Experimental study and molecular dynamics simulation of carbon nanotubes diffusion

Abstract

The diffusion of single-walled carbon nanotubes was studied experimentally and by the molecular dynamics method. The experiments used the dynamic light scattering method. Distributions and average values of diffusion coefficients of molecules of surfactants and nanotubes in nanofluids based on water were obtained. It was found that these distributions, even at low concentrations of nanotubes, can have two maxima corresponding to tubes of different sizes. The effect of centrifugation on the size distribution of nanotubes has been studied. The diffusion of one-dimensional and three-dimensional models of nanotubes in water has been studied by the molecular dynamics method. The velocity autocorrelation functions of of nanotubes of different lengths have been calculated. The presence of a negative region of these functions for small nanotubes has been established. The dependencies of the diffusion coefficient on the length are determined for both models used.