Effect of tetrahedral amorphous carbon coating on the resistivity and wear of single walled carbon nanotube network
Single walled carbon nanotube networks (SWCNTNs) were coated by tetrahedral amorphous carbon (ta C) to improve the mechanical wear properties of the composite film. The ta C deposition was performed by using pulsed filtered cathodic vacuum arc method resulting in the generation of C+ ions in the energy range of 40 60 eV which coalesce to form a ta C film. The primary disadvantage of this process is a significant increase in the electrical resistance of the SWCNTN post coating. The increase in the SWCNTN resistance is attributed primarily to the intrinsic stress of the ta C coating which affects the inter bundle junction resistance between the SWCNTN bundles. E beam evaporated carbon was deposited on the SWCNTNs prior to the ta C deposition in order to protect the SWCNTN from the intrinsic stress of the ta C film. The causes of changes in electrical resistance and the effect of evaporated carbon thickness on the changes in electrical resistance and mechanical wear properties have been studied.