Fogging occurs when moisture condensation takes the form of accumulated droplets with diameters larger than 190 nm or half of the shortest wavelength (380 nm) of visible light. This problem may be effectively addressed by changing the affinity of a material's surface for water, which can be accomplished via two approaches: i) the superhydrophilic approach, with a water contact angle (CA) less than 5°, and ii) the superhydrophobic approach, with a water CA greater than 150°, and extremely low CA hysteresis.[1] To date, all techniques reported belong to the former category, as they are intended for applications in optical transparent coatings. [1][2][3][4][5][6][7] A well-known example is the use of photocatalytic TiO 2 nanoparticle coatings that become superhydrophilic under UV irradiation. [3,4] Very recently, a capillary effect was skillfully adopted to achieve superhydrophilic properties by constructing 3D nanoporous structures from layer-by-layer assembled nanoparticles. [1,5,6] The key to these two "wet"-style antifogging strategies is for micrometer-sized fog drops to rapidly spread into a uniform thin film, which can prevent light scattering and reflection from nucleated droplets. Optical transparency is not an intrinsic property of antifogging coatings even though recently developed antifogging coatings are almost transparent, and the transparency could be achieved by further tuning the nanoparticle size and film thickness. To our knowledge, the antifogging coatings may also be applied to many fields that do not require optical transparency, [7] including, for example, paints for inhibiting swelling and peeling issues and metal surfaces for preventing corrosion. These types of issues, which are caused by adsorption of moisture, are hard to solve by the superhydrophilic approach because of its inherently "wet" nature. Thus, a "dry"-style antifogging strategy, which consists of a novel superhydrophobic technique that can prevent moisture or microscale fog drops from nucleating on a surface, is desired. Recent bionic researches have revealed that the self-cleaning ability of lotus leaves [8][9][10] and the striking ability of a water-strider's legs to walk on water [11] can be attributed to the ideal superhydrophobicity of their surfaces, induced by special micro-and nanostructures. To date, the biomimetic fabrication of superhydrophobic micro-and/or nanostructures has attracted considerable interest, [12][13][14][15][16][17] and these types of materials can be used for such applications as self-cleaning coatings and stain-resistant textiles. Although a superhydrophobic technique inspired by lotus leaves is expected to be able to solve such fogging problems because the water droplets can not remain on the surface, [1] there are no reports of such antifogging coatings. Very recently, researchers from General Motors have reported that the surfaces of lotus leaves become wet with moisture because the size of the fog drops are at the microscale-so small that they can be easily trapped in the interspaces among mic...

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