Superomniphobic surfaces for easy-removals of environmental-related liquids after icing and melting

Superhydrophobic surfaces often lose the easy-removal ability of liquids during icing & melting cycles due to the impalement phenomena of air pockets. Especially for the most common mixed liquids in normal life, their difficult-removals after icing and melting have brought colossal troubles in the fields of aviation, energy, biomedicine, etc. Here we adopt the ultrafast laser to fabricate the optimal micro-nanostructured surfaces, realizing excellent superomniphobicity for seven environmental-related liquids. It is demonstrated that different droplets on the surfaces recover well to the original Cassie-Baxter state after melting, and can be removed easily at low tilted angles. The ice adhesion strengths of the seven liquids as low as 5 kPa and the micro-nanostructure durability ensure the long-term easy-removal after icing. Compared with the ice adhesion strength of untreated surfaces (264.4 ± 17.6 kPa), those of our designed surfaces have decreased by over 50 times. Icing and melting processes are investigated to reveal the easy-removal mechanisms that specifically distributed solutes and bubbles after icing impact downwards significantly to accelerate the recovery of the Cassie–Baxter state during melting. A series of environmental-related durability experiments including continuous icing & melting cycles, long-term salt spray, and high-pressure water jet impact further demonstrate the surfaces promising for real applications.