Interactions between conducting surfaces in salt solutions

Summary, in English

In this work, we simulate interactions between two perfectly conducting surfaces, immersed in a salt solution. We demonstrate that these forces are quantitatively different from those between (equally charged) non-conducting surfaces. There is, for instance, a significant repulsion between net neutral surfaces. On the other hand, there are also qualitative similarities, with behaviours found with non-conducting surfaces. For instance, there is a non-monotonic dependence of the free energy barrier height, on the salt concentration, and the minimum essentially coincides with a flat profile of the apparent surface charge density (i.e. the effective net surface charge density, some distance away from the surface, when accounting for ion neutralization), outside the so-called Stern layer. These conditions can be described as "perfect surface charge neutralization". Despite observed quantitative differences, we demonstrate that it might be possible to mimic a dispersion containing charged colloidal metal particles by a simpler model system with charged non-conducting particles, using modified particle-ion interactions. This journal is

• Author: Samuel Stenberg; Clifford E. Woodward; Jan Forsman
• Department/s: Computational Chemistry
• Publishing year: 2022-02-28
• Language: English
• Pages: 1636-1643
• Publication/Series: Soft Matter
• Volume: 18
• Issue: 8
• Links: http://dx.doi.org/10.1039/d1sm01520f
• Document type: Journal article
• Publisher: Royal Society of Chemistry
• Topic: Physical Chemistry (including Surface- and Colloid Chemistry)
• Status: Published
• ISBN/ISSN/Other: ISSN: 1744-683X