Nanoheterogeneous surfaces in the control of interface phenomena

We have elaborated model heterogeneous molecular surfaces, which are characterized by the distribution of nanoscale domains of one molecular compound in a continuum of the second. Interestingly, it was found that the macroscopic equilibrium wetting parameters completely fail to account for the interface phenomena at these nanoheterogeneous surfaces, especially the dewetting behavior of confined thin films, as investigated in this work. Though strongly affected by the surface fraction and topological features at the nanoheterogeneous surfaces, the dewetting parameters (kinetics and morphology) do not show any direct correlation to the underlying surface patterns. Instead, a more subtle interplay between the bulk subphase property and the nanoscale top-layer chemistry is observed. On the basis of this interplay, the existence of two dynamic regimes, determined by the time-dependent film thickness ht, was demonstrated during the course of the dewetting process: the early-stage film destabilization dominated by the bulk-subphase property (long-ranged forces) and the late-stage film thinning,;nucleation, and hole growth, controlled by the top-layer chemistry (short-range forces and local effects at the wall).