Carbon nanotubes dressed by aromatic molecules

Abstract

Carbon nanotubes (CNTs) are insoluble in small aromatics, but solubilisation is possible when special solubilisers are added to the solvent. The solubiliser molecules are composed of a large aromatic moiety, which adsorbs to the CNT, and a solvophilic group connected by a short aliphatic chain. The experimental finding that CNTs can be solubilised but not dissolved lets one assume that a strong interaction of the solubiliser molecules with the CNT is necessary for the solubilisation. The form of the solubiliser molecules and the need that the aromatic moiety must contain at least three condensed aromatic rings suggest that (1) the aromatic moiety interacts with the CNT, (2) the solvophilic group interacts with the bulk and (3) the solubilised CNTs are dressed by the strongly interacting solubiliser molecules. Strength of the interactions between CNT and the aromatic moiety can be described by either the interaction energy or the force needed to pull the aromatic molecule off the CNT. Although we do not find a size dependence of the desorption energies, we find a marked size dependence of the adhesive forces.

Keywords:

• dressed carbon nanotube
• aromatic molecules
• dispersion interaction
• desorption
• adhesive force
• interface properties

Acknowledgements

This study was an activity within the research core area Modeling and Simulation of the University of Graz.

Notes

^aStructures marked with a ^* are ‘nearly’ structures. See supplementary material.