碳包覆坡莫合金纳米粒子磁流体制备及表征

Preparation and Characterization of Carbon Encapsulated Permalloy Nanoparticles Magnetic Fluid

用热解(pyrogenation)-退火(anneal)法制备了碳包覆坡莫合金纳米粒子(carbon encapsulated permalloynanoparticles,CEPNPs),选用油酸为表面活性剂,煤油为载液,采用机械球磨法制备出CEPNPs磁流体。用XRD,粒度分析仪和HRTEM分析了CEPNPs的物相组成、粒度分布和微观形貌;用磁天平法测定了CEPNPs磁流体的磁性能;用旋转粘度仪探讨了其流变学性能。结果表明:制备的CEPNPs具有壳/内核包覆结构,平均粒径在75nm左右;以其制备的磁流体外观呈黑色粘稠状,稳定性好,在无磁场条件下磁流体粘度随转子转速的增大而减小,有外磁场时,磁流体粘度随磁场强度增大而增大。

Carbon encapsulated permalloy nanoparticles（CEPNPs） were prepared with a pyrogenation-anneal method. Nanometer magnetic fluid was obtained by mechanical ball milling, using oleic acid as the modifier and kerosene as the carrier liquid. The phase, particle sizes and microstructure of CEPNPs were investigated with XRD, particle size analyzer and HRTEM respectively; The magnetic properties of magnetic fluid were studied with magnetic scale; And the rheological properties of magnetic fluid were studied with rotational viscometer. The results indicate that CEPNPs are core-shell nanostructure, the particles size is 75 nm on an average; CEPNPs magnetic fluid looks black and viscous and stable, and the viscosity of CEPNPs magnetic fluid decreases with increasing shear rate without magnetic field and increases with the applied magnetic field.