Dressed for Power

ASEE Prism, Summer 2008 by Grose, Thomas K

NANOTECHNOLOGY

THE DREADED "low battery" message and darkened screens of cell phones and other hand-held devices may soon be consigned to tech history. A Georgia Tech researcher, Zhong Lin Wang, is developing a "nanogenerator" that would provide ongoing power for small devices by capturing the kinetic energy released by body movement. A network of zinc oxide nanowires would be woven into the fabric fibers of clothing to collect and then convert physical motion to electrical energy.These nanostructures have unique piezoelectric and semiconducting properties, so that when flexed, they produce small electrical charges. Wang, a professor of materials science and engineering, has embedded pairs of nanowires into Kevlar fibers, with one of each pair coated in gold to act as an electrode. He theorizes that one square meter of fabric could generate around 80 milliwatts of power. But as zinc oxide loses its effectiveness in water, Wang still has to find a way to protect his wired cloth from the damage of washing machines.-TG