Per-fluorinated chemical free robust superhydrophobic copper surface using a scalable technique

Abstract

Robust superhydrophobicity is of immense practical interest in a wide range of applications including self-cleaning, anti-icing, anti-corrosion, atmospheric water harvesting, desalination, condensation, and oil-water separation. However, biohazard associated with the prevalent use of per-fluorinated synthetic chemicals in making these surfaces and the gradual loss of superhydrophobicity have been major roadblocks. Here we develop an environment-friendly and industrially scalable superhydrophobic copper surface using a combination of electrochemical deposition and Lauric acid functionalization. We optimized the synthesis process for ensuring the robustness of these superhydrophobic surfaces. The surface exhibits contact angles as high as 158° with excellent droplet rebounding, self-cleaning, anti-icing, and dropwise condensation abilities. Thermal stability in the range of −15°C to 150°C, mechanical robustness against abrasion, chemical stability under aqueous, acidic, and basic medium, and the excellent plastron layer stability under long-time underwater immersion attest to the high quality of superhydrophobic surfaces for large-scale applications. These coatings when implemented on the curved surface of a copper tube demonstrated appreciable improvement in condensation behavior. Our method provides a sustainable approach for suitable technological interventions in energy and potable water applications requiring robust environment-friendly superhydrophobic surfaces.