It’s been more than 8 years since researchers found a way to alter a surface so that water would crawl uphill. Now, expanding on that work, they have made individual water drops race across flat, level surfaces at a brisk clip of 3 miles per hour.
Payoffs of the new capability could include improved industrial coatings, printing processes, and cooling technologies, comments Darsh T. Wasan of the Illinois Institute of Technology in Chicago. A water-moving coating might whisk away liquid, rather than simply repel it as ordinary waterproofing does, adds Manoj K. Chaudhury of Lehigh University in Bethlehem, Pa., whose team reported its results in the Jan. 26 Science.