Equilibrium and nonequilibrium transport of oxygen in carbon nanotubes

The equilibrium and nonequilibrium transport of O ₂ through open-ended, hydrogen-terminated, single-walled carbon nanotubes is examined using classical molecular dynamics simulations. It is found in both cases that the O ₂ forms well-defined layers around the nanotube interior and/or exterior, and that molecular transport approaches normal mode-diffusion as the nanotube diameter increases. The interactions between the O ₂ and the nantubes are stronger than that among the O ₂, and this difference increases as the nanotube diameter decreases.