The George Washington University,
Keywords: graphene, magnetic nanoparticles, biological applications
Summary:Nowadays, mass production of high quality Graphene Platelet Networks (GPNs) and Magnetic Nanoparticles (MNs) are highly requested due to their wide range of applications such as flexible electronics, high-frequency transistors, energy storage, and biomedical applications. Due to this request, many synthesis methods have been developed, such as Chemical Vapor Deposition (CVD), Epitaxial Growth and Free-standing Flakes Microwave Synthesis. These methods however, have difficult techniques and require complicated synthesis procedures. They yield low production rates and also have higher manufacturing prices. Recently, a more efficient and environmental friendly method to synthesize GPNs and size controllable MNs has been achieved by our lab with Arc Discharge Plasma and we believe this method can fulfill the demand from the industrial markets all over the world. Proposed here is a single-step direct approach to synthesize GPNs on a heated substrate made by different materials. ( Si, Ni, Mo, Cu, etc. ) The substrate materials could be anything that is able to resist 800C°. The substrate could be processed into different shapes afterwards because the GPNs are well attached to the substrate surface. The whole synthesis procedure only takes a maximum of 5 seconds. We also present here a single-step synthesis and purification of carbon encapsulated MNs in a magnetic field. This method successfully separates MNs and carbon impurities during the synthesis procedure. We also have proved that the size of the MNs decrease with the increase of the magnetic field. This indicates that we could control the size of the MNs by altering the strength of the magnetic field. 200mg pure MNs with different composition ( Fe, Ni, Fe and Ni ) could be produced within 2 mins. Both GPNs and MNs were synthesized using arc discharge plasma, and we achieved high volume production rates and high quality in a relatively short time. The samples were then evaluated using following nano-characterization tools: Scanning Electron Microscopy (Carl Zeiss Sigma VP Field Emission and FEI LV FEG SEM “Teneo”), Raman Spectroscopy (Horiba LabRAM HR), Atomic Force Microscopy (Asylum MFP-3D), Transmission Electron Microscopy ( FEI “Talos” ) and XPS. All the supporting information including synthesis and characterization procedure could be find in the attached PDF file. Some initial biological tests have been done to grow nerve cells on the GPNs substrate and we also check the cell toxicity for the MNs. Both tests on GPNs and MNs yield a potential for biological usage of these materials such as promoting the neurons to grow, targeting drug delivery and possible cancer treatment with the enhancement of Cold atmospheric plasma (CAP). Acknowledgement: This work was supported the U.S. Department of Energy, Office of Science, Basic Energy Science, Materials Sciences and Engineering Division.