Research On Preparation And Characteristics Of One-dimensional Doped ZnO Mirco/Nanostructures

In this paper, Co, Sn, Na-doped ZnO micro/nanostructures have been synthesized by the carbothermal reduction reaction. The optical and electric properties of the samples have been investigated.The main results are as follows:1. Co-doped ZnO micro/nanostructures:the PL spectra of Co-doped ZnO micro/nanorods in the ultraviolet region show a blue shift, and the peak located at382nm, this means that the Co dopant can change the luminescence properties of ZnO. The grain boundary resistance of an individual Co-doped ZnO micro/nanorod is much greater than its grain resistance. It has very good ohmic contact with the silver paste electrode. We investigate a spectral photoresponse of individual Co-doped ZnO micro/nanorods at different wavelengths. We find that it has response to both UV light and visible light, the highest sensitivity is observed at the wavelength of360nm.It is noted that a photoconductivity response of the individual Co-doped ZnO micro/nanorod measured for light-on and-off states is fully repeatable and periodic.2. ZnO/Zn2SnO4complex oxides micro/nanostructures:With an increase in intensity of the excitation light, the UV light emission intensity firstly decreases and then increases. Almost there is no PL peak in visible light region under other excitation intensity, in addition to the excitation intensity of0.1I0. An individual ZnO/Zn2SnO4micro/nanorod whose grain boundary resistance is up to megohm level has very good Ohmic contact with the electrode. The spectral responsivity curve of the sample shows that it can response in the wide area of the wave length, the peaks are observed at the wavelength of332nm,376nm and767nm.3. Na-doped ZnO micro/nanostructures:The as-synthesized Na-doped ZnO samples exhibited strong UV emission with a major peak at377nm, the UV light emission intensity increases with increase in intensity of the excitation light, but the visible light emission intensity is just opposite. The contact between an individual Na-doped ZnO micro/nanorod and electrode change to schottky contact. Na-doped ZnO has higher responsivity and stability than the Co-doped ZnO micro/nanorods, Na-doped ZnO micro/nanorod is proper to be more suitable for ultraviolet photodetector.