Underwater Self‐Healing Solid Slippery Surface with Ultrastable Anti‐Scaling Performance

Abstract Scaling activities pose gigantic challenge for underwater equipments, making the development of surfaces with long‐term anti‐scaling functionality crucial. However, the reduction in anti‐scaling performance caused by the loss of air film limits the application of conventional bionic superhydrophobic surfaces underwater. Here, a novel solid slippery surface (SOSLS) is engineered through the strategic integration of carbon nanotubes (CNTs) as a structural reinforcement matrix and paraffin as a phase‐change filler within a polyurethane (PU) host. The SOSLS demonstrates exceptional anti‐scaling performance, as evidenced by performing 240‐day static and 30‐day dynamic scaling tests. Conversely, the superhydrophobic surface (SHS) develops scaling in the short term and shows obvious scaling at 120 days due to the loss of gas film. Additionally, the SOSLS displays self‐healing ability both in air and underwater at different temperature due to solid‐liquid transition of paraffin and reversible dynamic bonds of PU. Meanwhile, the hydrophobic groups of PU and paraffin act as barriers to separate water molecules from SOSLS. This self‐healing capability further improves long‐term anti‐scaling performance of SOSLS underwater, thereby effectively sustaining service life of SOSLS. Furthermore, the SOSLS exhibits remarkable stability, self‐cleaning and anti‐friction properties. Hence, this SOSLS holds promising prospect for relevant real‐world anti‐scaling applicability.