Print-on-demand biomimetic particles enable robust superhydrophobic surfaces with programmable wettability

Hydroxyl-rich biomimetic particles are synthesized for bionic lotus/petal microstructures construction. • Direct-write printing of interchangeable inks creates superhydrophobic surfaces with programmable wettability • Interparticle hydrogen-bonding network and interfacial covalent bonds ensure mechanical durability. • The prepared surface enables applications such as liquid manipulation, anti−/de-icing, and patterning. Functional surfaces with controlled wettability are in high demand across fields. However, achieving such a surface property flexibly while ensuring its durability remains challenging. Here, inspired by natural organisms, we construct two types of biomimetic microstructures on target substrates, achieving low-adhesion (lotus effect) and high-adhesion (petal effect) superhydrophobic surfaces, respectively. Both microstructures are direct-write printed from dual-roughness biomimetic particles (BPs) and alkyl ketone dimer (AKD). The printing sequence determines their distinct wetting properties. The surface displays the lotus effect when AKD forms the outer layer (contact angle = 159.2°, sliding angle = 5.2°), granting it self-cleaning and anti-icing performance. The surface can resist scratching, peeling, and hundreds of severe abrasion cycles, which benefits from the high interfacial strength generated by the synergistic effect between the pre-formed interlinked network of BPs and the esterification with AKD. Crucially, when BPs are positioned on the outer layer, the surface switches to petal effect, where droplets remain pinned without sliding or falling off even when the surface is inverted (180°). By programming the printing path, this strategy is proven to exhibit significant promise in on-demand patterning and liquid manipulation. Download: Download high-res image (142KB) Download: Download full-size image