Three-dimensional self-similar super-repellent films for underwater display and switching wettability
Given that the intrinsic sensitivity toward harsh settings and new requirements in emerging fields, the development of bio-inspired material, particularly super-repellent material, has been severely restricted in many practical scenarios. In this work, a robust self-similar super-repellent film (SSF) with pattern manipulation and erasion healing for underwater display and switching wettability was successfully fabricated via a facile bulk-deposition method. The strategic integration of covalently cross-linked network with hierarchical topography through solidification and dehydroxylation commendably conferred extreme super-hydrophobicity on the SSF. Thanks to the presence of three dimensional super-hydrophobicity and regenerative characteristic, the SSF was repeatedly realized the switching wettability (>5 times) between super-hydrophobic and super-hydrophilic states by means of erasion healing approach. More importantly, the novel combination of pattern manipulation and light-reflective phenomenon enabled the SSF to successfully achieve underwater display with the employment of flash light. Furthermore, the embedded bio-inspired wettability on the SSF remained unaltered after being subjected to various severe physical settings (>60 times), highly corrosive phase (pH 1-14), boiling/ice water and outdoor experiment. Our findings convincingly stand out as a new tool to advance the synthesis of robust and versatile super-repellent materials for various promising applications.