The behaviour of fluoro- and hydrocarbon surfactants used for fabrication of superhydrophobic coatings at solid/water interface

The problem of surface energy reduction nowadays is easily solved by using fluorocarbon and hydrocarbon surfactants. The corresponding deposited surfactant film imparts superhydrophobic properties to the textured surfaces with multimodal roughness. However, to ensure the durability of superhydrophobic coatings, it is necessary that the surfactant molecules were irreversibly adsorbed onto the solid surface and showed chemical stability in contact with aqueous phases. Here, we show how the superhydrophobic coatings with fluorocarbon and hydrocarbon surfactants, having different chemical structure and different mechanism of binding to micro-nanotextured aluminium substrate behave in aqueous media with different pH and salinity during long-term contact. It is shown that all chosen hydrophobic agents demonstrate high stability in contact with water, however, for long-term contact with acidic and alkaline solutions, the appropriate choice of surfactant becomes of great importance for durability of the superhydrophobic coating. (C) 2015 Elsevier B.V. All rights reserved.