5 research outputs found
Schematic chemical structure of the lipid and ionic liquids studied in this work.
<p>Schematic chemical structure of the lipid and ionic liquids studied in this work.</p
Mean diameter and half-width of the size distribution of DMPC vesicles incubated in the presence of ILs.
<p>The number in parentheses is the polydispersity index.</p
Overview of the time dependence of the Îf/n and ÎD responses of systems containing 30 mM and 100 mM [C<sub>4</sub>mim]Cl, [C<sub>8</sub>mim]Cl and [C<sub>10</sub>mim]Cl onto a gold-coated QCM-D quartz sensor.
<p>Results are displayed for overtone 7<sup>th</sup>.</p
Nanomechanical Stability of Laterally Heterogeneous Films of Corrosion Inhibitor Molecules Obtained by Microcontact Printing on Au Model Substrates
Self-assembled
monolayers of corrosion inhibitors of the mercaptobenzimidazole
family, SH-BimH, SH-BimH-5NH2, and SH-BimH-5OMe, were formed
on template-stripped ultraflat Au surfaces using microcontact printing,
and subsequently analyzed using X-ray photoelectron spectroscopy (XPS),
atomic force microscopy (AFM), and AFM-force spectroscopy (AFM-FS)
using a quantitative imaging (QI) mode. Printing of all used inhibitor
molecules resulted in clear patterns and in slightly more compact
films compared to immersion. The stability of the monolayers is further
probed by AFM-FS. Adhesion values of laterally heterogeneous inhibitor-modified
surfaces compared to bare Au surfaces, nonpatterned areas, and fully
covered surfaces are analyzed and discussed. Microcontact printing
confers a superior nanomechanical stability to imidazole-modified
films of the printed surface patches as compared to homogeneously
covered surfaces by immersion into the inhibitor solution
Initiation and Inhibition of Dealloying of Single Crystalline Cu<sub>3</sub>Au (111) Surfaces
Dealloying is widely utilized but is a dangerous corrosion process as well. Here we report an atomistic picture of the initial stages of electrochemical dealloying of the model system Cu<sub>3</sub>Au (111). We illuminate the structural and chemical changes during the early stages of dissolution up to the critical potential, using a unique combination of advanced surface-analytical tools. Scanning tunneling microscopy images indicate an interlayer exchange of topmost surface atoms during initial dealloying, while scanning Auger-electron microscopy data clearly reveal that the surface is fully covered by a continuous Au-rich layer at an early stage. Initiating below this first layer a transformation from stacking-reversed toward substrate-oriented Au surface structures is observed close to the critical potential. We further use the observed structural transitions as a reference process to evaluate the mechanistic changes induced by a thiol-based model-inhibition layer applied to suppress surface diffusion. The initial ultrathin Au layer is stabilized with the intermediate island morphology completely suppressed, along an anodic shift of the breakdown potential. Thiol-modification induces a peculiar surface microstructure in the form of microcracks exhibiting a nanoporous core. On the basis of the presented atomic-scale observations, an interlayer exchange mechanism next to pure surface diffusion becomes obvious which may be controlling the layer thickness and its later change in orientation