Previously, scientists relied on chemical modification to make surfaces repel liquids, a time-consuming process. In the end, each coating worked to repel only certain liquids, and oil-repellent surfaces simply weren’t possible to manufacture. The new surface blocks almost all liquids. Researchers can also turn off the physical barrier: An electric voltage instantly draws liquids down between each spike, where they spread out along the base upon which the spikes sit. This switchable quality makes the surface perfect for controlling liquids in “lab on a chip” chemical reactors, and its super-repellent properties could help keep helicopter blades free of heavy, altitude-robbing water and ice.
