Facile one-step photopatterning of hierarchical polymer structures for highly transparent, flexible superhydrophobic films

Abstract Superhydrophobic surfaces with mechanical compliance and optical visibility open up new possibilities in practical applications. This work presents a simple, fast, and cost-effective route to fabricate highly flexible and transparent superhydrophobic films with hierarchical surface morphology. Two-tiered polymeric surface structures are readily obtained by a one-step photopatterning approach in conjunction with a roughened sandpaper template. The hierarchical superhydrophobic polymer (HSP) films show excellent wetting properties (static contact angle of >172° and contact angle hysteresis of 84% at 550 nm), and enhanced resistance to water drop impact. In addition, the HSP films exhibit high resistance to repeated bending and pressing deformations (5000 cycles), while stably maintaining their superhydrophobicity. The practical utility of the HSP film is successfully demonstrated through self-cleaning, anti-fogging, and water-jet impact tests.