Self-Assembly of Aqueous Surfactants On Patterned Surfaces: Insights From Coarse-Grained Simulations

The adsorption and self-assembly of surfactants are ubiquitous processes in several technological applications. From a fundamental point of view, understanding such processes is also important because it can have profound implications in the manufacture of nano-structured materials using bottom-up strategies. Although a lot is known about the adsorption of surfactants on homogeneous flat surfaces, limited information is available, in quantifiable terms, regarding the adsorption of surfactants on heterogeneous surfaces. To complement and enrich our recent experimental observations [Langmuir 27 (2011) 6091], we report here our first results obtained using dissipative particle dynamics simulations for the adsorption of model surfactants on patterned flat surfaces. The results show that the surface pattern can be used to direct the morphology of the self-assembled aggregates (flat monolayers, hemi-cylinders, hemi-spheres, hollow hemi-cylinders, and irregular structures have all been observed using the same surfactant but different surface patterns). We will discuss how our predictions could be tested experimentally, and how, if reliable, they could be used for the design of new materials.