ tri-doped T-AgGd(W,Mo)2O8 phosphors

• AgGd(W,Mo)2O8:Yb3+/Er3+/Tm3+ phosphors show color-tunable blue, green, and red UC emissions.
• The samples’ UC emission color can be switched with the concentrations of doped ions.
• The blue, green and red UC mechanisms are interpreted reasonably as three- and two- photon process.

Tetragonal Yb3+/Er3+/Tm3+ tri-doped AgGd(W,Mo)2O8 phosphors were prepared by the high-temperature solid-state method. When the phosphors were excited at 980 nm, the UC emission of blue at 475 nm, green at 525 and 550 nm, and red at 656 nm were corresponding to the 1G4 → 3H6 transition of Tm3+ ions, the 2H11/2,4S3/2 → 4I15/2 transitions of Er3+ ions, and the 4F9/2 → 4I15/2 transition of Er3+ ions, respectively. The blue UC emissions originate from a three-photon mechanism, while the green and red ones of Er3+ from two-photon process. The UC emission color of the Yb3+/Er3+/Tm3+ tri-doped AgGdW2O8 samples switched from green to white, and then to red depending on the concentrations of Er3+ and Tm3+. After doping with Mo(VI), tetragonal AgGdW2O8 was transformed into tetragonal AgGdMo2O8, resulting in a slightly enhanced UC luminescence intensity with the favor of the red emission of Er3+ ion.

The doping ions tune the UC luminescence of the T- AgGd(W,Mo)2O8:Yb3+/Er3+/Tm3+ material.Figure optionsDownload as PowerPoint slide