Article ID Journal Published Year Pages File Type
1490311 Materials Research Bulletin 2011 6 Pages PDF
Abstract

This work reports the fabrication of diverse nanostructured alumina films under high-field anodization in oxalic-acid electrolytes. Different surface morphologies of these alumina films can be obtained by adjusting reaction parameters, which was ascribed to the anisotropic chemical etching induced by the reaction heat and the concentration gradient of the oxalic-acid solution along the nanopore channels during the high-field anodization process. These alumina surfaces without coating low energy materials show remarkable morphology-dependent wettability. Specially, the alumina surface consisting of porous underlayer and nanowire pyramids with no chemical modification reveals excellent super water-repellent behavior for the first time. This study could provide a new approach for designing functional surfaces with tunable wettability.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Dynamic evolution of alumina surface morphologies was revealed. ► Heat-driven dissolution with anisotropic etching model was proposed. ► The unmodified alumina surfaces showed remarkable morphology-dependent wettability. ► Super water-repellent alumina surfaces without modification was firstly reported.

Related Topics
Physical Sciences and Engineering Materials Science Ceramics and Composites
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