Spray-Induced High Laplace Pressure for Stable Cassie-Baxter Superhydrophobic Anti-Icing Surfaces

Superhydrophobic surfaces (SHSs) are promising for anti-icing applications but often suffer from low-temperature-induced infiltration that destabilizes the Cassie-Baxter state. Here, we present a scalable spray-based engineering strategy to regulate Laplace pressure and enhance wetting stability by tailoring the morphology of ZIF-67 nanofillers inspired by Oxalis corniculate L. Transforming conventional 3D particles into 2D flaky structures induces a loosely packed architecture during spraying, reducing texture spacing and increasing local Laplace pressure (up to 500.3 Pa). This morphology-driven surface design suppresses infiltration and stabilizes the Cassie-Baxter state at low temperatures. The optimized coating achieves a freezing delay time of 514.97 s, a low ice adhesion strength of 25.7 kPa, and improved corrosion resistance. Although its Laplace pressure is lower than that of laser-textured metallic SHSs, the sprayed surface exhibits superior low-temperature contact-angle stability due to hierarchical porosity, reduced interfacial heat transfer, and effective air retention. These findings demonstrate that spray-induced Laplace pressure engineering provides a practical and scalable route toward durable ice-phobic coatings.