Effects of Surface Roughness and Electrostatic Surface Potentials On the Forces Between Dissimilar Surfaces In Aqueous Solutions

The rapid progress in the design and fabrication of smaller and smaller micro- and nanometer-scale devices requires a better fundamental understanding of, and the ability to control, the interfacial interactions between materials across ultra-small separation distances (< 100 nm). I will present Surface Forces Apparatus measurements under electrochemical potential control between a metal and a ceramic surface across an aqueous solution. These measurements show how the increasing level of surface roughness and electrochemical dissimilarity of the interacting surfaces influence the strength and range of the electrical double layer, van der Waals, hydration and steric forces, as well as the adhesion (pull-off) forces.