Effect of Cysteine Substitutions on the Structural and Magnetic Properties of Fe3O4-Cysteine/RGO and Fe3O4/RGO-Cysteine Nanocomposites

We synthesized by electrostatic self-assembly route in basic solution Fe3O4-cysteine/RGO and Fe3O4/RGO-cysteine nanocomposites. In this method, electrostatic interaction was created via negatively charged surface of the reduced graphene oxide and reduced graphene oxide-cysteine sheets and positively charged surface of the Fe3O4 and Fe3O4-Cys nanoparticles in aqueous solution. The structural and magnetic properties of the prepared samples were analyzed by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM), respectively. The dependences of magnetization as a function of applied field using a vibrating sample magnetometer exhibit S-like curves, indicating a magnetic hysteresis behavior for all samples. It clearly showed that, the nanocomposites showed a reduction of saturation magnetization to the Fe3O4 nanoparticles.