ZnO thin films with different nanostructures are prepared, in which a mixed process involving two main steps is adopted. First, the seed layers are deposited by RF magnetron sputtering, and then, the nano structural films are grown by hydrothermal synthesis on the basis of deposited ZnO seed layers. The crystallographic studies of the ZnO thin films are carried out by X- ray diffraction ( XRD) , which show that only one strong peak of ( 002) wurtzite type phase zinc oxide, no diffraction peaks for impurities are found. The surface morphologies are visualized using scanning electron microscopy (SEM) and reveal that the surface morphologies of the ZnO thin films obtained by different hydrothermal treatments are different: one kind is with nanorods perpendicularly grown on the substrates, and the another is with nanosheets petal ?likely distributed on the substrate surfaces, although the ZnO seed layers are all with continuous and compact structure. The chemical natures of the ZnO thin films are characterized by X- ray photoelectron spectroscopy (XPS) , which indicate that the ratio of O to Zn in lattice of ZnO is close to ? 1? for sputtered seed layers, while for nano?structural ZnO thin films, the concentrations of latticed oxygen are scarce obviously, illustrating many oxygen?related defects exist. Finally, the room?temperature photoluminescence ( PL) measurements of the prepared ZnO thin films are performed. The PL spectra of the nano ?structural films display anomalous characteristics including a broad and strong orange ?red emission band, which can be seen by naked?eyes. Therefore, the mixed method supplies a simple, inexpensive and effective method to fabricate excellent orange red luminescence materials. T he anomalous broad and strong emission band can be attributed to the oxygen vacancy defects.
Wang Yan ** , Zhang Shu Yi , Zhou Feng?Mei , Yang Yue T ao .
Anomalous photoluminescence spectra of nano structural ZnO films prepared by mixed sputtering and hydrothermal methods* [J]. Journal of Nanjing University(Natural Sciences), 2011, 47(2): 218-226
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
{{custom_fnGroup.title_cn}}
脚注
{{custom_fn.content}}
基金
National Natural Science Foundation of China ( 10774074)