Thermal Healing of a Mixed-Thiol Monolayer at the Nanoscale

Abstract

Using molecular dynamics simulation, we study the thermal healing of a mixed-thiol monolayer grown by contact printing. By simulating the monolayers with various compositions of octadecanethiol and decanethiol molecules, we show that a mixed-thiol monolayer grown by contact printing contains a significant portion of unbound molecules which fail to bind their sulfur atoms to the underlying gold surface. A subsequent thermal annealing (300–370 K) however removes the unbound thiol molecules and gives an ordered and compact monolayer. We uncover the molecular pathways behind the removal of the unbound molecules during thermal annealing.