Microstructure induced nanoparticle composite colloidal film forming coupled hydrophobic liquid delayed icing/frost properties

To enhance the performance of stainless steel materials in low temperature environments, a bioinspired hydrophobic surface with synergistic delayed icing/frosting properties was developed, mimicking the microstructural and chemical characteristics of natural surfaces exhibiting exceptional hydrophobicity and ice resistance. Advanced laser processing technology fabricated a precisely engineered polygonal microarray structure on stainless steel substrates. Subsequently, a nanocomposite colloidal was formulated, consisting of a TiO₂ polyurethane hybrid bonding colloid and CB-SiO₂ hybrid adhesive solution. These functional materials uniformly deposited onto the structured surface via spray coating, forming a robust, bond stabilized super liquid repellent coating with outstanding delayed icing/frosting performance. The experimental results demonstrate that the L-CB@SiO₂ SHCS exhibits superhydrophobic properties, with a static contact angle reaching up to 154.2° and a sliding angle less than 5°. Under cryogenic conditions (−10 °C and −15 °C), the surface significantly delayed ice nucleation by 6824 s and 1715 s, respectively. Moreover, the coating maintained excellent icephobicity, with water droplets completely shedding after 30 impact cycles without ice residue. Even after prolonged exposure 60 min, only a minimal frost layer formed. To elucidate the mechanistic basis of the composite colloidal film's superior anti-icing performance, comprehensive material characterization performed using XRD, FTIR and XPS. Furthermore, the coating durability rigorously assessed through sandpaper rubbing, ethanol hydrolysis, grit falling, and icing-melting cycle tests. The development of such advanced anti-icing stainless steel surfaces holds significant practical implications, as it can substantially reduce de-icing maintenance costs while extending the operational lifespan of cryogenic equipment.