Butterflies are beautiful, delicate marvels of nature. While their lovely appearance may be inspiring, there’s nothing a butterfly can teach us about renewable energy – or is there? An ambitious University of Pennsylvania professor named Shu Yang recently used holographic lithography to develop a material that mimics the iridescent and water-resistant qualities of butterfly wings. The project garnered enough attention that the teacher landed a grant to develop butterfly-inspired hydrophobic coatings for drier, cleaner and hence more efficient solar panels.Butterfly Wing photo from Shutterstock
Most of us aren’t even aware of what makes real butterfly wings so pretty, so the idea of recreating the effect in a static material is even more mind-boggling. New Scientist explains how it works:
“Yang used holographic lithography to recreate the wings’ reflective properties, using a laser to make a 3D cross-linked pattern in a kind of material called photoresist. A solvent then washes away all the photoresist untouched by the laser, creating the 3D structure that affects light to create the colour effects. Then a poorer solvent roughens the surface, creating the texture that makes butterfly wings water-resistant.”
While a more beautiful solar panel certainly wouldn’t be a bad thing, you might be wondering why Yang went through all this trouble to make panels that imitate the butterfly. Apparently, it’s a case of form influencing function – solar panels spend a lot of time directly exposed to the elements. When dirt and moisture builds up on the surface, efficiency decreases–drastically. Yang’s special coating could help preserve solar efficiency by keeping panels clean and dry without a lot of extra effort.
In the future, Yang envisions covering entire buildings with the iridescent substance. The coated buildings could be connected to a chip that lets the owners change the color and transparency. There wouldn’t be any specific energy conservation gains, but it sure would be beautiful.
Lead image via Advanced Functional Materials