PhD position in Nanoscience

Project title: Sliding friction in liquid environments: A nanotribology study

Understanding the influence of the surrounding environment on the sliding friction between two solid surfaces in liquids is of utmost importance for applications to MEMS/NEMS or colloidal systems as well as to shed light on the dynamics of formation and rupture of single contact junctions. In this project we aim to perform an experimental investigation of the mechanical properties of contacts formed by sharp silicon tips on solid surfaces with different degrees of complexity using friction force microscopy. The sample surfaces will be exposed to electrolyte aqueous solutions and to polar and nonpolar solvents with varying viscosities. The different interaction potentials will be quantitatively reconstructed from the time variations of the friction forces acting on the tip with original numerical techniques. The results so obtained will be compared to complementary information obtained with dynamic AFM modes.