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Inspired by “Lotus effect” and “Petal effect” from nature, superhydrophobic materials have become a hot spot in recent years. However, the researches on these materials still face great challenges. Herein, the superhydrophobic material with transition between “Lotus effect” and “Petal effect” is fabricated via a facile strategy. In the preparation, the organosilicon polymer acts as the matrix, while modified nano-CaCO₃ (M-CaCO${}_3)$ and hydrophobic nano-SiO₂ (H-SiO${}_2)$ act as the dispersed phase, to construct the superhydrophobic material (OSiP–Ca–Si). Through regulating the ratio of M-CaCO₃ and H-SiO₂, the wetting properties of materials can be controlled for the transition between “Lotus effect” and “Petal effect”. For the materials with different effects, both of the water contact angles (WCAs) are above $150^{\circ }$C, while the slide angles (SAs) are $4^{\circ }$C and $180^{\circ }$C, respectively. The transition mechanism can be explained by the distinct microstructures and the roughness they caused due to the different compositions. It is demonstrated that the material with “Lotus effect” possesses an outstanding self-cleaning function, and the material with “Petal effect” can well be applied in water harvesting. Therefore, this work provides a facile strategy for designing the superhydrophobic material with transition between “Lotus effect” and “Petal effect”, and endows them with different applications, thus exhibiting great significance in the advancement of superhydrophobic materials.

ZnO films with hierarchical structures were prepared in an aqueous solution of zinc nitrate, hexamethylenetetramine and hydrofluoric acid. They demonstrated superhydrophobicity and two superhydrophobic states conversion from sticky to slippy after they were modified by fluoroalkylsilane (FAS) self-assemble layers. Before FAS modification, ZnO hierarchical structures, having sphere-like microstructures with nano-petals, showed water contact angle of 151° and a sticky behavior: water droplets rest on such surface did not slide when the surface was tilted to any angle or even upside down, indicating a strong adhesion between water and the surface. However, after FAS modification, ZnO films showed an increase of water contact angle up to 164° and a large difference in dynamic wetting properties: water droplets moved spontaneously and hardly came to rest even on a horizontal surface. The transition from sticky ("Wenzel's state") to slippy ("Cassie's state") resulted from surface free energy change from high to low. The results also confirm that the low enough surface energy, cooperating with surface roughness, is crucial in making Cassie's state superhydrophobicity. The realization of conversion from sticky to slippy is of importance for further understanding wetting properties and applications of ZnO micronanostructures.