Employing micro pyramidal holes and porous nanostructures for enhancing the durability of lubricant-infused surfaces in anti-icing

Abstract Slippery liquid-infused porous surfaces (SLIPSs) have drawn tremendous attentions due to their excellent self-cleaning and anti-icing properties, where durability becomes one of most concerned issues. Here, we demonstrate a robust lubricant-infused surface with enhanced durability by introducing micro pyramidal holes and porous nanostructures. The porous nanostructures serve to retain the lubricant whilst the robust micro pyramidal holes provide protection for the nanostructures. SLIPSs with micro pyramidal holes (P-SLIPSs) are achieved via anisotropic etching and spraying superhydrophobic coatings. The sliding angle of P-SLIPS is as low as 1.5°, enabling liquid droplets including ink, milk and glycerol to slide easily on the surface. The ice adhesion strength of the P-SLIPS is about 11.5 kPa, similar to that of the nanostructured SLIPS without micro pyramidal holes but much lower than that of glass, Al alloy, silicon and superhydrophobic surfaces. After 20 icing/deicing cycles, the ice adhesion strength of the P-SLIPS is significantly lower than that of the nanostructured SLIPS. This is mainly attributed to the introduction of the robust micro pyramidal holes, which can protect the nanostructures from damaging during the icing/deicing process. Our work provides a feasible approach to fabricate robust lubricant-infused surfaces with excellent durability for anti-icing and self-cleaning.