Widely available clean water is one of the greatest current and future global challenges. Water is essential for life and it is a key-factor in many technological and biological processes. This research, which focuses on interfacial/confined water flow, will have a direct impact not only in separation and water filtration processes but also in understanding lubrication processes, membrane hydration in fuel cells, and the molecular interaction of water with cell membranes and in biological pores. This project will produce fundamental understanding of the nanoscale physics and chemistry of the interface between aqueous solutions and solid surfaces for the purpose of developing new desalinization systems based on nanoporous membranes. A critical knowledge gap in using nanoscale materials, is the understanding of the solid-liquid interactions at the nanoscale, which differ from those of the bulk phase. New models of fluid transport at the nanoscale are expected to emerge from this research. The broader impacts of this project include educational activities, which will take place at the Advanced Science Research Center (ASRC), which is a brand new multi-disciplinary center in NYC. Collaborations between the ASRC, CUNY colleges, and Columbia University are at the core of this center, whose goal is to support scholarship and student learning at multiple levels.
Membranes and porous materials with pore size in the sub-nanometer scale are important for separation processes, such as water desalination. The project's long-term goal is to generate novel nanoporous membranes based on layered materials such as those based on graphene oxide, graphene, boron nitride, and molybdenum disulfide. The project will combine the use of advanced scanning probe microscopy methods of model aqueous solutions and model nanoporous membranes with molecular dynamics computer simulations to determine how the properties of aqueous solutions, e.g. ion concentration, ion specificity, presence of co-solvents and other solutes, and the complexity of the interfacial surface, e.g. degree of confinement, functional groups, chemistry, heterogeneity, presence of electric fields, influence the structure, ions arrangement, viscosity, viscoelasticity, slip, electro-kinetics, and flow of water/ions solutions at solid/liquid interfaces. All this information will help inform the design of desalination membranes with improved permeability and improved understanding of the impact of membrane surface chemistry and also of adjoining solution chemistry and their rheological properties.
