The Ni nanowire arrays (NWAs) with different aspect ratios were prepared in anodized aluminum oxide (AAO) template nanopores by electrodeposition. The results of SEM and TEM demonstrate that the vertically aligned, free-standing Ni NWAs are uniformly distributed on the gold substrate, and the diameter of the nanowires is basically consistent with the pore size of the template. The crystal form is a face centered cubic structure. The smaller the diameter is, the higher the (200) peak intensity is. The field emission performance tests indicate that the Ni NWAs have excellent field emission properties, and the field enhancement factor (β) increases with the aspect ratio rising. The nanowire arrays with a diameter of 80 nm and a length of 15 μm have the best field emission performance. Its β reaches 3686 and the turn-on field is 1.69 V•μm^-1. Nevertheless, the collapse of nanowire structures which makes the Ni NWAs lose its practical value when the length greater than 15 μm.

中文翻译：

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不同长径比Ni纳米线阵列的制备及场发射特性


通过电沉积在阳极氧化铝 （AAO） 模板纳米孔中制备了具有不同纵横比的 Ni 纳米线阵列 （NWA）。SEM 和 TEM 结果表明，垂直排列的独立式 Ni NWA 均匀分布在金衬底上，纳米线的直径与模板的孔径基本一致。晶型为面心立方结构。直径越小，峰强度 （200） 越高。场发射性能测试表明，Ni NWAs具有优异的场发射性能，并且场增强因子（β）随着纵横比的增加而增加。直径为 80 nm、长度为 15 μm 的纳米线阵列具有最佳的场发射性能。其β达到 3686，导通场为 1.69V•^μm-1。然而，当长度大于 15 μm 时，使 Ni NWA 的纳米线结构崩溃失去了其实用价值。