Cross-scale interface engineering strategy to achieve self-healing antifouling material strength and toughness symbiosis

•A composite coating with in-situ Zn-MOF and multiple dynamic bonds was fabricated through the cross-scale interface engineering strategy.•The coating possessed enhanced strength and toughness utilizing the strategy.•The coating exhibited improved self-healing and antifouling performance applying the strategy. The incorporation of self-healing technology into antifouling coatings is crucial for the extension of their service life and durability. However, the challenge lies in the insufficient coexistence of strength and toughness hinders their long-term serviceability. Here, this study proposes a cross-scale interfacial engineering strategy for self-healing antifouling coatings inspired by the multiscale microstructure of natural biomaterials The strategy involves the in-situ growth of antifouling zinc-based metal–organic frameworks (Zn-MOF) within a self-healing polymer network constructed by multiple hydrogen bonds. The synergistic cross-scale interfacial interactions between Zn-MOF and the polymer molecules, combined with the intrinsic antifouling properties of Zn-MOF, significantly enhance the strength, toughness to 27.48 MPa, 277.81 MJ/m3, and benefit improving antifouling performance. Moreover, the molecular integration of Zn2+-pyridine coordination optimizes the microphase structure of the polymer matrix and embeds the advantage of its fast damage response, thereby further enhancing the robustness, and reaching self-healing efficiency to 91.74 % at 40 °C for 24 h. Overall, the proposed strategy represents a viable approach for the fabrication of highly resilient and tough self-healing antifouling coatings.