Wrinkling Boosts Output of Organic Solar Cells
In organic photovoltaic devices, the active layer—which absorbs sunlight to generate the electrons and holes which become the output current—has a delicate balancing act. It must simultaneously be thin enough that the electrons and holes can easily be collected, yet thick enough to absorb much of the solar radiation landing upon it. In an article entitled, “Wrinkles and Deep Folds as Photonic Structures in Photovoltaics”, published recently in Nature Photonics, a Princeton team led by Professor Yueh-Lin (Lynn) Loo has come up with an ingenious solution to this conundrum. By imparting corrugations—both mild wrinkles, and deeper creases termed “folds”—they have been able to guide light into the active layer, increasing the absorption in the near-infrared by 600%, and boosting the overall output current by 47% relative to a comparable uncorrugated device. The Princeton research team also included CBE associated faculty member Professor Howard Stone from Mechanical and Aerospace Engineering, and Associate Professor Jason Fleischer from Electrical Engineering. For more information, see the School of Engineering and Applied Science’s press release, or the story on the Princeton University homepage.