One-pot Synthesis of Monodisperse Magnetite in Aqueous Mixed Surfactant Solutions

Monodisperse magnetite (Fe3O4) nanoparticles with particle size of about 10 nm have been prepared by 1,2-dodecanediol reduction of iron acetylacetonate (Fe(acac)(3)) in the presence of oleic acid and oleylamine in dioctylether. The effects of surfactants and reductant on the particles size and morphology were examined. TEM results show that the use of oleic acid and oleylamine suppressed the growth of magnetite nanoparticles and made the particles size reduced from around 24 nm to 10 nm, a variety of particles morphology has arose and schistic hexagonal Fe3O4 nanoparticles were achieved. Magnetic properties show that the as-synthesized Fe3O4 nanoparticles possess features of high saturation magnetization Ms (88 emu/g) and zero remanent magnetization Mr, facilitating their use as magnetic tags for biomedical applications.