Thiolation of single-wall carbon nanotubes and their self-assembly

A method for the thiolation of single-wall carbon nanotubes has been developed by exposing a sulfur/carbon nanotubes mixture to an argon/hydrogen gaseous plasma. X-ray photoelectron spectroscopy provides evidence of the existence of sulfur attached to carbon on the carbon nanotubes samples and Raman spectroscopy results show that the carbon nanotubes’ structure has been preserved after the treatment. One added advantage of the reported method is that excess oxygen is not present on the nanotubes. The thiolated carbon nanotubes are shown to self-assemble onto gold electrodes. Our method for thiolating carbon nanotubes provides a reliable and simple way for preparing functionalized tubes for nanoelectronic circuits based on carbon nanotubes.