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采用水热法制备出菊花状的ZnO纳米线簇,然后利用电泳法将之移植到金属Ti片上,形成均匀的、一定厚度的ZnO纳米薄膜,最后经真空热处理形成ZnO场发射阴极样品。利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对沉积前后的ZnO纳米线簇做了特性鉴定和微结构的表征。对热处理后的阴极样品做了场发射特性测试,发现菊花状纳米ZnO呈现出较低的开启电场2.0 V/μm和较低的阈值电场5.5 V/μm,在场强达到7.5 V/μm时,场发射电流密度为200μA/cm~2,适当地增加涂层厚度可有效提高场发射电流密度及其稳定性,最后探讨了菊花状纳米ZnO的场发射机理。
Chrysanthemum ZnO nanowire clusters were prepared by hydrothermal method and then were transplanted onto the metal Ti film by electrophoresis to form uniform and certain thickness ZnO nanometer films. Finally, ZnO field emission cathode samples were formed by vacuum heat treatment. The characterization and microstructure characterization of ZnO nanowire clusters before and after deposition were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Field emission characteristics of the cathode samples after heat treatment were tested and found that the chrysanthemum nano-ZnO showed a lower on-state electric field of 2.0 V / μm and a lower threshold electric field of 5.5 V / μm, at a field strength of 7.5 V / μm, The field emission current density is 200μA / cm ~ 2. Appropriately increasing the thickness of the coating can effectively increase the field emission current density and its stability. Finally, the field emission mechanism of chrysanthemum nano-ZnO was discussed.