Fe3O4 Nanocrystals with Novel Fractal

Abstract

Fe₃O₄ novel fractal nanocrystals have been synthesized by a surfactant-assisted solvothermal process for the first time. X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), Mössbauer spectroscopy (MS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) have been used to investigate the novel fractal nanocrystals. The lengths of the fractals are about 2−3 μm, and the trunks and branches of Fe₃O₄ fractals have almost the same diameters of ca. 30−50 nm. The roles of surfactant PEG-20000 and N₂H₄ have been discussed in detail. One key fact has been found that the ferrocene concentration has a vital effect on the morphologies of the products. The side-branching process and the oscillation of the concentration have been proposed to illustrate the formation mechanisms of the fractal nanocrystals. In addition, magnetic properties of Fe₃O₄ fractal nanocrystals have also been detected by a vibrating sample magnetometer, showing relatively high saturation magnetization (M s) of ca. 78.75 emu/g.