The Effect of Wettability on the Dynamical Behaviors of Single-Walled Carbon Nanotube

Abstract

The dynamical behaviors of single-walled carbon nanotube (SWCNT) with the internal and external wettability are studied based on a multiple flexible shell model in the paper. The SWCNT-water system comprises five constituent parts, that is, the SWCNT, the absorbed inner and outer layers of water molecules, the water in the center of the SWCNT, and the water surrounding the absorbed outer water layer. Here we consider the absorbed water layers as infinitesimally thin shells, which interact with the nanotube via a continuum Lennard-Jones potential, and the water in the center of the SWCNT and the counterpart surrounding the absorbed outer water layer as the potential flow. It is found that the interactions of SWCNT and the water layer are responsible for an upshift in the frequency of the SWCNT and the total upshift is approximately the sum of the two corresponding upshifts. The vdW interactions also cause the increase of the frequency of internal and external water shells. We hope that the paper can offer a new modeling approach to determine whether carbon nanotubes have adsorbed fluids inside their pores and could be used for detecting changes in their filling state.