Oversolubility in the microvicinity of solid-solution interfaces

Abstract : Water-solid interactions at macroscopic level (beyond ten of nanometers) are often viewed as the coexistence of two bulk phases with a sharp interface in many areas spanning from biology to (geo)chemistry and various technological fields (membranes, microfluidics, coatings, etc.). Here we present experimental evidence indicating that such a view may be a significant oversimplification. High-resolution infrared and Raman experiments were performed in a 60x20 μm2 quartz cavity, synthetically created and initially filled with demineralized water. The IR mapping (3x3 μm2 beam size) performed with the SOLEIL synchrotron radiation source displays two important features: (i) the presence of a dangling free-OH component, a signature of hydrophobic inner walls; (ii) a shift of the OH-stretching band which essentially makes the 3200 cm-1 sub-band to predominate over the usual main component around 3400 cm-1. Raman maps confirmed these signatures (though less marked than IR’s) and afford a refined spatial distribution of this interfacial signal. This spatial resolution, statistically treated, results in a puzzling image of a 1-3 μm thick marked-liquid layer along the entire liquid-solid interface. The common view is then challenged by these strong evidences that a μm-thick layer analogous to an interphase forms at the solid-liquid interface. The thermodynamic counterpart of the vibrational shifts amounts to around +1 kJ/mol at the interface with a rapid decreasing signature towards the cavity centre, meaning that vicinal water may form a reactive layer, micrometer thick, expected to have an elevated melting point, a depression of the boiling temperature, and enhanced solvent properties.
Document type :
Journal articles
Complete list of metadatas

Cited literature [36 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-01308355
Contributor : Nathalie Pothier <>
Submitted on : Wednesday, April 27, 2016 - 4:08:19 PM
Last modification on : Friday, May 10, 2019 - 1:54:16 PM
Long-term archiving on : Thursday, July 28, 2016 - 10:37:11 AM

File

c5cp08012f.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives 4.0 International License

Identifiers

Citation

Isabelle Bergonzi, Lionel Mercury, Patrick Simon, Frederic Jamme, Kirill Shmulovich. Oversolubility in the microvicinity of solid-solution interfaces. Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2016, 18, pp.14874-14885. ⟨10.1039/C5CP08012F⟩. ⟨insu-01308355⟩

Share

Metrics

Record views

389

Files downloads

141