Bioinspired\nHierarchical\nT Structures for Tunable\nWettability and Droplet Manipulation by Facile and Scalable Nanoimprinting

Developing\nsurfaces that effectively repel low-surface-tension\nliquids with tunable adhesive properties remains a pivotal challenge.\nMicronano hierarchical re-entrant structures emerge as a promising\nsolution, offering a robust structural defense against liquid penetration,\nminimizing area fraction, and creating narrow gaps that generate substantial\nupward Laplace pressure. However, the absence of an efficient, scalable,\nand tunable construction method has impeded their widespread applications.\nHere, drawing inspiration from springtail epidermal structures, octopus\nsuckers, and rose petals, we present a scalable manufacturing strategy\nfor artificial micronano hierarchical T-shaped structures. This strategy\nemploys double-transfer UV-curing nanoimprint lithography to form\nnanostructures on microstructured surfaces, offering high structural\ntunability. This approach enables precise control over topography,\nfeature size, and arrangement of nano- and microscale sections, resulting\nin superamphiphobic surfaces that exhibit high contact angles (>150°)\nand tunable adhesive forces for low-surface-energy liquids. These\nsurfaces can be applied to droplet-based microreactors, programmable\ndroplet-transfer systems, and self-cleaning surfaces suitable for\nvarious liquids, particularly those with low surface tension. Remarkably,\nwe have also succeeded in fabricating the hierarchical structures\non flexible and transparent substrates. We demonstrate the advantages\nof this strategy in the fabrication of hierarchical micronanostructures,\nopening up a wide range of potential applications.