Ion-Specific and pH-Dependent Hydration of Mica-Electrolyte Interfaces

Hydration forces play a crucial role in a wide range of phenomena in physics, chemistry, and biology. Here, we study the hydration of mica surfaces in contact with various alkali chloride solutions over a wide range of concentrations and pH values. Using atomic force microscopy and molecular dynamic...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 35(2019), 17 vom: 30. Apr., Seite 5737-5745
1. Verfasser: van Lin, Simone R (VerfasserIn)
Weitere Verfasser: Grotz, Kara K, Siretanu, Igor, Schwierz, Nadine, Mugele, Frieder
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2019
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't
Beschreibung
Zusammenfassung:Hydration forces play a crucial role in a wide range of phenomena in physics, chemistry, and biology. Here, we study the hydration of mica surfaces in contact with various alkali chloride solutions over a wide range of concentrations and pH values. Using atomic force microscopy and molecular dynamics simulations, we demonstrate that hydration forces consist of a superposition of a monotonically decaying and an oscillatory part, each with a unique dependence on the specific type of cation. The monotonic hydration force gradually decreases in strength with decreasing bulk hydration energy, leading to a transition from an overall repulsive (Li+, Na+) to an attractive (Rb+, Cs+) force. The oscillatory part, in contrast, displays a binary character, being hardly affected by the presence of strongly hydrated cations (Li+, Na+), but it becomes completely suppressed in the presence of weakly hydrated cations (Rb+, Cs+), in agreement with a less pronounced water structure in simulations. For both aspects, K+ plays an intermediate role, and decreasing pH follows the trend of increasing Rb+ and Cs+ concentrations
Beschreibung:Date Completed 25.06.2020
Date Revised 23.07.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.9b00520