Sodium Halide Adsorption and Water Structure at the α-Alumina(0001)/Water Interface

Ruiyu Wang, Mark Dellostritto, Richard C. Remsing, Vincenzo Carnevale, Michael L. Klein, Eric Borguet

Research output: Contribution to journalArticlepeer-review

10 Scopus citations

Abstract

Alumina is one of the most abundant minerals and has a wide range of industrial applications, with catalysis as one of the most important. Of particular relevance for catalysis is the structure of the mineral/water interface. In this work, water structure and sodium halide adsorption at the neutral α-alumina(0001)/water interface are investigated using molecular dynamics simulations. This work demonstrates the accuracy of the chosen model of the alumina/water interface and shows that high charge density monovalent ions, such as Na+ and F-, have a strong affinity for the interface due to the specific pattern of alumina surface OH groups, such that the adsorbed ions displace waters that are hydrogen-bonded to the surface in their absence. A significant portion of the driving force for anion adsorption arises from surface bound Na+, which reverse the intrinsic surface dipole field and drive the accumulation of halides at the interface. The resulting electrolytic interfacial structure reorients water molecules as far as 1 nm from the surface. Although ion adsorption does not alter the global orientation of surface OH groups, it significantly affects their local geometry. This in turn may affect the reactivity of surface groups and thus play a role in chemical processes occurring at the interface.

Original languageEnglish (US)
JournalJournal of Physical Chemistry C
DOIs
StateAccepted/In press - 2019
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Fingerprint

Dive into the research topics of 'Sodium Halide Adsorption and Water Structure at the α-Alumina(0001)/Water Interface'. Together they form a unique fingerprint.

Cite this