Biomimetic 3D-Printed Salvinia molesta Surfaces for Geometry-Driven Wetting Control

Area of Science:

• Materials Science
• Surface Science
• Bioinspired Engineering

Background:

• Functional bioinspired surfaces are crucial for applications like water repellency and drag reduction.
• The Salvinia effect offers a model for water-repellent surfaces, but its complex geometry hinders artificial replication.
• Traditional methods for fabricating such surfaces are limited by complexity and processing steps.

Purpose of the Study:

• To demonstrate the fabrication of Salvinia-inspired microstructured surfaces using two-photon polymerization (2PP).
• To investigate geometry-driven wetting phenomena in a monomaterial system using these fabricated surfaces.
• To explore the potential of 2PP in creating advanced functional surfaces with tunable wetting properties.

Main Methods:

• Utilized two-photon polymerization (2PP) for high-resolution fabrication of microstructures.
• Designed and printed base trichome geometries with varying print profiles.
• Created apex-modified designs to study geometry-driven pinning effects within the same printed material.

Main Results:

• Achieved apparent static contact angles exceeding 135°, indicating significant water repellency.
• Demonstrated a meniscus retention distance of 0.47 mm, showcasing robust wetting control.
• Successfully decoupled the apparent wetting behavior from the intrinsic hydrophilicity of the printed material.

Conclusions:

• Two-photon polymerization (2PP) is a viable method for fabricating complex bioinspired microstructures.
• The study highlights the critical role of surface geometry in controlling wetting behavior.
• 2PP enables the creation of advanced water-repellent surfaces independent of inherent material hydrophobicity.