磁性金属纳米结构的制备及动态磁性能研究

【作者】 陈文兵；

【导师】 韩满贵；

【作者基本信息】 电子科技大学 ， 材料科学与工程， 2010， 硕士

【摘要】 由于磁性金属纳米材料有很多独特的性质,以及其在诸多领域的广泛应用前景,磁性金属纳米材料成为近年来的一大研究热点。本文从微磁学模拟和实验两个方面,对多种金属纳米结构如纳米线、纳米管和纳米点的动态磁性能做了研究。首先本文从OOMMF微磁学模拟的角度出发,研究了单根纳米线,纳米管和纳米点的动态磁化率。模拟结果显示,这些纳米结构的动态磁谱随着各种参数如直径、长度、饱和磁化强度,磁晶各向异性常数的变化而变化。另外,对纳米线阵列和纳米点阵的动态磁谱的研究表明静磁耦合作用的影响不可忽略。在此基础上,我们对纳米线进行了各种组合并模拟了其磁谱。我们利用电化学方法在氧化铝模板中制备了各种磁性纳米线,包括Co纳米线, Ni纳米线, Ni/Co多层纳米线和CoNiCu合金纳米,对其形貌、晶体结构、静磁性能、动态电磁性能做了表征和讨论。总的来讲,所制备的各种磁性纳米线的磁滞回线都显示出了较弱的各向异性。实验结果还表明,磁性纳米线可以作为质量轻,吸收强的高频微波吸收材料,有望应用于GHz频段。然后,我们利用无电化学沉积法制备了磁性NiP纳米管,利用电化学沉积在氧化铝模板和聚碳酸酯模板中制备了CoNiCu/Cu多层纳米管。和纳米线相比,磁性纳米管具有很多不同的特征,比如其吸波性能出现了多峰和宽频带吸收的特点。更多还原

【Abstract】 Due to their unique properties and promising applications, magnetic metal nanostructures have attracted a lot of research interests in recent years. Based on micromagnetics and experiments, this work intends to investigate the dynamic properties of various metal nanostructures such as nanowire, nanotube and nanodot.To begin with, the dynamic magnetic spectra of single isolated nanowire, nanotube and nanodot are studied by means of OOMMF. Simulation results indicate that their magnetic spectra are a function of parameters such as diameter, length, saturation magnetization and magnetocrystalline anisotropy constant. In addition, it is revealed that magnetostatic interaction plays an important role in the dynamic properties of nanowire and nanodot arrays. Furthermore, nanowires with different aspect ratio or different saturation magnetization are combined for micromagnetic simulation.Then, various nanowires including Co, Ni, Ni/Co multilayered and CoNiCu alloy nanowires have been prepared within anodized alumina template by electrodeposition, and their morphology, crystal structure, static and dynamic magnetic properties are discussed. The hysterisis loops of all the nanowire arrays manifest little anisotropy. Nevertheless, experimental results suggest these magnetic nanowires as potential microwave absorbers in the GHz range, with light weight and strong absorption.Furthermore, NiP nanotubes were fabricated through electroless chemical deposition and CoNiCu/Cu multilayered nanotube were synthesized within alumina and polycarbonate template through electrodeposition. In comparison with nanowires, nanotubes show many different properties, such as multiple absorbing peaks and wide band absorption peaks in their reflection loss spectra.更多还原