Fe_3O_4纳米颗粒的溶剂热法制备及电磁特性研究

Polyol-based synthesis of Fe_3O_4 nanoparticles and their microwave absorption properties

采用溶剂热方法分别在聚乙二醇、三乙二醇溶液中热分解乙酰丙酮铁,得到分散性能良好、尺寸均匀、形貌一致的Fe3O4纳米颗粒,颗粒尺寸为7～8nm。通过X射线衍射及透射电镜研究发现,两种溶液中制备样品均为面心立方结构,且在三乙二醇溶液中制备颗粒分散性更好。分别对两种样品进行磁测量,发现室温时均表现出超顺磁性,398kA/m时的磁化强度分别为50、40A·m2/kg。微波吸收测试显示,颗粒的分散性有利于改善样品的反射损耗。

Fe3O4 nanoparticles were prepared by thermolysis of iron（Ⅲ） acetylacetonate in two different liquid polyols： poly（ethylene glycol） and tri（ethylene glycol）.The nanoparticles are well dispersed,with the shape of approximately spherical and the average diameter of 7-8nm.The results of X-ray diffraction and Transmission electron microscopy show that the particles have face-centered cubic structures and the stability of the aqueous suspension of Fe3O4 nanoparticles prepared in medium TEG is better than those prepared in PEG.Hysteresis loops of both samples show the superparamagnetic feature at room temperature,and give the magnetizations of 50 and 40A·m2/kg,respectively when external magnetic field reach 398kA/m.The microwave absorption measurement exhibited that the better dispersion of Fe3O4 nanoparticles can improve the reflection losses of samples.