Thrust 3 is motivated by three Research Questions:
1. What is the origin of universal, long-range correlations in confined, concentrated nanoparticle solutions in ionic aqueous media at equilibrium?
AMEWS is examining how such correlations affect transport properties (diffusion, viscosity, and normal stress coefficients) through pores. Recent calculations and experiments with simple aqueous solutions suggest that traditional descriptions of water and electrolytes at air/water interfaces are incomplete, and that electrolyte concentration is inhomogeneous at interfaces, with some effects attributed to polarizability. It is unclear how solid/water interfaces, including interfaces with nanoparticles will behave. Traditional descriptions of water in terms of two-body interactions are likely to be incomplete, and an important question is whether three-body effects are necessary to describe water and electrolyte solutions in neutral and charged pores, and in the gaps between charged nanoparticles.
2. Are correlations exacerbated or suppressed by flow and other applied external fields (e.g., voltage) as the system is driven away from equilibrium?
The effect that charged surfaces (or charged nanoparticle surfaces) might have on the range of such correlations in confined, aqueous electrolyte solutions is not known, and experimental reports have started to reveal intriguing behaviors. Conflicting experimental evidence suggests that transport coefficients for the particles and solvent could be significantly enhanced or severely suppressed by surface charges.
3. Can free energy landscapes can be engineered to directly interfere and manipulate ionic correlations in confined aqueous nanoparticle suspensions?
AMEWS seeks to determine whether it is possible to create purposely engineered charge patterns to control article localization, and whether it is possible, through dynamic interference by applied fields, to manipulate the resulting landscapes for applications.