Durable and Flexible Hydrophobic Surface with a Micropatterned Composite Metal-Polymer Structure.

Hydrophobic metallic surfaces have attracted much academic and industrial interest due to their promising applications in various fields. Typically, hydrophobicity in metallic materials can be realized by micro/nanostructures and chemical treatment. However, both fragile rough surfaces and low-surface-energy fluorinated silanes are prone to wear and abrasion, leading to the loss of hydrophobicity. In this experiment, we demonstrated a facile and potentially low-cost methodology to fabricate hydrophobic surfaces by integrating a mechanically durable nickel skeleton with an interconnected microwall array filled with hydrophobic poly(tetrafluoroethylene) (PTFE). The interconnected metal frames prevented the removal of the hydrophobic material by abradants, and good hydrophobicity was preserved after more than 1000 cycles of linear abrasion under a local pressure of ∼0.12 MPa. The fabricated surfaces exhibited enhanced anti-icing properties with water droplets compared to unprocessed nickel surfaces. The prepared surfaces also showed superior flexibility. No obvious fracture was observed even after 300 cycles of buckling while the hydrophobic performance was still maintained. The surfaces designed here could provide effective guidance to manufacture large-area surfaces in nickel and other metallic materials that require flexibility, hydrophobic properties, and anti-icing functions for harsh applications.