posted on 2017-07-20, 00:00authored byWen Li, Wensen Wang, Yingnan Zhang, Youguo Yan, Caili Dai, Jun Zhang
Understanding
and controlling water or ion transport in nanochannels
plays an important role in further unravelling the transport mechanism
of biological membrane channels and designing functional nanofluidic
devices. Molecular dynamics simulations were conducted to investigate
water and ion transport in graphene nanochannels. Similar to electron
coulomb blockade phenomenon observed in quantum dots, we discovered
an ionic coulomb blockade phenomenon in our graphene nanochannels,
and another two ion transport modes were also proposed to rationalize
the observed phenomena under different electric-field intensities.
Furthermore, on the basis of this blockade phenomenon we found that
the Open and Closed states of the graphene nanochannels for water
transport could be switched according to external electric-field intensities,
and electroosmotic flow could further enhance the water transport.
These findings might have potential applications in designing and
fabricating controllable valves in lab-on-chip nanodevices.