Super Waterproof Materials Cause Water to Bounce like a Ball on Hydrophobic Surfaces

Can you imagine a droplet of water bouncing and rolling like a ball? This behavior may be unusual for water, but it's not impossible-especially when you throw hydrophobic surfaces into the mix. Scientists have created a super-hydrophobic material that's so repellent, it causes water to almost act like a solid.

Super-hydrophobic surfaces have a plethora of applications. They could be used to keep shoes dry or prevent oil from building up on bolts. They could even be used to keep solar panels from getting dirty or creating airplane wings that can resist wingtip icing in cold, humid conditions.

"Our research is geared toward helping to create the idea super-hydrophobic surface," said Julie Crockett, one of the researchers, in a news release. "By characterizing the specific properties of these different surfaces, we can better pinpoint which types of surfaces are most advantageous for each application."

In this case, the scientists found that if they combined a pattern of microscopic ridges or posts with a hydrophobic coating, they could create an even higher level of water resistance. That said, this level of water resistance is dependent on how the water hits the surface.

The really exciting potential for these super-hydrophobic materials, though, is how it could be used in power plants. Nearly every power plant creates energy by burning some sort of fuel to create steam that expands and rotates a turbine. Once that happens, the steam needs to be condensed back into a liquid to be cycled back through. If condensers can be built with super-hydrophobic surfaces, this process can be sped up.

"If you have these surfaces, the fluid isn't attracted to the condenser wall, and as soon as the steam starts condensing to a fluid, it just rolls right off," said Crockett in a news release. "And so you can very, very quickly and efficiently condense a lot of gas."

The findings are published in the journal Physics of Fluids.