Amalie Frischknecht and Mark Stevens at Sandia developed new parameters to use in molecular dynamics simulations of zincate ions in aqueous potassium hydroxide solutions. The results were published in an article titled “Force Fields for High Concentration Aqueous KOH Solutions and Zincate Ions,” published March 28, 2024, in the American Chemical Society (ACS) Journal of Physical Chemistry B.
Many renewable energy technologies rely on aqueous alkaline electrolytes such as potassium hydroxide (KOH), including fuel cells, electrolyzers, and rechargeable zinc-based batteries. In the case of zinc batteries, zincate ions are also present in the electrolyte and cause problems if they cross the separator from one side of the battery to the other. Molecular simulations are a promising method to understand the details of ion and gas transport through these batteries, but to perform such simulations one first must know the interactions among all the species present, the so-called force field.
In this paper, the authors developed parameters for use in molecular dynamics (MD) simulations that are validated against experimental measurements of density and viscosity. This paper presents the first force field parameters for zincate available in the literature. These new force field parameters will enable future simulations of KOH-based electrolytes and dissolved zincate ions. This will be particularly helpful in understanding how polymer membranes can help to block the undesirable transport of zincate ions across zinc-based batteries while still allowing the high conductivity of hydroxide ions through the membrane needed for good device performance.
The American Chemical Society (ACS) Journal of Physical Chemistry B is a high-quality journal publishing fundamental results in physical chemistry, with an impact factor of 3.3.
Amalie Frischknecht and Mark Stevens are both staff scientists at the Center for Integrated Nanotechnologies at Sandia National Laboratories. This material is based upon work supported by the U.S. Department of Energy, Office of Electricity (OE), Energy Storage Division.
Amalie L. Frischknecht and Mark J. Stevens, “Force Fields for High Concentration Aqueous KOH Solutions and Zincate Ions,” J. Phys. Chem. B 2024, 128, 14, 3475-3484, DOI: 10.1021/acs.jpcb.3c08302.