Defect Evolution of Ion-Exposed Single-Wall Carbon Nanotubes

The electronic properties of carbon nanotubes depend on several factors such as diameter, chirality, and defects. Defects such as vacancies can drastically modify the electronic properties of these nanostructures. The introduction of defects by irradiation processes can not only lead to interesting defective nanomaterials but also tailor its intrinsic properties for specific electronic applications. The ability to accurately identify and quantify defects in carbon nanotubes is of major importance for their incorporation into electronic devices. We report on a newly developed quantitative method which combines a known fluence or pulse of ions from a focused beam source with Raman spectroscopy for characterization of defects enabling the detection of systematic variations in defect concentration emerging at 0.5% from different single-wall carbon nanotube (SWCNT) types, semiconducting and metallic. It was also demonstrated that this result is independent from the selected ion species and its energy for thin films, which makes both types of ions suitable for these types of manipulations and characterizations. In this paper, the methods described and exploited can be performed without unique experimental setup or sample preparation and thus enabling in situ accurate characterization of SWCNTs, devices, and other targeted applications.