Superhydrophobic ultra-high molecular weight polyethylene porous material with self-cleaning ability, long-term stability, and high durability

Capillary-Driven Water Transport by Contrast Wettability-Based Durable Surfaces

“…The beetle basks in the fog, standing upside down on top of sand dunes: water first collects in small droplets, which then roll down the beetle’s back toward its mouth, under gravity . Inspired by this and other examples, it is possible to create contrast wettability surfaces for many engineering applications where the directional transport of liquids is required. − To achieve such contrast with wettable surfaces, various techniques based on wet chemistry and dry etching have been proposed, − followed by surface modifications. − Notwithstanding the plethora of techniques available, such approaches did not lead to commercial products due to mainly two reasons: first, durability issues in real-world applications − and, second, production upscaling concerns related to the use of chemicals or processes that are not environmentally friendly (according to REACH, RoHS list, and other environmental regulations). , To overcome these shortcomings, in the present study, we present a biomimetic design based on contrast wettability to control water transport on aluminum alloy, one of the most common engineering substrates used in industry; this can be applied in applications where guided water transport is essential, such as proton exchange membrane fuel cells, digital microfluidics, thermal management of electronics, and water harvesting applications. − ,, The novel surface structure, fabricated by applying a durable powder coating of a fluorine-based polymer to anodized aluminum followed by a microtexturing technique by a scalable femtosecond laser system, ,,− leverages open capillary-driven water transport: the combination of microscale surface wettability laser textures with millimeter-precise radial tracks enables a self-propelled capillary-driven water transport mechanism. Such an approach allows the fabrication of durable and environmentally friendly surfaces, as validated in both laboratory-based artificial tests and one-year-long natural weathering in Miami, Florida, USA, a location with 4 times more aggressive weathering conditions than in Europe, which is a crucial factor for extensive evaluation studies before using it on production scale.…”