权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Hydrothermal Synthesis of Magnetic Single Crystals in Thermally and Chemically Stable Reaction Fields of One-Dimensional Nano Space

一维纳米空间热稳定反应场和化学稳定反应场水热合成磁性单晶

基本信息

批准号：
15310068
负责人：
KYOTANI Takashi
金额：
$ 9.15万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

By chemical vapor deposition of propylene over an anodic aluminum oxide (AAO) film, not only the outer surface but also the inner surface of AAO nanochannels can be fully covered with carbon. The carbon-coated nanochannels can be used as a template in hydrothermal treatment that requires sever alkaline conditions. In the first year we reported our attempt at the synthesis of single crystal nanorods by hydrothermal reaction of nickel compounds in the cavity of the carbon-coated nanochannels and demonstrated that hydrothermal synthesis method can be applied to template-based preparation of nano-sized materials. However, we had some difficulty to insert ferromagnetic metal into the nanochannels using this hydrothermal method. Then we found that ferromagnetic metal (Permalloy) was electrochemically deposited on the carbon-coated nanochannels in the AAO layer in an electroplating bath. Moreover, not only soft magnetic alloy such as Permalloy but also hard magnetic materials such as nickel metal were able to be deposited.In the above electroplating method, Permalloy deposition had never been observed inside the nanotubes, but only on the external surface, when we used the carbon-coated AAO film as a cathode for the electroplating of Permalloy. We then removed only the carbon deposited on the external surface of the AAO film with leaving carbon inside the channels and found metal deposition in the cavity of the nanotubes. This is because electroplating into nano space surrounded by electro-conductive material (carbon) is very difficult. However, for the application of high-density magnetic recoding media, such carbon layer on the external surface should be kept, because the carbon can play a role of a protective and lubricated layer. We thus make every effort to electro-chemically deposit Permalloy in the carbon-coated nanochannels in the AAO and finally have succeeded in such deposition by precisely controlling the electroplating conditions.

通过在阳极氧化铝（AAO）薄膜上化学气相沉积丙烯，不仅AAO纳米通道的外表面而且内表面都可以被碳完全覆盖。碳涂层纳米通道可用作需要严格碱性条件的水热处理的模板。第一年，我们报道了通过镍化合物在碳包覆纳米通道空腔中的水热反应合成单晶纳米棒的尝试，并证明水热合成方法可以应用于基于模板的纳米材料的制备。然而，我们在使用这种水热方法将铁磁金属插入纳米通道中遇到了一些困难。然后我们发现铁磁金属（坡莫合金）在电镀槽中电化学沉积在 AAO 层的碳涂层纳米通道上。此外，不仅可以沉积坡莫合金等软磁合金，还可以沉积镍金属等硬磁材料。在上述电镀方法中，当我们使用碳包覆的AAO薄膜作为坡莫合金电镀的阴极时，在纳米管内部从未观察到坡莫合金沉积，而仅在外表面上观察到坡莫合金沉积。然后，我们仅去除沉积在 AAO 薄膜外表面的碳，将碳留在通道内，并在纳米管的空腔中发现金属沉积。这是因为电镀到被导电材料（碳）包围的纳米空间是非常困难的。然而，对于高密度磁记录介质的应用，应该保留外表面的这种碳层，因为碳可以起到保护层和润滑层的作用。因此，我们尽一切努力在AAO的碳涂层纳米通道中电化学沉积坡莫合金，并最终通过精确控制电镀条件成功实现了这种沉积。