The Research Of Carbon Nanofibers Catalyzed By Metal Nanoparticles

In this paper,metal catalysts were prepared by direct current sputtering method,solvothermal method,and arc-plasma charge and so on.Using these particles as catalysts,carbon nanofibers?CNFs?were successfully synthesized.The paper focuses on the following areas:1.Copper nanoparticles?CNPs?on silicon substrate were prepared by direct current sputtering and solvothermal method.CNFs were synthesized by chemical vapor deposition?CVD?.The simple current sputtering and solvothermal method were used to synthesize CNPs.The products were characterized by scanning electron microscopy?SEM?,transmission electron microscopy?TEM?,X-ray diffraction?XRD?,atomic force microscopy?AFM?,and high resolution transmission electron microscopy?HRTEM?,the results show that the morphologies and components of the products were influenced by reaction methods,reaction time and copper source.CNPs on silicon substrate prepared by sputtering method were pure and uniform,the thickness of copper can be controlled by the sputtering time;Crystalline spheres prepared by solvothermal method using ethylene glycol?EG?,CuSO₄�5H₂O,N₂H₄�H₂O,and NaOH.CNPs with different morphologies were synthesized by changing the copper source.Vertically aligned CNFs were prepared by CVD using CNPs on the silicon substrate by sputtering method;but the helical CNFs were prepared by CVD using CNPs on the silicon substrate by solvothermal method;the same silicon substrate,the same CNPs,the same condition,the different CNFs,which were caused by the different uniform CNPs on the silicon substrate.2.CNFs catalyzed by copper nickel nanoparticles?CNNs?CNNs were successfully prepared by arc-plasma charge,and CNFs were prepared in tubular furnace using CNNs as catalyst and acetylene as carbon source.The products were characterized by SEM,TEM,XRD,and HRTEM,the results show that CNNs are chain-like spheres and 50nm in diameter,CNFs with symmetric helix growth and liner growth were obtained.It is symmetric between two fibers with a catalyst particle at the node.As the catalyst shapes change,sphere or ellipsoid,the angles between two fibers keep a relative constant of 90�.3.CNFs catalyzed by cuprous oxide nanoparticles?CONs?and cuprous oxide films?COFs?CONs were synthesized by wet-chemical route.The morphology of CONs are different,there are irregular octahedral nanoparticles in the absence of PEG and whiskers-like nanoparticles without PEG.These particles were used as catalysts for the growth of CNFs in a tubular furnace.It is found that CNFs are branched,carbon grow along the cuprous oxide octagonal?111?;COFs are prepared by a simple reduction method,the products were uniform spheres with the diameter of 200 nm.Using these particles as catalysts,CNFs with linear growth were obtained.