A hydrophilic directional slippery rough surface outperforms conventional liquid-repellent surfaces in water harvesting.

The benefits of being repellent: The accumulation of foreign substances on a surface, whether it is dirt on a window or ice on an airplane wing, can lead to hazardous conditions. Many surfaces have been engineered to resist the accumulation of one type of fluid or matter in a particular state, but engineering broader resistivity has remained a challenge. For example, surfaces that repel water droplets may still be susceptible to fog accumulation. Dhyani et al. review the wetting performance and fouling resistance of different liquid-repellent coatings, focusing on superhydrophobic, superomniphobic, lubricant-infused, and liquid-like surfaces. Two key aspects are the performance of the surface to different foulants and the relevance of considering different length scales. Science , aba5010, this issue p. eaba5010

Since the early discovery of the antireflection properties of insect compound eyes, new examples of natural antireflective coatings have been rare. Here, we report the fabrication and optical characterization of a biologically inspired antireflective surface that emulates the intricate surface architectures of leafhopper-produced brochosomes—soccer ball-like microscale granules with nanoscale indentations. Our method utilizes double-layer colloidal crystal templates in conjunction with site-specific electrochemical growth to create these structures, and is compatible with various materials including metals, metal oxides, and conductive polymers. These brochosome coatings (BCs) can be designed to exhibit strong omnidirectional antireflective performance of wavelengths from 250 to 2000 nm, comparable to the state-of-the-art antireflective coatings. Our results provide evidence for the use of brochosomes as a camouflage coating against predators of leafhoppers or their eggs. The discovery of the antireflective function of BCs may find applications in solar energy harvesting, imaging, and sensing devices.