Effect of the direction of static electric fields on water transport through nanochannels

The transport properties of water molecules through single-walled carbon nanotubes (SWCNT) under static electric fields (SEFs) with different directions were studied by molecular dynamics simulations. It is found that the net water flux in the SEF direction opposite to the hydrostatic pressure direction is much larger than that in the same direction under the electric field intensity 0.01 < E-0 <= 0.6 V/nm. The reason is mainly that the SEF tunes the polarization direction of the water chain in the SWCNT, leading to different barrier height to be overcome for water molecules channeling across the SWCNT. Further, it also implies that water molecule chains moving forward with the oxygen atom can pass through the nanotube faster than that with the hydrogen atom forward. These findings may be instructive to regulate the water transport properties using the SEF in nanofluid devices and biological nano-channels.

Automated summary

The transport properties of water molecules through single-walled carbon nanotubes under static electric fields were studied through molecular dynamics simulations. The research found that the net water flux is much larger in the direction opposite to the hydrostatic pressure under certain electric field intensities. This is mainly attributed to the electric field tuning the polarization direction of the water chain in the nanotube, affecting the barrier height for water molecules to pass through. Additionally, water molecule chains moving forward with oxygen atoms can pass through the nanotube faster than those with hydrogen atoms.