Fabrication of superhydrophobic and oleophobic Al surfaces by chemical etching and surface fluorination

• Published in: Thin solid films Vol. 585; pp. 76 - 80
• Main Authors: Choi, Hak-Jong, Shin, Ju-Hyeon, Choo, Soyoung, Ryu, Sang-Woo, Kim, Yang-Doo, Lee, Heon
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.06.2015
• Subjects: Aluminum; Chemical etching; Contact angle; Deionization; Diffraction; Etching; Hierarchy; Oleophobicity; Superhydrophobicity; Thin films; X-rays; Oleophobicity; Hierarchy; Superhydrophobicity; Chemical etching; Aluminum
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2015.03.046

Hierarchical Al surfaces were fabricated using three different kinds of alkaline-based chemical etching processes. The surface morphology changes to a needle-like microstructure or to nanoscale flakes on a microscale porous structure depending on the chemical solution used. These surfaces were characterized by field-emission scanning electron microscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy, and contact angle measurements. After the hydrophobic treatment, the etched Al surface shows non-wetting properties, exhibiting a static contact angle over 150° and a dynamic contact angle less than 5° for deionized water. Oleophobic properties for diiodomethane and N,N-dimethylformamide are exhibited by all etched Al surfaces. •This research fabricated and analyzed the etched Al surface via a simple wet etching process.•The morphology of Al surface is changed according to the presence of Zn ions.•The wettability of Al surface is controlled by roughness and surface treatment.•Superhydrophobicity and superoleophobicity are achieved on the wet etched Al mesh.