A Raman study of G-bands in isolated and bundled triple-walled carbon nanotubes

The G-band is a Raman-active phonon mode, caused by tangential and longitudinal stretching of the two dissimilar carbon atoms in the unit cell. This mode is well studied in other forms of carbon, e.g. graphite, graphene, single-walled and double-walled carbon nanotubes. Building on that knowledge, a study on bundled and isolated tripled-walled carbon nanotubes (TWNT) is presented. Of particular interest is how many G-band peaks are present, their lineshapes, and how the G-band frequencies of the constituent tubes are affected from being in a TWNT system compared to if they were just SWNTs.