Cross-Sectional Structure of Liquid 1‑Decanol over Graphite

Abstract

The interface of graphite and liquid 1-decanol was studied using frequency modulation atomic force microscopy (FM-AFM). The topography of epitaxially physisorbed decanol on the substrate was traced with submolecular resolution. The tip–surface force was monitored in the liquid as a function of the vertical and lateral tip coordinates to reveal the cross-sectional structure of the interfacial decanol. Four or more liquid layers were identified by vertically modulated force distributions. The first and second liquid layers were laterally heterogeneous, as evidenced by a force distribution that was periodically modulated along lateral coordinates. A possible structuring mechanism is proposed on the basis of energy gain by hydrogen bonding and van der Waals interactions