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When a gecko moves on a ceiling it makes use of adhesion and stiction. Stiction--static friction--is experienced on microscopic and macroscopic scales and is related to adhesion and sliding friction (1). Although important for most locomotive processes, the concepts of adhesion, stiction and sliding friction are often only empirically correlated. A more detailed understanding of these concepts will, for example, help to improve the design of increasingly smaller devices such as micro- and nanoelectromechanical switches (2). Here we show how stiction and adhesion are related for a liquid drop on a hexagonal boron nitride monolayer on rhodium (3), by measuring dynamic contact angles in two distinct states of the solid-liquid interface: a corrugated state in the absence of hydrogen intercalation and an intercalation-induced flat state. Stiction and adhesion can be reversibly switched by applying different electrochemical potentials to the sample, causing atomic hydrogen to be intercalated or not. We ascribe the change in adhesion to a change in lateral electric field of in-plane two-nanometre dipole rings (4), because it cannot be explained by the change in surface roughness known from the Wenzel model (5). Although the change in adhesion can be calculated for the system we study (6), it is not yet possible to determine the stiction at such a solid-liquid interface using ab initio methods. The inorganic hybrid of hexagonal boron nitride and rhodium is very stable and represents a new class of switchable surfaces with the potential for application in the study of adhesion, friction and lubrication., Every object at rest sticks with some adhesion to its substrate. If this object is moved, then a force must act on it. This force has to overcome the stiction [...]

An electrochemical STM setup was employed to study the electron transport characteristics in redox molecule-modified tunneling junctions Au(111)/6-thiohexanoylferrocene (Fc6)/solution gap/Au STM tip in the absence and in the presence of gold nanoclusters. The results demonstrated the power of the electrochemical approach in molecular electronics and offered a new perspective toward two-state and multistate electronic switching in condensed media at room temperature.

Study is conducted to show that individual nanoparticles can be operated as multistate switches in condensed media at room temperature, displaying distinct peak features in the tunneling current. The tunneling conductance increases with particle charge, suggests that solvent reorganization and dielectric saturation become increasingly important.

An efficient strategy for the specific immobilization of fully functional proteins onto the surface of nanoparticles is described. The absence of nonspecific protein adsorption and the specificity of the binding site are verified using several analogues of the enzymes without the histidine tag.