Effects of Tb doping on the photoluminescence of Y2O3:Tb nanophosphors

The effects of Tb doping on the photoluminescence (PL) of Y2O3:Tb nanophosphors have been investigated. Nanophosphors were prepared by the glycine-nitrate solution combustion technique using yttria and terbia powders as precursors. PL excitation spectra at room temperature consist of two overlapping bands centered at 277 and 304 nm, whereas emission spectra comprise several groups of lines corresponding to the 5D4→7FJ (J=1-6) 4f electronic transitions of the Tb+3 ions. A direct comparison of nanophosphor and bulk concentration-quenching curves was obtained by annealing the nanophosphor powder and converting it to bulk material without altering the Tb concentration. The peak in the nanophosphor concentration-quenching curve occurs at a concentration ∼3 times higher than that of the bulk.