Preparation of hydrophobic magnetite by a simple solvothermal method using oleylamine as reducing and surface modification agent

Abstract

Hydrophobic magnetite (Fe3O4) nanoparticles were prepared by a one-step solvothermal processing, in which ferric chloride (FeCl3·6H2O) was used as the iron source. A systematic characterisation of the obtained samples was performed by X-ray diffraction, X-ray photoelectron spectrometry, transmission electron microscope, scanning electron microscope and vibrating sample magnetometer. The experimental results demonstrated that oleylamine not only plays a role as the reducing agent, but also as the surface modification agent. Hydrophobicity of the Fe3O4 nanoparticles therefore, which are covered with oleylamine and long-chain alkanes, is achieved without any surface modification subsequently. With increasing aging time to 9 h, the average particle size of the product obtained is about 80 nm and its saturation magnetisation can reach a higher value, 89 emu/g.