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

Controlling watertransport and management is crucial for continuousand reliable system operation in harsh weather conditions. Passivestrategies based on nonwetting surfaces are desirable, but so far,the implementation of superhydrophobic coatings into real-world applicationshas been limited by durability issues and, in some cases, lack ofcompliance with environmental regulations. Inspired by surface patterningobserved on living organisms, in this study we have developed durablesurfaces based on contrast wettability for capillary-driven watertransport and management. The surface fabrication process combinesa hydrophobic coating with hard-anodized aluminum patterning, usinga scalable femtosecond laser microtexturing technique. The concepttargets heavy-duty engineering applications; particularly in aggressiveweather conditions where corrosion is prevalent and typically theanodic aluminum oxide-based coating is used to protect the surfacefrom corrosion, the concept has been validated on anodic aluminumoxide coated aluminum alloy substrates. Such substrates with contrastwettable characteristics show long-term durability in both naturaland lab-based artificial UV and corrosion tests where superhydrophobiccoatings tend to degrade.

Automated summary

Controlling water transport and management in harsh weather conditions is crucial. However, the implementation of superhydrophobic coatings in real-world applications has been limited by durability issues and environmental regulations. In this study, durable surfaces based on contrast wettability were developed using a combination of hydrophobic coating and laser microtexturing. The concept has been validated on aluminum alloy substrates with anodic aluminum oxide coating, showing long-term durability in UV and corrosion tests.