Fabrication of Biomimetic Micropatterned Surfaces by Sol–Gel Dewetting. Issue 4 (15th January 2019)

• Record Type: Journal Article
• Authors: Colusso, Elena; Martucci, Alessandro; Neto, Chiara
• Is Part Of: Advanced materials interfaces. Volume 6:Issue 4(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-01-15
• Subjects: biomimicry -- dewetting -- micropattern -- sol–gel -- water condensation -- wettability; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.201801629
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Dewetting of thin polymer films has been extensively investigated as a way to generate patterned surfaces. In this paper, the controlled dewetting of sol–gel thin films induced by solvent annealing is reported. The key factors that control the dewetting process are identified and patterns with tunable diameter between 5 and 80 µm and tunable height between 1 and 10 µm are fabricated on a large scale. By changing the chemistry of the sol–gel system, patterns with wetting contrast, consisting of hydrophilic bumps on a hydrophobic layer, are realized. These surfaces are inspired by the exoskeleton of the Namib desert beetle and are amenable to application in atmospheric water capture, as they facilitate condensation and allow for water droplets to roll off at low critical volumes (6–8 µL), similar to the value predicted for the Namib desert beetle. The approach presented is simple, scalable, and can be applied to a wide range of substrates including glass. Transparent micropatterns are realized with high transmittance in the visible range, suitable for fabrication of coatings on windows or microlens arrays. Abstract : This paper reports the fabrication of silicate micropatterns with wettability contrast through dewetting of sol–gel films. The key factors of the dewetting process are investigated and the possibility to fabricate patterns with tunable size is demonstrated. The fabricated surfaces are suited to atmospheric water capture as they facilitate water condensation and easy detachment of water droplets.