Modeling the Effects of Salt Concentration on Aqueous and Organic Electrolytes

van der Lubbe, S.; Canepa, P.

doi:10.1038/s41524-023-01126-0

Modeling the Effects of Salt Concentration on Aqueous and Organic Electrolytes

S. van der Lubbe and P. Canepa; npj Comput. Mater. 9, 175 (2023).

BibTeX

@article{Vanderlubbe2023modeling,
  author  = {van der Lubbe, S. and Canepa, P.},
  title   = {{Modeling the Effects of Salt Concentration on Aqueous and Organic Electrolytes}},
  journal = {npj Computational Materials},
  volume  = {9},
  pages   = {175},
  year    = {2023},
  doi     = {10.1038/s41524-023-01126-0}
}

Brief summary

How a salt solution departs from ideal behaviour, measured by its activity coefficient, matters from physiology to batteries, but the classical equations need data, the solution's permittivity and the size of its ions, that are rarely measured. We predict both with molecular dynamics and density functional theory, so the equations can be applied to any aqueous or organic electrolyte at any concentration and temperature.

Full abstract

Understanding the thermodynamic properties of electrolyte solutions is of vital importance for a myriad of physiological and technological applications. The mean activity coefficient γ_± is associated with the deviation of an electrolyte solution from its ideal behavior and may be obtained by combining the Debye-Hückel (DH) and Born (B) equations. However, the DH and B equations depend on the concentration and temperature-dependent static permittivity of the solution ε(c, T) and the size of the solvated ions r_i, whose experimental data is often not available. Here, we use a combination of molecular dynamics and density functional theory to predict ε(c, T) and r_i, which enables us to apply the DH and B equations to any technologically relevant aqueous and nonaqueous electrolyte at any concentration and temperature of interest.