Ion transport within Janus nanopores: Molecular Dynamics vs Continuum

Predictions of continuum theory are compared against extensive molecular dynamics simulations of a nanoscale Janus membrane performed with explicit ions and water molecules. The ‘Janus pore’ used here consists of three regions, each with a different diameter and charge, and application of a potential difference leads to complex arrangement of ions and non-trivial transport along the channel. These details are critical to the design and development of new power generation devices, such as the Janus membrane. We test ion distributions, solvent velocities, and electric current and report the agreement as well as important differences between the full atomistic and continuum calculation, of ions embedded in a dielectric continuum and driven by the coupling of Poisson electrostatics, Nernst-Planck transport, and Navier-Stokes hydrodynamics.