Photothermal superhydrophobic surface with good corrosion resistance, anti-/de-icing property and mechanical robustness fabricated via multiple-pulse laser ablation

Corrosion and ice accumulation occurring on carbon steel bring about huge economy lost, resource waste, and even hazard event. Fabricating black superhydrophobic surfaces is an effective method for improving the anti-corrosion and anti-/de-icing properties of metallic materials. However, it is still a challengeable task to fabricate a robust black superhydrophobic surface on carbon steel through an eco-friendly method. Herein, a black superhydrophobic surface was obtained on 45 steel substrate via a simple and fluorine-free method, i.e., multiple-pulse laser ablation followed by chemical modification with hexadecyltrimethoxysilane (HDTMS). The obtained surface exhibits a water contact angle of 156° and possesses a low reflectance (<9%) in the wavelength range of 400 ∼ 2500 nm. The surface displays an excellent photothermal property with a temperature rise of 52 °C under 1 sun of illumination within 8 min. Electrochemistry data reveals that the surface has good corrosion resistance with 64.78-times lower corrosion current density and 73.81-times higher charge transfer resistance than the steel substrate. Anti-icing test shows that the surface possesses 2547 s longer freezing delay time and at least ∼ 3 times lower de-icing force than the steel substrate, and photothermal de-icing test demonstrates that the ice on the surfaces starts thawing within 60 s under 0.5 sun of illumination, indicating that the surface has excellent anti-/de-icing property. Moreover, after impacting by 2000 g of sands or 400 times of tape peeling tests, the surface still maintains superhydrophobicity, indicating the good mechanical robustness of the surface.