Research On Dispersity And Microwave Absorbability Of Carbon Nanotubes With Ni Coating

Carbon nanotubes are potential microwave absorptive materials. Carbon nanotubes have many especial nano characteristics. As a result of the intertwist, the dispersity of carbon nanotubes must be improved firstly. Then, Ni was deposited on the surface of them. They will have both dielectric loss and permeability loss.Firstly, by circumfluence disposal and polyvinyl alcohol oxidations, the dispersity of carbon nanotubes was improved. The top of the carbon nanotubes is opened, and the intertwining carbon nanotubes are cut into short carbon nanotubes. The quantity of the short carbon nanotubes increases with time consuming.Secondly, much functional group were obtained on the surface of carbon nanotubes by acid treatment, and high density activated sites were formed on the surface of carbon nanotubes after activated in Sn and Pd solution subsequently. High densities activated are the key to obtain continuous layer.Thirdly, by electroless plating, Ni was deposited respectively on the surface of carbon nanotubes. And SEM,EDX were employed to analyze plating layer. The dielectric constant,permeability and R～f curve of carbon nanotubes with Ni coating were measured.It is found that Ni coating can be deposited and formed on the surface of carbon nanotubes. The dielectric constant,permeability of carbon nanotubes with coating Ni have peak value from 2GHz to 18GHz. The maximum absorptive attenuation is about -7.4dB.