Structural Self‐Healing Superhydrophobic Surfaces: Healing Mechanisms, Methods, and Future Challenges

ABSTRACT Superhydrophobic surfaces have important application prospects and value in industry and daily life. However, the practical application of superhydrophobic surfaces is severely hindered by their poor durability. Endowing artificial superhydrophobic surfaces with self‐healing ability has become a key development direction for prolonging their service life. According to the fabrication principles of superhydrophobic surfaces, the repair of superhydrophobicity can be achieved through the migration of low‐surface‐energy substances or the reconstruction of hierarchical micro/nanostructures. While the repair of both chemical compositions and micro/nanostructures is equally important for regaining superhydrophobicity, restoring the structures is significantly more difficult. Moreover, current research focuses more on the restoration of surface chemical compositions rather than micro/nanostructures. This review systematically summarizes the recent development in structurally self‐healing superhydrophobic surfaces, mainly including the biomimetic dynamic repair mechanisms and stimuli‐responsive repair approaches for superhydrophobic micro/nanostructures. The recovery mechanisms of surface micro/nanostructures are mainly based on particle reconstruction, polymer swelling effect, elastic recovery behavior, shape‐memory effect, phase‐change property, and reversible dynamic bonds. Various stimuli‐responsive repair approaches (e.g., heat‐, light‐, electricity‐, or solvent‐induced, and autonomous repair) for superhydrophobic micro/nanostructures are introduced sequentially. Finally, the challenges and future prospects of structurally self‐healing superhydrophobic surfaces are discussed.