Novel Magnetic Nanoparticles and Nanoflakes

新型磁性纳米颗粒和纳米薄片

• 批准号: 1005871
• 负责人: George Hadjipanayis
• 金额: $ 34.5万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-15 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1005871&HistoricalAwards=false
• 关键词: Novel; Magnetic; Nanoparticles; Nanoflakes

TECHNICAL SUMMARY: The proposed research is focused on the synthesis and characterization of magnetically hard rare earth-transition metal (R-TM) nanoparticles and nanoflakes with a size below 100 nm. The ultimate goal is to use these nanoparticles together with magnetically soft Fe(Co) nanoparticles to develop anisotropic nanocomposite magnets with very high energy products. Nanoparticles /nanoflakes based and the RCo5, R2(Fe,Co)17 and R2Fe14B crystal structures will be synthesized by the novel surfactant-assisted ball milling technique which has been proven to be capable of producing separate and magnetically anisotropic nanoparticles. The proposed experiments will lead to a better understanding of the mechanism(s) of nanoparticle/nanoflake formation that would allow the preparation of larger amounts of nanoparticle/nanoflake powders with uniform and controlled size which are needed for the study of the fundamental and technological properties. The proposed studies on nanoparticles with particle sizes in the range of 4-100 nm, will enable investigations of particle size and surface effects on the crystal structure, the magnetic structure and the fundamental and hard magnetic properties of the particles. The newly developed nanoparticles/nanoflakes with tailored properties will then be assembled together with magnetically soft Fe(Co) nanoparticles via a "bottom-up" approach to form aligned nanostructures which may lead to the development for the first time of highly anisotropic nanocomposite permanent magnets with very high energy products.NON-TECHNICAL SUMMARY: The proposed study is aimed at the fabrication of rare-earth alloy (SmCo5 and Nd2Fe14B) powders with size below a few millionths of an inch, and the study of their magnetic properties as a function of particle size. The rare earth alloy nanopowders with the best properties will then be used together with Fe(Co) nanopowders in a bottom-up approach to develop high performance composite magnets with strength significantly higher than those of the best available Nd-Fe-B magnets. Furthermore, the amount of rare earth in these composite magnets will be lower by 30-40% and this will decrease the future dependency on these scarce rare earths metals. The high performance magnets will lead to lower-cost, more efficient energy and power-dense devices that will result in a substantial reduction in our nation's dependence upon foreign sources of fossil fuels. The project will also provide education and training of students in the important and critical areas of permanent magnets and nanoscale magnetism which are vital to the U.S. economy and defense.

技术概要：拟议的研究重点是磁性硬稀土-过渡金属（R-TM）纳米颗粒和纳米片的合成和表征，尺寸小于100 nm。最终目标是将这些纳米颗粒与软磁Fe（Co）纳米颗粒一起使用，以开发具有非常高的能量积的各向异性纳米复合磁体。基于纳米颗粒/纳米片和RCo 5，R2（Fe，Co）17和R2 Fe 14 B晶体结构将通过新型表面活性剂辅助球磨技术合成，该技术已被证明能够产生单独的和磁各向异性的纳米颗粒。所提出的实验将导致更好地理解纳米颗粒/纳米片形成的机制，这将允许制备更大量的具有均匀和受控尺寸的纳米颗粒/纳米片粉末，这是研究基本和技术性质所需的。对粒径在4-100 nm范围内的纳米颗粒的拟议研究将能够调查粒径和表面对颗粒的晶体结构、磁结构以及基本和硬磁性质的影响。新开发的具有定制特性的纳米颗粒/纳米片然后将通过“自下而上”的方法与软磁Fe（Co）纳米颗粒组装在一起以形成对齐的纳米结构，这可能导致首次开发具有非常高的能量积的高度各向异性的纳米复合永磁体。拟议的研究旨在制造尺寸低于百万分之几英寸的稀土合金（SmCo 5和Nd 2Fe 14 B）粉末，并研究其磁性能随粒度的变化。然后将具有最佳性能的稀土合金纳米粉末与Fe（Co）纳米粉末一起使用，以自下而上的方法开发高性能复合磁体，其强度显著高于最佳可用的Nd-Fe-B磁体。此外，这些复合磁体中的稀土含量将降低30-40%，这将减少未来对这些稀缺稀土金属的依赖。 高性能磁体将导致更低成本，更有效的能源和功率密度的设备，这将导致我们国家对外国化石燃料来源的依赖大幅减少。该项目还将在永磁体和纳米磁性的重要和关键领域为学生提供教育和培训，这些领域对美国经济和国防至关重要。