Superhydrophilic and superhydrophobic nanostructured surfaces via plasma treatment

Polyethylene terephthalate (PET) films have been structured with isolated nanofibrils and fibril bundles using oxidative plasma treatments with increasing etching ratios. The transition from fibrils to bundles was smooth and it was associated with a significant reduction in the overall top area fraction and with the development of a second organisation level at a larger length scale. This increased complexity was reflected in the surface properties. The surfaces with two-level substructures showed superhydrophilic and superhydrophobic properties depending on the surface chemistry. These properties were preserved during prolonged storage and resisted moderate mechanical stress. By combining different contact angle and drop impact measurements, the optimum surface design and plasma processing parameters for maximizing stability of the superhydrophobic or superhydrophilic properties of the PET films were identified.

Graphical abstractPET films have been nanostructured at different levels using oxidative plasma treatment and perfluorinated coatings. Stable superhydrophilic and superhydrophobic PET surface were obtained depending on the chemistry and topography at the surface.Figure optionsDownload full-size imageDownload high-quality image (59 K)Download as PowerPoint slideResearch highlights► A facile method to obtain superhydrophobic surfaces. ► Tunable wetting via etching ratio, i.e. nanopattern geometry. ► Quantification of pattern stability via drop-impact studies.