• Side view scanning electron microscope image of a silicon surface textured with (a) cylindrical pillars and (b) nanocones.

    Credit: Courtesy of the Brookhaven National Laboratory

    Side view scanning electron microscope image of a silicon surface textured with (a) cylindrical pillars and (b) nanocones.

Scientists have pursued the creation of superhydrophobic—or extreme water-hating—surface treatments based on their many possible benefits for a variety of engineered materials. From steam turbines to car windshields, surfaces that encourage the rapid elimination of water without the need for added chemicals or regular maintenance are highly desirable in industrial as well as consumer arenas.

Researchers at the U.S. Department of Energy's Brookhaven National Laboratory have developed a series of superhydrophobic surfaces using nanostructures. The polymer-based structures were created via a self-assembly process called “microphase separation,” which resulted in plastic thin films with uniform textures. "For this work, we have developed a fabrication approach based on self assembly of nanostructures, which lets us precisely control the surface texture geometry over as large an area as we want—in principle, even as large as square meters,” said physicist Antonio Checco in a Brookhaven Lab press release.

The scientists explored different types of textures—such as nanocylinders and nanocones—to test their levels of hydrophobic performance. "While we fabricated several different nanotextures that all significantly increased the water repellency, certain shapes performed differently than others," said Brookhaven physicist Atikur Rahman. The researchers determined that the nanocones were far superior to the cylinders at forcing water run-off.

The Brookhaven team is currently studying the application of their superhydrophobic nanostructures on different materials, and testing them for resistance to water penetration.

Blaine Brownell, AIA, is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.