Ships could become nearly unsinkable with superhydrophobic tubes

Researchers at the University of Rochester developed a method that etches the inside of aluminum tubes to make them superhydrophobic and trap air, keeping the tubes afloat even when punctured. The team showed connected tubes can form rafts in lab tests and can capture energy from moving water.

Researchers at the University of Rochester's Institute of Optics have reported a new method to make ordinary metal tubes resist water and remain buoyant. The team, led by Chunlei Guo, etched the inside surfaces of aluminum tubes to create microscopic and nanoscale pits that produce a superhydrophobic interior. That textured interior captures and stabilizes a pocket of air that prevents water from filling the tube, and the researchers added an internal divider so the bubble remains trapped even when the tube is pushed vertically. The work builds on earlier superhydrophobic floating devices and aims to improve stability in turbulent conditions. Key findings: - The study, led by Chunlei Guo and published in Advanced Functional Materials, focuses on etching aluminum tube interiors to form micro- and nanoscale pits that make the surface superhydrophobic. - A trapped air pocket inside the treated tubes prevents water ingress and maintains buoyancy; an internal divider helps keep the air bubble in place when oriented vertically. - In laboratory tests the tubes retained buoyancy in rough conditions for weeks and still floated after being punctured many times. - The design offers greater stability than the team’s earlier disk-based devices, which could lose buoyancy at extreme tilts. - Multiple tubes were joined to form rafts in lab experiments with tube lengths approaching half a meter, and those rafts were used to demonstrate capturing energy from moving water. - The project received support from the National Science Foundation, the Bill and Melinda Gates Foundation, and URochester's Goergen Institute for Data Science and Artificial Intelligence. Summary: If scaled, the superhydrophobic tube design could serve as a basis for floating platforms, buoys, or ship components and also has potential for wave-energy capture. The researchers report stable buoyancy in laboratory and rough-condition tests and indicate the approach can be enlarged to support heavier loads. Further scaling and real-world testing are described as aims, but specific deployment timelines are undetermined at this time.