Résumé
The separation of carbon nanotubes (CNT) into samples that are monodisperse in diameterand chirality still constitutes a bottleneck for specific applications of this material. According topreliminary experimental results [1], surfactant-assisted separation of CNT is a promisingsolution of this problem. However, the mechanism for which surfactants help the separationwith some specificity, or which surfactants or environmental conditions improve the separationare not yet understood. In this work, we present a multi-ensemble molecular dynamics study ofthe adsorption of sodium dodecyl sulphate (SDS) on a variety of single walled CNT’s [(m, n) =(6,6), (10,2), (11,0), etc.] in aqueous solution at various temperatures. The adsorption of thedodecyl sulfate anions on the CNT is characterized by their atomic radial distribution withrespect to the CNT, distribution of characteristic lengths (radius of gyration), and end-to-endazimuthal angle (which shows the degree of wrapping of the molecule around the CNT). Wediscuss how these are related to the physical characteristics of the CNT’s in solution.