Study on the Preparation and Optical Properties of Graphene Oxide@Fe(3)O(4) Two-Dimensional Magnetically Oriented Nanocomposites

In this work, graphene oxide@Fe(3)O(4) (GO@Fe(3)O(4)) two-dimensional magnetically oriented nanocomposites were prepared through the co-precipitation approach using graphene oxide as the carrier and FeCl(3)·6H(2)O and FeSO(4)·7H(2)O as iron sources. The samples were characterized and tested by X-ray diffraction, a transmission electron microscope, Fourier-transform infrared spectroscopy, a vibrating-specimen magnetometer, a polarized optical microscope, an optical microscope, etc. The effects of material ratios and reaction conditions on the coating effects of Fe(3)O(4) on the GO surface were investigated. The stable GO@Fe(3)O(4) sol system was studied and constructed, and the optical properties of the GO@Fe(3)O(4) sol were revealed. The results demonstrated the GO@Fe(3)O(4) two-dimensional nanocomposites uniformly coated with Fe(3)O(4) nanoparticles were successfully prepared. The GO@Fe(3)O(4) two-dimensional nanocomposites exhibited superparamagnetic properties at room temperature, whose coercive force was 0. The stable GO@Fe(3)O(4) sol system could be obtained by maintaining 1 < pH < 1.5. The GO@Fe(3)O(4) sol showed magneto-orientation properties, liquid crystalline properties, and photonic crystal properties under the influence of the external magnetic field. The strength and direction of the magnetic field and the solid content of the GO@ Fe(3)O(4) sol could regulate the aforementioned properties. The results suggest that GO@Fe(3)O(4) two-dimensional magnetically oriented nanocomposites have potential applications in photonic switches, gas barriers, and display devices.