Superamphiphobic PDMS/silica nanoparticle surfaces with high liquid impact resistance: effect of structural hierarchy on superamphiphobicity

We propose an efficient method for fabricating superamphiphobic surfaces with hierarchical micro/nano-structured morphologies on microhoodoo structures that exhibit high liquid impact resistance. The proposed method combines optical microscopy, photolithography, replica molding, and spray coating of polydimethylsiloxane (PDMS)/silica nanoparticle (SiNP) solutions. We systematically investigate key parameters influencing the water and hexadecane repellency of these surfaces, including (i) the center-to-center distance between PDMS microhoodoo structures, (ii) the PDMS-to-SiNP mixing ratio, and (iii) the spray volume. Notably, optimizing the spray volume within a critical range improves the uniformity of the hierarchical surface texture, stabilizes the Cassie–Baxter state, and facilitates liquid bounce. This innovative approach provides valuable insights into the design of superamphiphobic surfaces, resulting in practical applications such as water- and oil-resistant, self-cleaning, anti-icing, and antifouling surfaces.

Graphical abstract

Efficient fabrication of superamphiphobic surfaces with hierarchical micro/nano-structures on microhoodoo structures, achieved through optical microscopy, photolithography, replica molding, and spray coating of PDMS/SiNP solutions. Key factors influencing liquid repellency—such as microhoodoo spacing, PDMS/SiNP ratio, and spray volume—are systematically explored. Optimizing spray volume enhances surface texture uniformity, stabilizes the Cassie–Baxter state, and promotes liquid bounce, leading to practical applications in self-cleaning, anti-icing, and antifouling surfaces.