The fine nanostructure on the cicada wing of Cryptotympana atrata fabricius, which exhibits hydrophobicity and antireflectivity, is carefully examined. A promising strategy is proposed for facilely and successively replicating the natural functional nanostructure of the cicada wing onto polystyrene (PS) surfaces. First, a nickel replica with tapered nanopores is fabricated by combining electroless plating and subsequent electroplating with the natural cicada wing as an original template. Then, using microinjection compression molding, with the nickel replica as a template, the tapered nanopores are transcribed onto the PS surface, resulting in orderly and densely arranged nanopillars with a mean diameter of about 156 nm and a mean pitch of about 180 nm. The natural cicada wing and fabricated nickel replica are reusable. Interestingly, the PS replica surface exhibits a water contact angle of 143° ± 2° and a reflectance of about 4% in the wavelength range of 400-1000 nm. These results mean that the bionic PS replica not only inherits the nanostructure of the natural wing, but also its hydrophobic and antireflective properties. The mechanisms for the hydrophobic and antireflective properties are revealed via composite wetting interface and effective medium layer on the replica surface, respectively. The proposed fast and efficient replication strategy can be an excellent candidate for mimicking bio-inspired functional micro/nanostructures without complicated procedures and expensive materials.

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Solar evaporation is one of the most attractive and sustainable approaches to address worldwide freshwater scarcity. Unfortunately, it is still a crucial challenge that needs to be confronted when the solar evaporator faces harsh application environments. Herein, a promising polymer molding method that combines melt blending and compression molding, namely micro extrusion compression molding, is proposed for the cost‐effective fabrication of lightweight polyethylene/graphene nanosheets (PE/GNs) foam with interconnected vapor escape channels and surface micro‐nanostructures. A contact angle of 155 ± 2°, a rolling angle of 5 ± 1° and reflectance of ≈1.6% in the wavelength range of 300–2500 nm appears on the micro‐nanostructured PE/GNs foam surface. More interestingly, the micro‐nanostructured PE/GNs foam surface can maintain a robust superhydrophobic state under dynamic impacting, high temperature and acid‐/alkali solutions. These results mean that the micro‐nanostructured PE/GNs foam surface possesses self‐cleaning, anti‐icing and photothermal deicing properties at the same time. Importantly, the foam exhibits an evaporation rate of 1.83 kg m−2 h−1 under 1 Sun illumination and excellent salt rejecting performance when it is used as a self‐floating solar evaporator. The proposed method provides an ideal and industrialized approach for the mass production of solar evaporators suitable for practical application environments.