The Journal of Physical Chemistry C · 2016 · 50 citations · 45 references
Natural SciencesMaterials SciencePhysicsMaterials PhysicsSurface ChemistrySurface ScienceAdsorption At InterfacesAtomic Force MicroscopyIon-conducting MaterialsSurface AdsorptionSurface CrystallographySurface PhysicsAdsorbate - Surface InteractionsAdsorbate InteractionsAdsorption GeometryElectrode Surface StructureEpitaxial InterfacesIon Adsorption DynamicsMolecular Orientation At SurfacesPotential-dependent Adsorption
The molecular arrangement and surface dynamics of Au (111) electrodes in 1-hexyl-3-methylimidazolium chloride ([HMIm][Cl]) and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIm][TFSA]) were investigated by in situ high-speed scanning tunneling microscopy (video-STM). These measurements provide direct insights into the potential-dependent adlayer structure of adsorbed [HMIm] + cations and Cl – anions on the Au (111) surface. At low electrode charge densities highly dynamic structures with only local order are observed. After changing the potential in the negative direction, stripe-like adlayers structures are observed, which are attributed to [HMIm] + in a planar adsorption geometry. These can be described by simple commensurate (√3 × 3) and a (√3 × √13) structures in the presence of Cl – and [TFSA] − counterions, respectively, indicating that the in-plane arrangement of the cations is affected by epitaxial effects and coadsorbed anions. Upon a further decrease in potential, a transition to a more close-packed (√3 × 2) adlayer phase is observed in [HMIm][TFSA], in which the cations are partly oriented away from the metal surface.
45
Molecular Layering of Fluorinated Ionic Liquids at a Charged Sapphire (0001) Surface
Markus Mezger, Heiko Schröder, H. Reichert et al. · Science · 2008 · 644 citations
Vera Lockett, Rossen Sedev, John Ralston et al. · The Journal of Physical Chemistry C · 2008 · 508 citations