An easy-to-implement method for fabricating superhydrophobic surfaces inspired by taro leaf

An easy-to-implement method by which to fabricate superhydrophobic surfaces inspired taro leaf was successfully applied on 316L stainless steel via combining nanosecond laser (NL) processing and spin-coating techniques. The laser-textured surface composed of microscale frameworks and central bumps was fabricated by NL processing based on properly designed biomimetic patterns, and a layer of nanoscale carbon black/polydimethylsiloxane (CB/PDMS) particles was covered on it by spin-coating. The effect of pattern parameters (i.e., the inscribed circle radius of framework and the radius of central bump) on wettability of biomimetic surface was investigated. All as-prepared biomimetic surfaces with micro-nano hierarchical structures showed excellent superhydrophobicity with the water contact angle of ∼155° and contact angle hysteresis of ∼2°. By comparing the untreated surface, the wetting behavior and evaporation mode of the biomimetic surface occurred an obvious transformation. Meanwhile, experiments indicated that the biomimetic surface not only had liquid-repelling and self-cleaning functions, but also maintained remarkable mechanical robustness and superhydrophobic durability. The method is efficient for fabricating biomimetic superhydrophobic surfaces applied to liquid-repelling, evaporation-transforming and self-cleaning fields.