Facile synthesis of stable magnetic fluid using size-controlled Fe_3O_4 nanoparticles

摘要

Magnetic fluids based on superparamagnetic, well-crystalline and mono-dispersed Fe_3O_4 nanoparticles are synthesized by a facile thermal decomposition method. Low-cost Fe(oleate)_3 is used as ferrous resource, and paraffin oil is introduced as solvent and carrier simultaneously. Fe_3O_4 nanoparticles with three kinds of different size (12, 16 and 20 nm), exhibiting different saturation magnetization of 65.51, 68.03 and 74.48 emu/g, respectively, are prepared easily by controlling the thermal decomposition time. Magnetic performance and viscosity-temperature characteristics of the magnetic fluid are also studied. It is found that the saturation magnetization of the magnetic fluid with 5% Fe_3O_4 mass percentage is 2.94 emu/g, which exhibits a good viscosity temperature characteristics compared with paraffin carrier.