一维Ni/Nd皮芯结构磁性纳米阵列的制备及Ni纳米管生长机制研究

Fabrication and Growth Mechanism of One-Dimensional Ni/Nd Core/Shell Magnetic Nanoarrays

采用直流电沉积的方法,在多孔氧化铝(AAO)模板中沉积得到了高度有序的Ni纳米管/线以及Ni/Nd皮芯结构磁性纳米阵列。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和能谱分析(EDX)对得到的样品进行了结构、形貌以及成分方面的表征。SEM测试表明,所得Ni和Ni/Nd的一维纳米阵列排列规整,直径与AAO孔径相当,且Ni/Nd合金形成了明显的皮芯结构。从Ni/Nd合金的截面还可以看到明显的六方结构,这与Nd的六方晶胞结构一致。另外,相同沉积Ni时间的Ni/Nd合金和Ni纳米阵列的形貌变化证明了Nd的存在,也就是稀土Nd成功沉积的结果。而电子能谱结果也同时证实了稀土Nd的存在。TEM的测试结果初步表征了纳米Ni的管状结构以及皮芯结构的形成过程。结合Ni和Ni/Nd的生长过程对一维纳米阵列的生长机制进行了初步的探讨,并认为一维纳米阵列的生长受多种因素的共同影响,最终形成的纳米结构取决于3个方向的竞争速率结果,并提出了3方向竞争机制。

High ordered one-dimensional Ni nanotubes/nanowires and Ni/Nd core/shell nanoarrays were fabricated by DC electro- chemical deposition into Anodic Aluminum Oxide（AAO）. The test of SEM, TEM and EDX gave the characterization of its structure, performance and composition. SEM patterns showed its high order and the same diameter as AAO. Meanwhile, the Ni/Nd alloy had the obvious core/shell structure. The hexagonal structure was also observed at the top of the nanowires, which was in accordance with the hexagonal crystal structure of Nd. In addition, Ni nanoarrays and the Ni/Nd were compared with the same Ni deposition-time. Its performance change proved the existence of Nd, which was the result of successful deposition of Nd. At the same time, the EDS also gave a definite existence of rare-earth Nd. The test of TEM showed the Ni nanotubes and the formation of Ni/Nd core/shell structure initially. As for the growing situation of Ni and Ni/Nd, a possible growth mechanism of one-dimensional nanoarrays was discussed briefly. What should be believed was that the growth of one-dimensional nanoarrays was determined by the combined effects of many factors. Its growing had three speed directions which decided the final nanostructure. A simple three direction competition mechanism was put forward.