Related papers: Interfacial structure and boundary lubrication of …
Ionic liquids, salts in the liquid state under ambient conditions, are of great interest as precision lubricants. Ionic liquids form layered structures at surfaces, yet it is not clear how this nano-structure relates to their lubrication…
Recent reports of surface forces across nanoconfined ionic liquids have revealed the existence of an anomalously long-ranged interaction apparently of electrostatic origin. Ionic liquids are viscous and therefore it is important to inspect…
Hydrocarbon films confined between smooth mica surfaces have long provided an experimental playground for model studies of structure and dynamics of confined liquids. However fundamental questions regarding the phase behavior and shear…
Liquid crystals have emerged as potential candidates for next-generation lubricants due to their tendency to exhibit long-range ordering. Here, we construct a full atomistic model of 4-cyano-4-hexylbiphenyl (6CB) nematic liquid crystal…
Experimental investigations of surface forces generally involve two solid bodies of simple and well-defined geometry interacting across a medium. Direct measurement of their surface interaction can be interpreted to reveal fundamental…
Ionic liquids have generated interest in applications as lubricants and as additives to conventional lubricants due to their unique physical properties. In these applications, the liquid thin film can be subjected simultaneously to…
We study the effect of atomic scale surface-lubricant interactions on nanoscale boundary-lubricated friction, by considering two example surfaces - hydrophilic mica and hydrophobic graphene - confining thin layers of water in molecular…
Using a dynamic Surface Force Apparatus, we demonstrate that the notion of slip length used to describe the boundary flow of simple liquids, is not appropriate for viscoelastic liquids. Rather, the appropriate description lies in the…
We investigate nanoscale friction in [LaMnO3]m/[SrMnO3]n superlattice films using lateral force microscopy, focusing on the effects of fluorine doping and top-layer thickness. For all samples, friction forces scale linearly with the sum of…
We investigate the structure of the [bmim][Tf2N]/silica interface by simulating the indentation of a thin (4 nm) [bmim][Tf2N] film by a hard nanometric tip. The ionic liquid/silica interface is represented in atomistic detail, while the tip…
Ionic Liquids feature thermophysical properties that are of interest in solvents, energy storage materials and tenable lubrication applications. Recently, a series of coarse grained (CG) models was developed to investigate…
The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer…
This work describes the behaviour of water molecules in 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid under nanoconfinement between graphene sheets. By means of molecular dynamics simulations, an adsorption of water molecules…
Liquids in contact with solids are submitted to intermolecular forces making liquids heterogeneous and, in a mechanical model, the stress tensor is not any more spherical as in homogeneous bulks. The aim of this article is to show that a…
The slipperiness of ice is an everyday-life phenomenon which, surprisingly, remains controversial despite a long scientific history. The very small friction measured on ice is classically attributed to the presence of a thin…
Using non-equilibrium molecular dynamics simulations and a coarse grained model of ionic liquids, we have investigated the impact that the shape and the intramolecular charge distribution of the ions have on the electrotuneable friction…
We report on the frictional properties of thin ($\approx \mu m$) poly(dimethylacrylamide) hydrogel films within contacts with spherical silica probes. In order to focus on the contribution to friction of interfacial dissipation, a dedicated…
Nanofluidic transport is ubiquitous in natural systems from extra-cellular communication in biology to geological phenomena, and promotes the emergence of new technologies such as energy harvesting and water desalination. While experimental…
The confinement of an ionic liquid between charged solid surfaces is treated using an exactly solvable 1D Coulomb gas model. The theory highlights the importance of two dimensionless parameters: the fugacity of the ionic liquid, and the…
The dielectric constant of interfacial water has been predicted to be smaller than that of bulk water (= 80) because the rotational freedom of water dipoles is expected to decrease near surfaces, yet experimental evidence is lacking. We…