单分散双相可溶四氧化三铁纳米微粒的多醇法制备及磁性

以具有生物相容性的三嵌段共聚物聚氧乙烯-聚氧丙烯-聚氧乙烯为表面活性剂,利用多醇合成法制备了Fe3O4纳米微粒;采用X射线粉末衍射仪、傅立叶变换红外光谱仪及透射电子显微镜分析了Fe3O4纳米微粒的晶体结构、化学结构及显微结构,采用振动样品磁强计测定了其磁性能.结果表明,所制得的Fe3O4磁性纳米微粒结晶度高,在室温下显示近似超顺磁性.采用Langevin方程对Fe3O4纳米微粒的磁滞回线进行拟合,结果显示其为磁性单畴.此外,Fe3O4磁性纳米微粒在无机和有机溶剂中均具有很好的分散性,显示出广阔的应用前景.

Preparation of mono-sized bi-phase dispersible Fe304 nanoparticles and evaluation of their magnetic properties

Fe304nanoparticles were prepared by polyol process with the assistance o{ biocom- patible triblock copolymer, poly （ethyleneglycol）-block-poly （propyleneglycol）-block-poly （ethyleneglycol） as a sur{actant. The crystal structure, chemical structure, and microstructure o{ as-prepared Fe304 nanoparticles were analyzed by X-Ray diffraction, Fourier transform in- {rared spectrometry, and transmission electron microscopy, while their magnetic properties were evaluated with a vibrating sample magnetometer. It was {ound that as-prepared mono- sized nanoparticles exhibit high crystallinity and approximate superparamagnetic behavior at room temperature. The magnetic hysteresis curves o{ the nanoparticles elucidated by the Lan- gevin equation demonstrate that the magnetite nanoparticles exist in magnetic monodomains. Moreover, as-prepared Fe3 O5 nanoparticles can be well dispersed in both organic solvents and in inorganic solvents, showing promising prospect oF application.