纳米稀土铁氧体磁性颗粒的制备研究

Study on Preparation of Rare Earth Ferrite Magnetic Nanoparticles

采用湿化学方法研究制备纳米稀土铁氧体磁性颗粒,研究纳米稀土铁氧体颗粒制备过程中主要影响因素,如pH和RE3+等对纳米稀土铁氧体颗粒粒径及磁性能的影响;同时对纳米Dy铁氧体颗粒的形貌、粒度分布、晶型结构及磁性能进行了分析和研究。研究发现轻稀土对Fe3O4颗粒的磁性有削弱作用,不宜掺杂;重稀土元素掺杂是提高铁氧体磁性颗粒磁性能的有效途径,改善磁性能的强弱顺序为Dy3+>Gd3+>Er3+。制备的Dy铁氧体颗粒的平均粒径为9.6 nm,比饱和磁化强度98.27 A.m2.kg-1,具有超顺磁特性。同时讨论了Dy3+在Fe3O4的晶体结构中取代Fe离子增强磁性能的可能形式。

Rare earth ferrite magnetic nanoparticles were prepared by wet chemical method. The main influencing factors in the preparation process of rare earth ferrite nanoparticles, such as the effect of pH value and RE^3＋ on the rare earth ferrite nanoparticle size and magnetism properties, were discussed in detail. The particles morphology, distribution, crystal structure, and magnetic property of nano Dy ferrite were also investigated. The possible mate for of Dy^3＋ replacing Fe ion in Fe3O4 crystal structure was also discussed. It was found that the light rare earths had decrement effect on the magnetic property of Fe3O4 particles. But doping heavy rare earths was an effective approach to enhance the magnetic property of ferrite particles, and its effect ability on magnetic properties is in an order as Dy^3＋ 〉 Gd^3＋〉 Er^3＋. The average size of Dy-ferrite particles with superparamagnetic property was about 9.6 nm, and the saturation magnetization intensity was about 98.27 A· m^2·kg^-1.