Halide Ions Effects on Surface Excess of Long Chain Ionic Liquids Water Solutions
- Ames Laboratory
- Sogang University
The interfacial structure and composition of water solutions with alkylimidazolium ionic liquids varying in their halide anions ([C12mim][X], X = Cl and I) were investigated by X-ray near-total-reflection fluorescence spectroscopy and X-ray reflectivity measurements. We demonstrate that X-ray fluorescence and reflectivity techniques provide a more direct measurement of surface adsorption. Furthermore, we show that for [C12mim][Cl] and [C12mim][I] solutions with mixed inorganic salts (NaI, NaCl), I– ions replace Cl– above the critical micelle concentration (CMC) of [C12mim][Cl] at much lower concentrations of NaI, whereas NaCl concentrations a hundred times higher than the CMC of [C12mim][I] only partially replace the I– at the interface. Our surface-sensitive X-ray diffraction and spectroscopy provide two independent tools to directly determine the surface adsorption of ionic surfactants and the interfacial composition of the surface films.
- Research Organization:
- Ames Lab., Ames, IA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC02-07CH11358
- OSTI ID:
- 1132297
- Report Number(s):
- IS-J 8200
- Journal Information:
- Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry, Vol. 117, Issue 44; ISSN 1520-6106
- Publisher:
- American Chemical Society
- Country of Publication:
- United States
- Language:
- English
Similar Records
Isopiestic compositions of aqueous ionic surfactant systems as a measure of preferential interactions. Application to the determination of micelle aggregation numbers by equilibrium ultracentrifugation
Self-assembly of DNA functionalized gold nanoparticles at the liquid-vapor interface