Electric Double Layer at the Rutile (110) Surface. 2. Adsorption of Ions from Molecular Dynamics and X-ray Experiments

0340730 - ÚCHP 2010 RIV US eng J - Journal Article
Předota, Milan - Zhang, Z. - Fenter, P. - Wesolowski, D.J. - Cummings, P.T.
Electric Double Layer at the Rutile (110) Surface. 2. Adsorption of Ions from Molecular Dynamics and X-ray Experiments.
Journal of Physical Chemistry B. Roč. 108, č. 32 (2004), s. 12061-12072. ISSN 1520-6106. E-ISSN 1520-5207
R&D Projects: GA ČR GP203/03/P083; GA ČR GA203/02/0805
Institutional research plan: CEZ:AV0Z4072921
Keywords : ion * adsorption * rutile
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 3.834, year: 2004

Molecular dynamics simulations were conducted to characterize the microstructure of the interface between aqueous solutions and the (110) surface of rutile (alpha-TiO2) for hydroxylated and nonhydroxylated surfaces, each either neutral or negatively charged. The fully atomistic description of the rutile surface and its interactions with the fluid phase was based on ab initio calculations, while the aqueous phase was described by the SPC/E model and existing parameterizations for Rb+, Na+, Sr2+, Zn2+, Ca2+, and Cl- ions. Simulation results agree very well with X-ray standing wave and crystal truncation rod studies of the inner sphere adsorption sites of the cations Rb+ and Sr2+. MD and X-ray results for Zn2+ adsorption are qualitatively consistent, but important differences in adsorption heights are discussed. The hydroxylated surface gives better agreement with experiments than the nonhydroxylated surface, and is therefore inferred to be the dominant surface.
Permanent Link: http://hdl.handle.net/11104/0005777