Air-stable Co-, Fe-, and Fe/Co-nanoparticles and ferrofluids
Air-stable Co-, Fe-, and Fe/Co-nanoparticles and ferrofluids
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DOI：
10.1524/zpch.2006.220.1.3
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发表时间：
2006-01-01
影响因子：
2.5
通讯作者：
Guldbakke, JM
中科院分区：
文献类型：
--
作者：
Behrens, S;Bönnemann, H;Guldbakke, JM
通过在烷基铝存在下热解金属羰基前体并随后进行“平滑氧化”，可以获得空气稳定的 Co、Fe 和 Fe/Co 纳米颗粒。通过透射电子显微镜（TEM、HRTEM）、X射线吸收光谱（XAS）、X射线和紫外光电子能谱（XPS.UPS）、亚稳态冲击电子能谱（MIES）和小角中子散射（SANS）研究了颗粒的结构。纳米粒子与合适的表面活性剂（油酸和月桂酸、二辛基磺基琥珀酸钠（AOT）、LP-4（脂肪酸缩聚物）和KorantinSH（N-油基肌氨酸））的胶溶作用产生分散在载液（例如甲苯）中的磁性流体。煤油、真空油和矿物油，在环境条件下在空气中非常稳定。所得的磁性流体表现出良好的磁性能。提出了几种制备水基 MF 的方法，例如，形成表面活性剂双层、使用相转移剂或用 L-半胱氨酸乙酯进行表面修饰。水基金属磁性流体在许多技术和生物医学应用中具有很高的潜力。研究了钴基铁磁流体在定位系统和磁流体静压轴承领域的技术应用。结果强调了具有金属核心的纳米颗粒铁磁流体的范围。
Air-stable Co, Fe, and Fe/Co nanoparticles are accessible by thermolysis of the metal carbonyl precursors in the presence of aluminium alkyls and subsequent "smooth oxidation". The structure of the particles was investigated by transmission electron microscopy (TEM, HRTEM), X-ray absorption spectroscopy (XAS), X-ray and ultraviolet photoelectron spectroscopy (XPS. UPS), metastable impact electron spectroscopy (MIES), and small-angle neutron scattering (SANS). The peptization of the nanoparticles with suitable surfactants (oleic and lauric acid. sodium dioctylsulfosuccinate (AOT), LP-4 (a fatty acid condensation polymer), and KorantinSH (N-oleyl sarcosine)) yields magnetic fluids dispersed in carrier liquids such as toluene. kerosene, vacuum and mineral oils which are remarkably stable in air under ambient conditions. The resulting magnetic fluids show good magnetic properties. Several methods for the preparation of water-based MF are presented, e.g., formation of surfactant bilayers, using phase transfer agents, or surface modification with L-cysteine ethyl ester. Water-based metallic magnetic fluids have a high potential for a number of technical and biomedical applications. Technical applications of the Co-based ferrofluids in the field of positioning systems and magnetohydrostatic bearings were investigated. The results emphasize the scope of nanoparticulate ferrofluids having a metallic core.