University of Texas at Dallas researchers have discovered that a novel surface they developed to harvest water from the air encourages tiny water droplets to move spontaneously into larger droplets.
When researchers placed microdroplets of water on their liquid-lubricant surface, the microdroplets propelled themselves to climb, without external force, into larger droplets along an oily, ramp-shaped meniscus that forms from the lubricant around the larger droplets. The “coarsening droplet phenomenon” formed droplets large enough for harvesting.
“This meniscus-mediated climbing effect enabled rapid coalescence on hydrophilic surfaces and has not been reported before. We have discovered a new physical phenomenon that makes it possible to harvest water more rapidly from air without external force,” said Dr. Xianming Dai
, assistant professor of mechanical engineering
in the Erik Jonsson School of Engineering and Computer Science
, who led the work. “If we don’t have this new phenomenon, the droplets would be too small, and we could hardly collect them.”