Water and Molecule Transport Through 2D Nanopores and Nanochannels

The molecular transport phenomena within nanometer-scales constrictions is important for understand basic biological and physical processes, as well as for the rational design of materials for energy and water technologies. 2D materials offer a good model system, with atomically smooth interfaces, sub-nanometer control of geometry, and fine control of surface charges and functionalization.<br/>In this presentation, I will discuss the transport of water and molecules across nanopores in 2D membranes, atomically smooth 2D nanochannels, and laminar graphene-based membranes. Employing a novel micro-pervaporation chamber, we could measure nanoscale transport of liquids and mixtures – through individual nanopores of 10 – 100 nm in diameter, and 1 – 50 nm high nanochannels – at variable temperature, and we could detect differential fluxes of each component. Comparing different 2D materials, and different liquids and binary mixtures, we could discern the effects of geometry vs. materials properties, and deduce the contribution of surface mediated transports. Highly enhanced flux of water is strongly affected by inclusion of different type of alcohol molecules, leading to either alcohol-water correlations, or alcohol-induced anchoring of water molecules. Those nanoscopic insights allowed us to develop the scaled-up membranes with superior molecular separation properties.