European Physical Journal highlighted HI ERN publication
European Physical Journal (EPJ E) recently highlighted the study “Local electroneutrality breakdown for electrolytes within varying-section nanopores” from HI ERN scientist Paolo Malgaretti, and his colleagues. The researchers now derive equations that describe how local electrical charge in electrolytes changes in channels with varying cross sections, at equilibrium. The result could help to predict pathways for charged particles in biological and technological systems.
Plant vascular circulation, ion channels, our own lymphatic network, and many energy harvesting systems rely on the transport of dissolved salt solutions through tortuous conduits. These solutions, or electrolytes, maintain a positive or negative charge that’s vital to how the system functions. However, this charge balance depends on the properties of the channel that contains the fluid. In a study recently published in European Physical Journal (EPJ E), Paolo Malgaretti, Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN), and his colleagues, now derive equations that describe how local electrical charge in electrolytes changes in channels with varying cross sections, at equilibrium. The result could help to predict pathways for charged particles in biological and technological systems.
When an electrolyte solution is contained between two plates, theory says that the total electrical charge in the liquid should match that on the plates. However, Malgaretti et al.’s observations show that when the plates approach a separation of less than 10 nanometres from one another, this charge balance breaks down. Moreover, novel dynamics appear for electrolytes moving through asymmetric pores or channels of varying diameters.
To capture the interplay between geometry and local electrolyte charge balance, Malgaretti and his team performed calculations of an electrolyte embedded between corrugated channel walls. They found that the local charge was broken whenever the cross section of the channel changed. The researchers say that the onset of this excess charge results entirely from the interplay between channel geometry and electrostatic forces and is comparable to the total charge that built up on the walls.
More information
Read full article on EPJ E here and on the Springer Research News page.
Original publication
P. Malgaretti, I. Pagonabarraga, J. Harting. (2024), Local electroneutrality breakdown for electrolytes within varying-section nanopores. Eur. Phys. J. E 47, 15 (2024).
https://doi.org/10.1140/epje/s10189-024-00408-9
Contact
Dr. Paolo Malgaretti
Leader of the team "Dynamics of Confined and Chemically Reactive Fluids"
Room 5012