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A Microfluidic Approach for the Study of Ice and Clathrate Hydrate Crystallization
Published on: August 18, 2022
Hydroxide impurity in ice.
Lukasz Cwiklik1, J P Devlin, Victoria Buch
1The Fritz Haber Institute for Molecular Dynamics, The Hebrew University, Jerusalem 91904, Israel. lukasz@fh.huji.ac.il
The Journal of Physical Chemistry. A
|April 17, 2009
Summary
Hydroxide ions (OH-) in water ice I can halt proton mobility by binding to specific traps. However, proton activity resumes when these traps become saturated with sufficient hydroxide ions.
Area of Science:
- Physical Chemistry
- Surface Science
- Materials Science
Background:
- Proton mobility in water ice is crucial for various chemical and physical processes.
- Understanding the influence of adsorbates on proton transport is essential for ice science.
Purpose of the Study:
- To investigate the role of hydroxide ions in proton mobility within water ice I.
- To elucidate the mechanism by which base adsorbates affect proton activity at ice surfaces.
Main Methods:
- Computational methods, specifically density functional theory (DFT) calculations on ice slabs.
- Experimental isotopic exchange experiments on ice nanoparticles.
Main Results:
- Base adsorbates on ice surfaces significantly influence proton activity.
- Trace amounts of base adsorbates inhibit proton activity by trapping hydroxide ions (OH-).
- Increased adsorbate concentration restores proton activity by saturating the hydroxide ion traps.
Conclusions:
- Strong binding sites for hydroxide ions exist at the ice surface and interior, immobilizing them and halting proton mobility.
- Proton activity is restored when these deep traps are saturated by a sufficient abundance of hydroxide ions.
- Hydroxide ions exhibit a broad energy distribution when located at different lattice sites in ice.
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