title: Superhydrophobic surfaces engineered using diatomaceous earth.
abstract: We present a simple method to prepare superhydrophobic surfaces using siliceous exoskeleton of diatoms, a widespread group of algae. This makes diatomaceous earth an accessible and cheap natural material. A micro/nanoscale hierarchical topography was achieved by coating a glass surface with diatomaceous earth, giving rise to a superhydrophilic surface. Superhydrophobic surfaces were obtained by a further surface chemical modification through fluorosilanization. The wettability of the superhydrophobic surface can be modified by Argon plasma treatment in a controlled way by exposure time variation. The chemical surface modification by fluorosilanization and posterior fluorinated SH surface modification by plasma treatment was analyzed by XPS. Using appropriated hollowed masks only specific areas on the surface were exposed to plasma permitting to pattern hydrophilic features with different geometries on the superhydrophobic surface. We showed that the present strategy can be also applied in other substrates, including thermoplastics, enlarging the potential applicability of the resulting surfaces.
authors: 3B's Research Group, Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, Caldas das Taipas, Portugal.
authors: Nuno M
authors: NM
authors: Oliveira
authors: Rui L
authors: RL
authors: Reis
authors: João F
authors: JF
authors: Mano
mesh_terms: D007692:Diatomaceous Earth; D057927:Hydrophobic and Hydrophilic Interactions; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties
chemical_list: D007692:Diatomaceous Earth