In this article, we demonstrate a simple and cost-effective approach to fabricate antireflective polymer coatings. The antireflective surfaces have 3D structures that mimick moth compound eyes. The fabrication is easily performed via a one-step imprinting process. The 3D arrays exhibit better antireflective performance than 2D arrays over most wavelengths from 400 to 2400 nm. The reflectivity of the 3D arrays is lower than 5.7% over the all of the wavelengths, and the minimum reflectivity is 0.27% at a wavelength of around 1000 nm.

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Superhydrophobic–hydrophilic hybrid surfaces have attracted intensive interest because of their significant academic and commercial values. However, almost all reported microdomain hydrophilicization methods rely on costly micropatterning techniques that need special instruments. Here, we report a microdrop-assisted method for microdomain hydrophilicization of a low-adhesive superhydrophobic surface and demonstrate its utility in high-efficiency nucleation and self-removal of condensate microdrops. Micrometer-sized fogdrops containing polyvinyl alcohol molecules can be selectively captured by breath figures of superhydrophobic surfaces with specific sizes and spatial distributions and can be converted into desired hydrophilic microdomains after thermal evaporation. After exploring the influence of hydrophilic microdomains’ distributions and sizes to surface wettability, adhesion, and condensation dynamics, we achieved an optimal hybrid surface, which possesses 240% average microdrop density, 387% microdrop self-removal rate, and 75% average microdrop diameter as compared to the contrast superhydrophobic surface with uniform chemistry nature. This method is dispensed with special equipment, easy to implement, very cheap, and eco-friendly, which would help develop other superhydrophobic–hydrophilic hybrid surfaces with different functions such as water harvesting, dehumidification, and heat exchange.

Manipulating condensate nucleation, growth, coalescence, and self-removal via bionic super-wettability surfaces has attracted intensive interest because of their significance in fundamental research and technological innovations, for example, water harvesting, power generation, air conditioning, and thermal management. However, it is still a challenge to simultaneously realize confined growth, coalescence, and self-ejection of condensate microdrops, which has not been reported to date. Here, we propose and demonstrate a type of new and more efficient coalescence/self-removal method based on spatially confined growth/coalescence/self-ejection of condensate microdrops, which can be realized using a rationally designed superhydrophobic surface with spatially heterogeneously patterned superhydrophilic microdots (SMDs). Exemplified by superhydrophobic closely packed zinc oxide nanoneedles with SMD patterns, we investigate how the geometric parameters of SMD patterns be designed to simultaneously realize the spatially confined growth/coalescence/self-ejection of patterned microdrops, which are rationalized via theoretical analyses.