The photo Peng Jiang displayed was at once familiar and strange: a black-and-white picture of what looked like an alien landscape packed with uniform hills.
In fact, the "hills" are about 300 nanometers tall - about 150 times smaller than the width of a human hair.
The landscape was the eye of a moth, and the picture was taken with an electron microscope.
By studying moth eyes and cicada wings, Jiang, an assistant professor of chemical engineering at UF, and his graduate students created an anti-reflective, water-resistant coating.
The coating could lead to more efficient solar cells and glare-resistant windshields.
"Nature is a beautiful thing and has already solved so many problems," said Jiang, whose research appeared in the journal Applied Physics Letters in September.
"Now, we have to just figure out how to apply them to the real world."
Although the properties of moth eyes and cicada wings were already known, Jiang's team was the first to devise a simple and cost-effective method for manufacturing a coating that mimicked them.
The coating's anti-reflective properties are based on moth eyes.
Due to their curved surfaces, the bumps of a moth eye do not reflect incoming light back out.
As a result, moths don't give themselves away to predators in the gleam of moonlight, Jiang said.
The synthetic coating Jiang created also mimics the texture of cicada wings.
Bumps on cicada wings, which resemble the bumps on moth eyes, act to keep dirt and water from sticking to them.
Air fills the gaps between the bumps and prevents water from condensing on the surface of the wings.
"If [cicadas] had the condensation of water on their wings, they couldn't fly in humid air," Jiang said. "So, they use this micro-structure to do self-cleaning to clear away water, which also clears away dust."
The coating Jiang helped create has several potential uses.
"If you treated a window with this artificial micro-structure, you could absorb more light coming in," Jiang said. "And if the window gets dirty, you could just wait for some rain to wash it away."
If applied to a car windshield, it might not even need wipers, Jiang said. The rain would simply slide right off.
Solar cells coated with the thin film would absorb more light and stay cleaner, Jiang said.
"Right now, solar energy is about six times more expensive than coal or gas," Jiang said. "The question is: How can we reduce the fabrication price and material price? Solar cells reflect 35 to 60 percent of the light hitting it. Our coated material reflects less than two."
Jiang created his invention using a method called spin coating.
In this method, Jiang and his graduate students made a quick-setting fluid with nanoparticles suspended in it.
The solution is dripped onto a rapidly spinning surface, such as a piece of glass, which spreads the solution evenly.
The fluid hardens into a thin plastic-like film, and the nanoparticles function like the insects' bump structure.
Jiang said that this kind of process is known as self-assembly, because the nanoparticles arrange themselves on the spinning surface.
Jiang said his work is one way in which scientists are attempting to understand nature's complex systems and mimic them with technology. This field is known as biomimetics.
"I think biomimetics is so amazing," he said.
"Whenever I show this structure to anybody, to high school students, everybody gets excited," he said. "Nature is inspiring."
