ZnO纳米线的快速生长机理及其场发射性能研究

为了快速制备具有优良场发射性能的ZnO纳米线,对ZnO纳米线的生长机理及场发射性能进行研究。首先采用优化的两步法制备出高长径比的ZnO纳米线,其次采用SEM对ZnO的微观形貌进行表征,然后,在分析形貌特点的基础上,说明了强碱体系下ZnO纳米线薄膜的快速生长机理。最后,对典型样品的场发射性能进行了测试。测试果表明,优化后的两步法,只需3h即可获得直径为40~50nm,长度为2.2~2.7μm,长径比高达54的纳米线。薄膜的开启电场为3.6V/μm,阈值场强为9.1V/um,场增强因子β高达3 391。研究表明,高pH值溶液可以加快ZnO纳米线沿C轴方向的择优生长,获得高长径比的ZnO纳米线,进而获得优良的场发射性能。

Rapid growth mechanism and field emission properties of ZnO nanowires

In order to prepare ZnO nanowires with excellent field emission performance, the growth mechanism and field emission performance were studied. Firstly, the high aspect ratio ZnO nanowires were prepared by the optimized two-step method. Secondly, the morphologies of ZnO were characterized by SEM. Then, based on the analysis of the morphological features, the rapid growth mechanism of the ZnO nanowires film under strong alkali conditions were described. Finally, the field emission performance of a typical sample was tested. The test results show that with the optimized two-step method, nanowires with a diameter of 40~50 nm, a length of 2.2~2.7 μm, and an aspect ratio of up to 54 can be obtained in only 3 h. The turn-on field of the film is 3.6 V/um, the threshold electric field is 9.1 V/μm, and the field enhancement factor β is as high as 3 391. Studies have shown that high pH solution can accelerate the preferential growth of ZnO nanowire along the C-axis direction, obtain high aspect ratio ZnO nanowires, thereby obtaining excellent field emission performance.