The discovery that butterfly wings have scales that act as tiny solar collectors has led scientists in China and Japan to design a more efficient solar cell that could be used for powering homes, businesses, and other applications in the future. In the study, Di Zhang of the State Key Lab of Metal Matrix Composites at Shanghai Jiao Tong University and colleagues note that scientists are searching for new materials to improve light-harvesting in so-called dye-sensitized solar cells, also known as Grätzel cells for inventor Michael Grätzel. These cells have the highest light-conversion efficiencies among all solar cells — as high as 10 percent.A close-up of the scales of a butterfly wing, which have inspired more powerful solar cells. (Image: Michael Apel, Wikipedia Commons) The researchers turned to the microscopic solar scales on butterfly wings in their search for improvements. Using natural butterfly wings as a mold or template, they made copies of the solar collectors and transferred those light-harvesting structures to Grätzel cells. Laboratory tests showed that the butterfly wing solar collector absorbed light more efficiently than conventional dye-sensitized cells. The fabrication process is simpler and faster than other methods, and could be used to manufacture other commercially valuable devices, the researchers say. Their study, "Novel Photoanode Structure Templated from Butterfly Wing Scales," appeared in the Jan. 13 issue of the American Chemical Society's Chemistry of Materials, a biweekly journal. For more information, visit: http://pubs.acs.org