Molecular dynamics simulations on water permeation through hourglass-shaped nanopores with varying pore geometry

- Molecular dynamics simulations were performed for hourglass-shaped pores.
- The effect of varying cone angle and cylinder length on water transport was studied.
- The optimization of pore geometry provides a basis for improving water transport.

We investigate the transport of water in hourglass-shaped nanopores using molecular dynamics (MD) simulations. We focus on the hydrodynamic effect by exploiting conical entrance/exit effects and utilizing the single-file fast water flow by limiting the cylinder diameter. We assume that the transport ability facilitated by the hourglass-shaped nanopores can be improved by varying the combination of cone angle and cylindrical pore length. The maximized results for transport properties with geometric parameters, quantified as number flux and osmotic permeability, prove that our assumption is reasonable. Further analysis for the validity of our design concerns the distribution of water inside the pore, e.g., the friction force between water molecules and the pore. Maximization of pore geometry provides a basis for improving the flux and velocity of water transport through nanoscale structural design.