The big idea: What if you could charge your car by driving in the sunlight instead of stopping at a gas station? Thanks to associate professor of chemistry Peidong Yang, we may soon channel sunlight to power everything from houses to laptops. The technology is solar paint, an external coating made from layers of nanoparticle solar cells. The cells absorb particles of sunlight—photons—which excite electrons used to generate electricity. A zinc oxide nanowire that Yang developed two years ago moves electrons quickly and directly through the cell. “The nanowire is essentially the electron freeway,” he says.
What’s next: Significant problems remain, including improving the cell’s light absorbtion, and designing a still more efficient yet environmentally benign nanowire.