University of Pennsylvania Engineering Professor Shu Yang and her team have mimicked the reflective and water-resistant properties of butterfly wings to create a material that could coat solar panels and increase their output by keeping them clean and dry. The efficiency of solar panels takes a major drive when moisture and debris collect on their surface, so this inventive nature-inspired solution could keep them working at their maximum efficiency, not to mention the iridescence would be beautiful to look at.
New Scientist explains how Yang made the holographic wafer material:"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."
The holographic material could also be used to coat buildings. While this wouldn't have any clean energy applications, Yang does see them as a way to make buildings more beautiful. The coated buildings could be connected to a chip that lets the owners change the color and transparency.
Yang is working under a grant to produce the hydrophobic coating for solar panels. A prototype of the material should be ready by June 2013.