Synthesis of Monodispersed Magnetite Particles From Different Organometallic Precursors

Magnetite (Fe₃O₄) nanoparticles with very narrow particle size distribution can be obtained by decomposition of an organometallic compound in the presence of oleic acid. It has been shown that the carboxylic acid catalyzes the reaction leading to decreased decomposition temperatures and, consequently, as the surfactant concentration increases, smaller particles are formed. Precursors such as Fe(CO)₅, iron acetylacetonate, and iron-oleate complexes, previously formed from an iron salt, have been used for the preparation of magnetite particles. Although the particles are magnetite in all cases, the size, shape, and distribution of nanoparticles differ depending on the precursor and consequently the samples show different magnetic behavior. Besides, a different mechanism of formation of the nanoparticles is expected and related to the decomposition rate of the precursor