Sorting of single‐walled carbon nanotubes by amphiphiles molecules adsorption studied by resonant Raman excitation profile

Abstract

Adsorption of specifically designed polyaromatic amphiphiles were used to sort HiPCo single-walled carbon nanotubes (SWNTs) with different helicities. The sorting is investigated by resonant Raman excitation profiles. Chiral indexes (n and m) of SWNTs present in our samples are determined by fitting the Raman peaks observed in the radial breathing modes region (RBM). Scanning over an excitation energy range between 2 and 2.2 eV with a 0.01 eV step allows to investigate mainly two families of metallic nanotubes (2n þ m ¼ 24 and 2n þ m ¼ 27). The transition energies of nanotubes measured from the Raman spectra differ from the calculated ones, leading to useful corrections of the Kataura plot. The results also display significant differences between the sorted and the reference samples, meaning that discrimination between SWNTs of different properties is possible.