Comparison of the Fe and Pt Nanoparticles with FePt Alloy Prepared by Polyol Process: Shape and Composition Study

In this study, Fe and Pt nanoparticles are first synthesized by decomposition of iron(II) chloride tetrahydrate and reduction of platinum(II) acetylacetonate. Then, FePt nanoparticles are similarly fabricated by adding LiBEt3H to the phenyl ether solution in the presence of oleic acid, oleylamine surfactant at 100°C, followed by refluxing at 255°C. The samples were characterized by transmission electron microscopy and energy dispersive spectroscopy analyses after heat treatments. Transmission electron microscopy images show that self-assembled 8 nm Fe nanoparticles are formed as polygon shape, whereas Pt nanoparticles have broad size distribution. On the other hand, 4.5 nm FePt nanoparticles have standard division about 9%. The results of energy dispersive spectroscopy analysis reveal that the composition of Pt, Fe and FePt nanoparticles gives $Fe_{56}Pt_{44}$ stoichiometry.