Biomimetic 3D-Printed Armored Structures for Durable Superhydrophobic Surfaces: Integrating Macroprotection and Nanofunctionality

Superhydrophobic surfaces, which exhibit exceptional water-repellent properties, are crucial for industrial products and coatings, offering benefits such as maintaining dryness, stain resistance, self-cleaning, frost resistance, and corrosion prevention. However, the micro/nanostructures necessary for superhydrophobicity are typically vulnerable to mechanical stress, easily losing functionality under even slight loads. Here, the study presents an approach to creating highly durable superhydrophobic surfaces using biomimetic 3D printed structures inspired by armadillo armor. By combining protective macrostructures fabricated through low-cost 3D printing with polylactic acid (PLA) filaments, hydrophobic nanoparticles, and a photocurable resin as an interconnecting material, we achieved surfaces that maintain superhydrophobicity even after mechanical wear. Hexagonal structures with varying areas (8–40 mm2) were designed and tested, with larger hexagons (32 and 40 mm2) retaining superhydrophobicity after 100 friction cycles. The liquid–solid contact fraction was identified as a critical factor in determining surface durability. We observed a transition from the Cassie–Baxter to the Wenzel state in intermediate-sized structures, providing insights into superhydrophobicity loss mechanisms. This research demonstrates the potential of integrating 3D printing with nanomaterial surface treatments to create functional, durable superhydrophobic surfaces, offering a scalable, low-cost method for producing wear-resistant coatings suitable for harsh environments.