Electrokinetic non-equilibrium effects in transient nanopores

• Applicants: Professor Dr. Steffen Hardt; Professor Dr. Benno Liebchen
• Subject Area: Fluid Mechanics ; Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 509491635

This subproject has an overarching character in TRANSIEVES and is intended to provide model descriptions for the lead experiments. The purpose of these model descriptions is to help to identify and understand the fundamental physics of species transport through transient sieves, as well as to identify “sweets spots” in the parameter space. These sweet spots are regions in which species separation becomes especially efficient. Such information will be invaluable for the lead experiments. In addition, subproject B4 explores novel concepts of species separation by transient sieves which are likely to excite experimental activities in the second funding period of the Research Unit. More exactly, we intend to develop minimal models that are based, among others, on the relevant dimensionless parameters of a specific problem. The first novel concept for species separation we would like to explore is based on conical nanopores with gate electrodes energized by an AC voltage. In such pores, species separation should become possible by exploiting a competition between advective and diffusive transport. The second novel concept is based on the observation that in an electrolyte with anions and cations of different electrophoretic mobilities, electrodes energized with an AC voltage of zero time average can produce a non-vanishing, time averaged electric field in the electrolyte. We would like to explore to what extent the emerging electric field can serve as a potential barrier that can be used for species separation. Last but not least, we would like to build a model related to the experimental activities of lead experiment A1. In this experiment, species transport through self-renewing liquid pores will be studied. The model will have a reduced order character and will complement the numerical simulations of subproject B2.

• DFG Programme: Research Units
• Subproject of: FOR 5584: Transient Sieves