| Field electron emission has more tremendous prospect in flat panel displays and other electronic devices. In the past few years, scientists have been looking for suitable materials with low turn-on field, high emission current density and good current stability all the time. Some carbon-based materials such as diamond, diamond-like carbon (DLC) and carbon nanotubes (CNTs) have good field emission properties especially CNTs due to its very low turn-on field and high emission current density. However, the emission current of carbon-based materials were not so stable that this kind of materials were limited in the large scale application. It has been given more attention that the wide band oxide semiconductors especially the fibrous materials with one-dimensional nanostructure. This kind of materials has not only the characteristics of low turn-on field and high emission but also have good chemical stability ensuring the emission current stable and uniform.Zinc oxide (ZnO) is an important II-VI wide bnad oxide semiconductor, with good thermal and chemical stability, which has potential applications in short-wave opto-electronic devices and field emission displays. ZnO materials with one-dimensional nanostructure have a lot of special properties especially excellent field emission property. Investigation on fabrication, properties, growth mechanisms and applications of ZnO one-dimensional nanostructures plays an important role in both fundamental research and practical applications.In the thesis, ZnO one-dimensional nanofibres were prepared by electrospinning and field emission properties were researched. The main content was summarized as follows:1. ZnO nanofibres were fabricated by sol-gel process and electrospinning technique, using polyvinyl alcohol (PVA Mw=89,000～98,000) and Znic acetate as precursor. Kinds of factors which affected the morphology, size, structure and uniformity of fibres were discussed systematically, showing that the mass of znic acetate, the concentration of PVA, the weight of solvent and annealing temperature were the major factors affecting the characteristics.2. The products were characterized by scanning electron microscope (SEM), x-ray diffraction (XRD), raman spectrum (Raman) and field emission (FE). The results show that pure single component of ZnO nanofibres with homogeneous diameters of 50-200nm or nanostructures were obtained after calcination of various concentration ratio of PVA/Zn(CH3COO)2·H2O hybrid fibres and all the products were wurtzite phase.3. The test result of field emission properties of different ZnO products show that the turn-on field of nanofibres was between 5.1V/μm and 12.3V/μm with the maximum emission current density above 3000μA/cm2 while the emission current density of the uneven morphology was lower and unstable at high electric field. Results indicated that the field emission properties of ZnO one-dimensional nanofibres with smaller diameters were so good that this kind of ZnO nanomaterials may have wide applications in plan field emission display.
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