Gold Material Cuts Glare, Repels Water

An accidental discovery has scientists looking at light glare through new eyes.

Researchers from the University of California, Irvine, were in the process of designing a flexible film to coat various products when they inadvertently developed a surface capable of eliminating glare. The team has created a patterned polymer material as a result of the findings.

The flexible material is capable of eliminating glare and repelling liquids. Courtesy of UC Irvine.

"We found that a very simple process and a tiny bit of gold can turn a transparent film black," said Robert Corn, professor of chemistry at UC Irvine.

Creating the new material involved etching a repeating pattern of cones, modeled after moth eyeballs at the nanoscale level, onto Teflon and other nonstick surfaces. The researchers next applied a thin layer of gold over the nanocones.

The study demonstrated that the gold nanocone arrays had a reflectivity of less than 1 percent over a spectral range from 450 to 900 nm, and a range of incident angles, some up to 70 degrees. This unique optical response is the result of a combination of diffractive scattering loss and localized plasmonic absorption.

The discovery, for which UC Irvine has filed a patent, could eliminate glare from solar panels and electronic displays such as on cellphones, the researchers say. It also could be used on military weapons and equipment. Eliminating glare that reflects off helmets, weapons and other gear would greatly reduce or eliminate detection by enemy troops.

The researchers have also found that the newly developed material repels liquids while acting as an adhesive. In their study, the researchers describe it as “a gecko type of surface on which a water droplet has a high contact angle, but stays in place.” Potential applications for this include self-cleaning superhydrophobic surfaces and dispensing of aqueous droplets onto hybrid superhydrophobic or hydrophilic microarrays.

The work is published in Nano Letters (doi: 10.1021/nl403496a). Related research is also published in ACS Applied Materials & Interfaces (doi: 10.1021/am500735v).

For more information, visit: www.uci.edu