Development of superhydrophobic metallic surfaces with tuned morphology through microwave processing

• Published in: Materials chemistry and physics 2022-01, Vol.275, p.125310, Article 125310
• Main Authors: Ivvala, Jayanth, Arora, H.S., Grewal, H.S.
• Format: Article
• Language: English
• Subjects: Adhesion; Aluminum base alloys; Functional; Hydrophobic surfaces; Hydrophobicity; Hydrothermal treatment; Hysteresis; Metals and alloys; Morphology; Nanostructures; Superhydrophobicity; Surfaces; Wetting
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2021.125310

The present study utilized microwave-based hydrothermal treatment to develop a durable superhydrophobic aluminium alloy (AA5083). The surface morphology was effectively tuned through modulation in processing temperatures with the transition from nanofibrils (NF) to densely networked flake-like (DNF) structures. Subsequently, the microwave processed sample surfaces (AA5083) were grafted with precursors of a silanizing agent (1H, 1H, 2H, 2H-Perfluorooctyltriethoxysilane). The silanization of nanostructured surfaces imparted superhydrophobicity (θs>160°), with low hysteresis (10°) combined with low de-wetting resistance (θt∼40°) indicated metastable Cassie state for NFs owing to reduced longitudinal pinning and three-phase line sagging. As a result of the densely packed structures, the DNFs ensure low adhesion and hysteresis because of enhanced Laplace pressure. The mechanically stable DNFs showed high resilience to dynamic and impact loadings. Thus, microwave processing is a viable and efficient means of generating durable nanostructures for developing metallic superhydrophobic surfaces. [Display omitted] •Facile microwave processing was utilized to develop superhydrophobic aluminum alloy.•Distinct surface morphologies generated through altering microwave power.•Highly dense nanoflake morphological surfaces exhibit a stable Cassie state.•The influence of liquid surface tension on wetting, and adhesion was explored.•Nano flakes showed high wetting and mechanical stability than nano-fibrils.