Sonochemical synthesis and characterization of pure nanometer-sized Fe₃O₄ particles

Sonochemical synthesis of pure nanometer-size Fe₃O₄ powder with particle size of ca 10 nm is reported in this article. Fe₃O₄ can be simply synthesized by sonication of iron(II)acetate in water under an argon atmosphere. The properties of pure nanometer-size Fe₃O₄ particles were characterized by X-ray diffraction, Mössbauer spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA) with an external magnetic field, and quantum design SQUID magnetization measurements. The prepared Fe₃O₄ nanoparticles are superparamagnetic and its magnetization at room temperature is very low (<1.25 emu g^-1).