| Summary: | 碩士 === 國立成功大學 === 奈米科技暨微系統工程研究所 === 96 === This paper reports a simple method for large-scale fabrication of ZnO nanowires by combining a sol-gel process and an electrospinning process. Gel containing polyvinyl acetate (PVA) and zinc acetate was first prepared as the precursor. The precursor was then electrospun to nanowires. The polymeric nanowires thus obtained were calcined to form ZnO nanowires. By varying the precursor gel properties, the electrospinning conditions (injection rate and spray distance), calcination temperature, and calcination time, the ZnO nanowires having desired characteristics were obtained. The nanowires were characterized using thermogravimetry analysis for the thermo properties, scanning electron microscopy for the morphology, X-ray diffractometry (XRD) and cathode luminescence spectrometry for the luminescence property. The XRD results show that crystal structure of zinc oxide nanowires largely depends on the calcination temperature and time. The SEM analysis reveals that the zinc oxide nanowires have diameters in the range of 90-500nm. The diameter of the zinc oxide nanowires decreases with increasing zinc acetate concentration, and also decreases as the calcination temperature and time increase. The CL results show that the ZnO nanowires obtained exhibit very weak visible band emission and very strong UV band emission at 368 nm, indicating a good structure quality. This electrospinning technique allows the direct placement of ZnO nanowires during their synthesis to bridge the sensor electrodes. Ethanol-sensing characteristics were also studied.
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