Surface phase diagrams: evidence of molecular arrangements at the aqueous-solution/solid interface.
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.
Andrieux
Dominique
D
UMR 6521-CR4, Département de Chimie, Université de Bretagne Occidentale, 6 avenue Le Gorgeu, C.S.93837 - 29238 Brest Cedex 3, France.
Acharid
Abdelhaq
A
Fritsch
Marie-Claire
MC
Marquez Garcia
Jose
J
Martin Martin
Marcos
M
Méar
Anne-Marie
AM
Sadiki
Mustapha
M
Huruguen
Jean-Pierre
JP
Olier
René
R
Privat
Mireille
M
D036103:Nanotechnology; D044367:Phase Transition; D012822:Silicon Dioxide / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*
D012996:Solutions; D014867:Water; D012822:Silicon Dioxide