Spectroscopic investigations in Tm3+/Yb3+ codoped Y2O3 phosphor

The Y2O3 phosphors codoped with various concentrations of Yb3+/Tm3+ ions have been successfully synthesized via solution combustion root using urea as fuel. On 980 nm diode laser excitation, the UC emission of synthesized phosphor exhibits the strong emission at rare earth concentration of 0.1 mol% Tm3+ and 2 mol% Yb3+ in Y2O3 lattice. The UC spectra shows intense blue (∼ 476 nm &∼488 nm) and red (∼ 656nm) emission bands which are assigned to 1G4(a) → 3H6, 1G4(b) → 3H6 and 1G4(b) →3F4 transitions of Tm3+ ions respectively. The mechanism involved in UC emission process have been analysed with the help of energy level diagram and pump power study. Moreover, the optical band gap of the optimized sample has been found to be 5.11 eV from diffuse reflectance spectrum. The CIE coordinates of prepared phosphors lies in blue region which unfolds that the prepared phosphors have suitable application in fabrication of blue light display devices.