Synthesis of Fe-Co alloy particles by modified polyol process

The successful synthesis of Fe-Co nanoparticles by using a modified polyol process is reported. The formation of the alloy nanoparticles was confirmed by X-ray diffraction and X-ray extended absorption fine structure analyses. The concentration of iron in these particles could be varied between 40% and 90% by controlling the reaction conditions such as initial Fe/Co ratio, reaction temperature and hydroxyl ion concentration. The shape of the particles changed from spherical to cubic when the concentration of Fe was increased from 40 to above 60 at. %. The highest magnetization of 225 emu/g was recorded for Fe70Co30 nanoparticles. The magnetization of these particles decreased by about 20% when exposed to severe oxidizing atmosphere for seven days.