[Luminescence characteristics of terbium-doped nanocrystalline zinc oxide].
It is known that zinc oxide is a kind of important functional and novel material of II-VI wide bandgap semiconductor (Eg = 3.37 eV), and has excellent microstructural, chemical and physical properties. The intensity of photoluminescence, luminescence peak positions and other kinds of luminescence properties of ZnO : RE3+ nanocrystalline are strongly dependent on the annealing temperature and time, and the concentration of the doping rare earth ions. Terbium-doped zinc oxide nanocrystalline were successfully prepared by sol-gel process at different annealing temperature. Photoluminescence spectrum (PL), photoluminescence spectrum excitation(PLE) and X-ray diffraction pattern(XRD) of nanocrystalline ZnO : Tb3+ with excitation wavelength 368 nm were measured at room temperature. The emission from 5D4-->7F6 (485 nm), 5D4-->7F5 (544 nm), 5D4-->7F4 (584 nm) and 5D4-->7F3 (620 nm) of Tb3+ ions, and the wide visible band of ZnO were observed. Photoluminescence intensity of nanocrystalline ZnO : Tb3+ on the doping concentration and annealing temperature was given, and it was found that the optimal dopant concentration and annealing temperature were 4 at% and 600 degrees C, respectively. The luminescence process of Tb3+-doped zinc oxide nanocrystalline was investigated by using PL and XRD. The photoluminescence mechanism suggests that there is energy transfer between ZnO nanocrystalline hosts and the doping Tb3+ centers.
Song
Guo-li
GL
Department of Physics, Harbin University, Harbin 150086, China. S.gl@263.net