(318c) Adsorption and Self-Assembly of Surfactant Molecules on Metallic Surfaces Studied Using Molecular Simulations

Surfactant molecules are known to adsorb and self-assemble on to metal-water interfaces. While adsorbed surfactant films are employed for many technological applications, such as corrosion inhibition and electrochemical blocking of electrodes, the molecular nature of this phenomenon is only poorly understood. From our coarse-grained simulations, we reveal that the traditional depiction of surfactant adsorption is imprecise on many fronts. We show that lateral interactions between alkyl tails of surfactant molecules play an important role in adsorption and self-assembly; the nature of the adsorbed morphology of surfactant films depends on molecular geometry; the adsorbed surfactant films are patchy with a significant fraction of the polar heads pointing towards the solution; and the magnitude of the free energy barrier to formation of self-assembled monolayers depends on the strength of polar group – surface affinity. These results, along with their implications in optimal design of surfactant molecules for different applications, will be discussed in this talk.