▎ 摘　　要

We describe a novel method for the preparation of a graphene oxide (GPO) -magnetic nanoparticle (Fe3O4) (GPO-Fe3O4) nanostructured hybrids by a simple and effective method. In this method, the fabrication of multi-component nanostructure system involves covalent attachment of GPO with Fe3O4 through dopamine (do) (GPO-do-Fe3O4). Optical microscopy (OM), ultraviolet spectroscopy (UV), Fourier transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were used to demonstrate the successful attachment of Fe3O4 to GPO. It was found that the fabricated nanohybrid shows superparamagnetic behavior and allows rapid separation under an external-magnetic field. The FT-IR analysis of GPO-do-Fe3O4 nanohybrid shows infrared (IR) peaks characteristic of amide (ACOANHA) link on the surface of GPO. TGA analysis clearly shows two major stages of thermal degradation, different from the pattern of observed for dopamine coated Fe3O4 surface. An EDX spectrum of GPO-do-Fe3O4 shows intense peaks for Iron (Fe) along with carbon and oxygen peaks. SEM images further support the FT-IR and TGA results and confirm the presence of Fe3O4 on GPO surface. Thus, the resultant GPO-do-Fe3O4 nanohybrid system carries both electrical and magnetic properties, which are important for applications ranging from electro-magnetic devices to biomedicine. (C) 2013 Elsevier B. V. All rights reserved.