Effects of annealing on the photoluminescence of Terbium-doped Zinc Oxide Nanocrystalline

摘要

Terbium-doped zinc oxide nanocrystalline are successfully prepared by Sol-Gel process at various annealing temperature from 400°C to 800°C. Photoluminescence spectrum (PL)、 Photoluminescence spectrum excitation(PLE) and X-ray diffraction pattern(XRD) of nanocrystalline ZnO:Tb~(3+) with excitation wavelength 368nm are measured at room temperature. XRD pattern indicates that nanocrystalline ZnO:Tb~(3+) has a hexagonal wurtzite structure and polycrystalline.The mean grain size of nanocrystalline ZnO:Tb~(3+) was 8nm ～ 12nm calculated by Debye-Scherrer formula. Emissionfrom ~5D_4→~7F_6 ( 485nm ) , ~5D_4→~7F_5 ( 544nm ) ,~5D_4→~7F_4 ( 584nm ) and ~5D_4→~7F_3 ( 620nm ) of Tb~(3+) ions, and wide visible band of ZnO were observed. Relationship between Photoluminescence intensity of the peaks of nanocrystalline ZnO:Tb~(3+) and annealing temperature were given, it was found that the optimal dopant concentration and annealing temperature was 4at% and 600°C. The luminescence process of Tb~(3+) -doped zinc oxide nanocrystalline has investigated by using PL, PLE and XRD. Photoluminescence mechanism suggests that there is energy transfer between ZnO nanocrystalline hosts and the doped Tb~(3+) centers.