Watertight: Tom Krupenkin
A trio of prismatic drops (left to right: water, ethylene glycol and ethanol) balances on a new ultra-repellent surface invented by scientists at the University of Wisconsin–Madison. The surface, made up of silicon spikes just 400 nanometers wide, physically repels a wide variety of liquids, including water, oil, solvents and detergents.
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.