CNT Film Chemically Bonding to Metal Surfaces

Carbon nanotubes can be considered as a chemically stable material with exceptional electrical and thermal conductive properties. Electrically conductive applications of carbon nanotubes (CNTs) have been limited by several factors, among them a lack of robust connections to metal surfaces is significant affecting for CNT widespread applications. In this work CNT side walls bonded to different metal surfaces including Cu, Al, Stainless steel, Au and ITO with electrically conductive aminophenyl linkers which can react with metal substrates via diazonium grafting reaction leaving basic functional groups on the metal surface to react with acidic functional groups of the oxidized CNTs. The chemical nature and robustness of the linker-metal bonding was investigated using X-ray photoelectron spectroscopy and Infrared spectroscopy following ultrasonication. Thin layer of CNTs were observed on the surface of the metal surfaces with scanning electron microscopy analysis after ultrasonication. CNT modified metal surfaces showed enhanced current densities compared to the bare metal surfaces in electrochemical analysis in Ru 2+ /Ru 3+ aqueous solution. Finally, ability of the metal-linker-CNT bonding to enhanced the metal-CNT interface conductivity was demonstrated by measuring interface resistance of the CNT-linker-Au system compared to the direct CNT-metal contacts.