Pumping of water by rotating chiral carbon nanotube.

Water transportation inside carbon nanotubes is of great importance for designing novel nanodevices. In this article, by using molecular dynamics simulations, we systematically investigate the pumping of water by rotating carbon nanotube (CNT). It is found that the chirality and rotation of the CNT are two preconditions for stable water flux inside it. Besides, we find that the water flux shows an approximately logarithmic dependence on the angular velocity of the rotation, a linear dependence on the radius of the CNT, and interestingly, independence of its length within a certain range of CNT size and angular velocity. Further, we also use a dragging theory which successfully describes the water flux behaviors inside the CNT and can fit well with the results obtained from simulations. The present study provides insight into the designing of nanodevices based on the CNT for real applications.