电化学生长纳米枝状ZnO及其场发射性能研究

Field Emission Characteristics of Dendritic ZnO Nanostructures Prepared by Electrochemical Deposition

采用电化学沉积法在阴离子表面活性剂十二烷基苯磺酸钠(SDBS)的作用下生长纳米枝状氧化锌(ZnO),通过扫描电子显微镜(SEM)、X射线衍射(XRD)和场发射测试,系统研究了不同沉积时间下纳米枝状ZnO的形貌、结构与场发射性能.研究结果表明:由于表面活性剂中阴离子的位阻效应,导致在ZnO主干上电化学生长了多个ZnO的分枝,并且纳米枝状ZnO的场发射性能随着沉积时间的增加出现先升高后降低的趋势.其场发射性能的提高主要取决于ZnO主干上分枝的形貌和密度,在沉积时间为90 min时,每支ZnO的主干上分别生长了约2~10个分枝,获得最佳的纳米枝状ZnO场发射性能,开启场强低至1.54 V/μm,场增强因子高达59 739.

Dendritic ZnO nanostructures were prepared through electrochemical deposition on ITO substrate with the effect of anionic surfactant sodium dodecyl benzene sulfonate （SDBS）. The morphology and structure characteristics of as-prepared ZnO nanostructures at different deposition times, were investigated by scanning electron microscope （SEM） and X-ray diffraction （XRD）, respectively, and their field emission properties were also studied. The results show that ZnO branches were grown on ZnO trunks, under the effect of steric hindrance in suffactant, and the field emission property of the dendritic ZnO nanostructres increased at first and then decreased with the deposition time. The improvement of field emission property mainly depends on the morphology and density of branches on the ZnO trunks. The dendritic ZnO nanostructures achieved the best field emission performance when the deposition time was 90 min, and there were about 2-10 ZnO branches grown on each ZnO trunk. Moreover, the dendritic ZnO nanostructures exhibited a low turn-on field of 1.54 V/μm and a high field enhancement factor of 59 739.