Geometry‐Enabled Recoverable Floating Superhydrophobic Metallic Tubes

ABSTRACT Biomimetic water‐repellent superhydrophobic (SH) self‐floating devices have promised a wide range of applications. However, current SH floaters are usually only capable of being used in small‐sized devices due to their lack of mechanical strength and resistance to environmental stress, making them prone to damage. In this work, we demonstrate a metallic SH tube with a reliable underwater buoyancy, high adaptability to violent environments, and strong resistance to mechanical abrasion and structural damage. The remarkable floating ability comes from stable air trapped inside the tube. Besides being able to float back to the surface even after being fully forced into water, the SH tube can also maintain buoyancy under severe tilting, water impact, and even under severe structural damage. The SH tubes assembly can be used to construct large vessels, watercrafts, floating platforms, and buoys for marine applications. As an example, we demonstrate a floating SH electrical energy generator to harvest ocean tidal energy.