Molecular separation with carbon nanotubes

The feasibility of molecular separation with carbon nanotubes is studied by investigating a separation of water molecules and lead nanoparticles with a carbon nanotube-based nanopore system from molecular dynamics simulations. The nanopore system is comprised of a single-walled carbon nanotube and two graphene sheets placed at two ends of the nanotube. The nanotube is subjected to impact loads on a local portion on the wall to generate the propagation of impulse waves in the tube for pumping the encapsulated water molecules out of the tube, while blocking lead nanoparticles by the two graphenes. Studies indicate that the separation is a result of van der Waals interactions between the nanotube and the encapsulated molecules through the propagation of impulse waves in the nanotube. The efficiency of the molecular separation is found to be dependent on the amount of impact loads and the size of the impacted portion of the tube. © 2014 Elsevier B.V. All rights reserved.