Inspired by the Salvinia effect, we report the fabrication and characterization of a novel “sticky” superhydrophobic surface sustaining a Cassie–Baxter wetting state for water droplets with high contact angles but strong solid–liquid retention. Unlike superhydrophobic surfaces mimicking the lotus or petal effect, whose hydrophobicity and droplet retention are typically regulated by hierarchical micro- and nanostructures made of a homogeneous material with the same surface energy, our superhydrophobic surface merely requires singular microstructures covered with a hydrophobic coating but creatively coupled with hydrophilic tips with different surface energy. Hydrophilic tips are selectively formed by meniscus-confined electrodeposition of a metal (e.g., nickel) layer on top of hydrophobic microstructures. During the electrodeposition process, the superhydrophobic surface retains its plastron so that the electrolyte cannot penetrate into the cavity of hydrophobic microstructures, consequently making the electrochemical reaction between solid and electrolyte occur only on the tip. In contrast to typical superhydrophobic surfaces where droplets are highly mobile, the “sticky” superhydrophobic surface allows a water droplet to have strong local pinning and solid–liquid retention on the hydrophilic tips, which is of great significance in many droplet behaviors such as evaporation.

中文翻译：

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弯月限制电沉积对Salvinia效果的“粘性”超疏水表面的影响

受Salvinia效应的启发，我们报道了一种新颖的“粘性”超疏水表面的制造和表征，该表面保持了Cassie-Baxter润湿状态，具有高接触角但具有很强的固液保持力。与模仿荷花或花瓣效应的超疏水表面不同，超疏水表面的疏水性和液滴保留通常由具有相同表面能的均质材料制成的分级微结构和纳米结构调节，而我们的超疏水表面只需要覆盖有疏水涂层的奇异微结构，但可以创造性地偶联具有不同表面能的亲水性尖端。通过在疏水微结构的顶部上的金属（例如，镍）层的弯月面限制电沉积来选择性地形成亲水性尖端。在电沉积过程中，超疏水表面保留了其plastron，因此电解质无法渗透到疏水微结构的空腔中，因此使固体和电解质之间的电化学反应仅在尖端发生。与液滴具有高流动性的典型超疏水性表面相反，“粘性”超疏水性表面使水滴在亲水性尖端上具有很强的局部钉扎和固液保留能力，这在许多液滴行为（例如蒸发）中具有重要意义。