Graphene nanoribbon-guided fluid channel: a fast transporter of nanofluids

Abstract

In this work, we present a conceptual design of nanofluid channels using graphene sheets as the container and nanoribbons as flow guiders. Using molecular dynamics simulations, we demonstrate that water molecules confined in such nanochannels can be well guided by the nanoribbons and form a regular shaped water stream. The viscosity of water transported along such nanochannels is found to be orders of magnitude lower than that of bulk water. Several unconventional structural and flow characteristics are revealed to be responsible for the fast transport phenomenon comparable to that in carbon nanotubes. The proposed nanoribbon-guided fluid channel is promising for use in next-generation integrated material systems for transporting fluids at high volumetric flow rates with considerably low driving forces.

Channel morphology effect on water transport through graphene bilayers

“…These three quantities are closely correlated11429. The effective shear force can be estimated as τ  =  Nma / S , where N is the total number of water molecules inside the channel, m the atomic mass of a water molecule, and S the contacting area between water and the GE wall.…”

“…Previous studies have demonstrated that when confined in nanochannels with sizes ranging from sub-nanometer to several nanometers, fluids can exercise unconventional and sometimes even counterintuitive behaviors121314151617. Such behaviors are mainly due to the fact that the interactions among the fluid ions or molecules change dramatically when they are in close contact with the confining walls1518.…”

“…Such behaviors are mainly due to the fact that the interactions among the fluid ions or molecules change dramatically when they are in close contact with the confining walls1518. Both molecular simulations and experimental works have revealed that the flow rate of water through a few layered GE is orders of magnitude higher than that predicted by the conventional Hagen-Poiseuille law71419. This high transport rate has been attributed to the inherent smoothness of the interior wall of the GE layers and the high capillary driving pressure induced by the narrow nanochannels714.…”

Directional transport of molecular mass on graphene by straining

“…Our proposed mechanism can be feasibly extended to design other potential directional motion actuation scheme. For example, two graphene planes forming a channel has been proposed as nanofluid channels [45][46][47][48]. As a simple demonstration for such application, we show that strain engineered graphene nanochannel can offer intrinsic actuation force that can potentially pump the molecules moving from one end of the channel to another.…”

Fluidic behaviours in a 2D folded-graphene aerogel monolith

“…In the experiments on the 2D nanoslits, the driving pressure is only one third of that in 1D nanotubes and the conduction plateau becomes flat fast. Compared with the axial constraints of 1D nanotubes, 2D nanoslits [44] or nanoribbons [45] relaxed the constraints from the lateral directions on the confined water molecules, and the additional degree of freedom allowed the confined water molecules to reach a lower system free energy, promoting the formation of more energetically favourable molecular configurations with little interlayer resistance in 2D nanoenvironments.…”