Luminescence Properties Of Of Nanosized ZrO₂: RE～(3+)

In the thesis, the optical properties of nanosized zirconia powders doped with rare earth were studied at room-temperature. Some important conclusions obtained in our investigations were as follows:Nanosized zirconia powders doped with rare earth (RE) were successfully prepared using co-precipitation method. The main up-conversion emission of the samples doped with low concentrations of Er3+ (no more than lmol%) was green light. In the investigations of the nanosized zirconia powders co-doped with Yb3+ -0.2(0.4,1) mol%Tm3+ ions under 980nm LD excitation, the blue up-conversion emission at 474nm comes from the 1G4-3H6 transition. And, no up-conversion emission was observed in the sample with lmol% Tm3+ ions. The blue up-conversion emission increased gradually with increasing of annealing temperature and pump power. A three-phonon process was ascertained for the blue up-conversion emission by modeling the relation between up-conversion emission intensity and pump power. The luminescence of nanosized zirconia powders doped with Eu3+ ions was investigated under 394nm excitation, the emission of 5D0 7F2 transition peaked at 604nm. Furthermore, an enhanced up-conversion emission at 604nm induced by ultraviolet irradiation was observed for the nanosized zirconia powders doped with Eu3+ ions. The relation between the enhanced fluorescence and the annealing temperature was investigated, and we found that the fluorescence increment decreased with increasing of the annealing temperature.