Temperature effect in the crystallite size and the photoluminescence of nanocrystalline ZrO_2:Sm~(3+) phosphor

摘要

Nanocrystalline ZrO_2:Sm~(3+) doped at 2 mol% was prepared by sol-gel process and the structure and photoluminescence characterization as function of the annealing temperature were performed. Strong visible fluorescence emission produced by transitions ~4G_(5/2) → ~4H_(5/2,7/2,9/2) of Sm~(3+) was obtained by energy transfer process exciting the host at 320 nm and by direct excitation at 408 nm. The experimental results show a quenching of the emission bands by reducing the annealing temperature that is associated with a high content of tetragonal structure. Furthermore, an important change in the structure of the signal emitted was observed when ion was excited directly and the annealing temperature was reduced. These results suggest the possibility to tune the emission of ZrO_2:Sm~(3+) nanophosphor.