Optimizing the Interactions of Surfactants with Graphitic Surfaces and Clathrate Hydrates.

Abstract

Surfactants are amphiphilic molecules active at the surface/interface and able to self-assemble. Because of these properties, surfactants have been extensively used as detergents, emulsifiers, foaming agents, and wetting agents. New perspectives have been opened by the exploitation of surfactants for their capacity to interact as well with simple molecules or surfaces. This feature article gives an overview of significant contributions in the panorama of the current research on surfactants, partly accomplished as well by our research group. We look at several recent applications (e.g., adsorption to graphitic surfaces and interactions with hydrate crystals) with the eye of physical organic chemists. We demonstrate that, from the detailed investigation of the forces involved in the interactions with hydrophobic surfaces, it is possible to optimize the design of the surfactant that is able to form a stable and unbundled carbon nanotube dispersion as well as the best exfoliating agent for graphitic surfaces. By studying the effect of different surfactants on the capacity to favor or disfavor the formation of a gas hydrate, it is possible to highlight the main features that a surfactant should possess in order to be devoted to that specific application.