Study On Carbon Nanomaterials And Their Magnetic Functionalized Assembly

Carbon nanomaterials are defined by a kind of carbon material with one dimension less than 100nm in the three-dimensional space at least. They mainly include fullerene, carbon nanotube, graphene, etc. Carbon nanotube and graphene are two shining star since the discovery of fullerene in the field of nanomaterials research. They have excellent electrical properties, field emission properties, thermal conductivity properties, superconducting properties, and hydrogen storage properties. In addition, carbon nanotube with one-dimension structure and the graphene with two-dimensional structure are the best assembled template. So the composites based on these materials have their own unique properties. Thus, they will become the main component of composites with a wide range of value in commercial development in future. Due to the disadvantage of carbon nanotube and graphene in magnetism, we regard them as templates, the inorganic magnetic nanoparticles are assembled on their surface to get the electromagnetic materials. These materials can be applied in the area of electronic nanodevice, magnetic recording material, absorbing material, the sensor and so on.In this paper, a magnetic multi-walled carbon nanotubes-based (MWCNTs-based) composite, MWCNTs/Ni0.5Zn0.5Fe2O4, was synthesized via a facile solvothermal approach. The composites were characterized by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and vibrating sample magnetometry (VSM). The results confirmed that MWCNTs and Ni0.5Zn0.5Fe2O4 coexisted in the composites. The TEM and HRTEM results showed a thick layer of Ni0.5Zn0.5Fe2O4 was intimately connected to the surface of MWCNTs. Furthermore, the probable synthesis mechanism of the magnetic composites was also investigated based on the experimental results. Results indicated that the composites displayed zero coercivity, with no remanence as would be expected for superaramagnetic behavior. The saturation magnetization value of MWCNTs/Ni0.5Zn0.5Fe204 was 45.8emu/g. What is more, this composite was a kind of soft magnetic material.The discovery of graphene and its excellent performance enabled us to extend the research on the assembly of carbon nano-materials. Relevant research based on carbon nanotubes provided a good reference value to study graphene. Synthesis method research had developed at a truly relentless pace. Herein, two different methods were used to prepare it and the products were characterized by XRD, Raman spectroscopy (Raman), infrared spectroscopy (FTIR), atomic force scanning probe (AFM) and TEM. Furthermore, we also explored the formation mechanism of the two methods. The results showed that two methods had their own advantages and disadvantages.A magnetic nanocomposite of graphene sheets-iron oxide (GRs-Fe3O4) was fabricated by a chemical precipitation method, in which sodium dodecyl sulfate (SDS) was used as surfactant to functionalize GRs. In this work, Fe3O4 nanoparticles were loaded on the surface of GRs and the well-assembled composite remained magnetic property of individual Fe3O4 nanoparticles. Moreover, due to the intrinsic peroxidase-like activity of Fe3O4 and the excellent electrochemical property of GRs, the composite exhibited higher electrochemical activity toward the redox process of hydrogen peroxide. The preliminary study on the electrocatalytic activity of GRs-Fe3O4 composite used as electrochemical sensing was carried out.