Quantifying carbon-nanotube species with resonance Raman scattering

The method for quantifying the amount of each carbon nanotube specie, as defined by its diameter and chiral angle, as well as the semiconducting-to-metallic ratio in any type of carbon nanotube sample is discussed. Single-wall carbon nanotubes grown by the cobalt-molybdenum catalyst based (CoMoCAT) process are characterized. The semiconducting-to-metallic ratio is found to be 11:1. A single semiconducting specie, named the (6,5) nanotube represents $2∕5$ of the sample, while the most abundant metallic nanotube is the (7,4), which exhibits a diameter similar to the (6,5).