Surface phase diagrams: Evidence of molecular arrangements at the aqueous-solution/solid interface
Résumé
Surface state changes described as phase transitions or simple molecular rearrangements have become a key issue in modern science. Indeed, they have an impact on the development of numerous (nano)-technologies; they are also involved in biochemical and chemical mechanisms at the molecular level and also in environmental phenomena. At last, they have been at the origin of flourishing statistical descriptions that have illuminated new and very interesting aspects of surface behaviors. Here, to obtain still lacking coherent sets of experimental data on systems in which molecular interactions and thermodynamic properties are different, the adsorption behaviors of three aqueous mixtures in contact with a dense and homogeneous silica were studied versus concentrations and temperatures. Of course, these mixtures displayed very different bulk phase properties. Their stairlike isotherms are interpreted through surface phase diagrams; each of them is very similar to the corresponding bulk phase diagram. Their comparison gives new insights into the different surface states, the role of solvent in the surface, and the probable molecular mobility.
Mots clés
Adsorption
Interfaces (materials)
Isotherms
Phase transitions
Solutions
Surface phenomena
Thermodynamic properties
Molecular interactions
Molecular rearrangements
Molecular-level mechanisms
Surface films
article
chemistry
solution and solubility
surface property
Nanotechnology
Phase Transition
Silicon Dioxide
Surface Properties
Temperature
Thermodynamics
Water
Adsorption
Interfaces
Phase Diagrams
Statistical Methods
Thermal Properties