WESTWOOD—UCLA engineering professor Chang-Jin “C..J.” Kim and his postdoctoral student, Tingyi “Leo” Liu, have invented a new, “superomniphobic” surface texture that is impervious to all liquids, regardless of what the surface is made of.
Facilitated by cutting edge nanoscale technology, the team of the engineers refined a method of etching flathead nail-shaped patterns into a surface, thereby causing it to repel all types of liquids. Each nail is a fraction of the width of a human hair, at just 20 micrometers wide.
This pattern can be practically applied to glass, metal or plastic, making those surfaces impermeable by all types of liquids, and preventing corrosion.
It works because the nanoscale pattern detail makes liquid hold together as a sphere.
While other “hydrophobic” material exist, like nonstick cookware, which causes water to “bead up and roll around effortlessly,” those materials are not “oleophobic,” which means they do not repel oil-based liquids.
Until now, a true “omniphobic” surface, that is, a surface that repels all liquids without exception, has eluded scientists. This new surface does not utilize a chemical-composition to repel liquid (like nonstick cookware does), but it rather relies solely on the physical texture of the pattern.
Professor Kim told Canyon News, “We broke [the] barrier and developed surfaces that strongly repel (i.e. super-repel”) all liquids including fluorinated solvents. Another interesting aspect of our finding is for the superomniphobic surface, it does not really matter whether the material itself is repellent to the liquid or not.”
Speaking about the UCLA community, Kim said, “We have outstanding students here at UCLA and it’s great to teach and work with them in creating new technologies, like our new surfaces, that down the road, could be of great benefit to society.”
“Our superomniphobic surface is made of pure silica,” he said, “on which even water wets perfectly. Yet, when textured properly, the surface super-repels all liquids. This unique nature is expected to bring new possibilities for industrial, land, and medical applications.”
The pattern is also thought to be resilient to UV-light and high temperatures. Consequently, it may be helpful, for example, when applied to bridges, to prevent rusting, or to cars, to counteract paint fading.
Another potential application for this discovery could be on biomedical devises “because its repelling properties would not degrade because of fouling by biofluids.”
