Friday, March 13, 2009

"NANOTECH: Nanowires could make fuel cells commercially viable"

Woven nano-wire electrodes could provide hydrogen fuel cells the boost needed to make them commercially viable, according to a University of Rochester researchers. Nanowires have aspect ratios in the millions, enabling them to expose thousands of times more surface area than traditional platinum electrodes, thereby potentially boosting efficiency, reducing cost and increasing the longevity of hydrogen fuel cells. Li previously perfected a method of spinning out polymer nanowires with extremely high aspect ratios. He adapted the technique to spinning out individual platinum nanowires that are centimeters long but only nanometers wide. The resulting woven nanowire electrodes require much less platinum than traditional electrodes, potentially extending fuel cells beyond niche markets and into mainstream applications.

BOTTOM LINE: There are many things holding back the predicted hydrogen economy where consumers will drive electric-motor powered cars whose energy is supplied by fuel cells. One hold-up is the speed and efficiency with which electrical energy can be drawn from and supplied to fuel cells during driving and recharging, respectively. Woven nanowire electrodes appear to provide a solution to the efficiency problem, but are still in the proof-of-concept stage, whereas rival electrode technologies using nanoparticle coatings are further along in development. Durability tests will ultimately decide whether nanowires or nanoparticles provide the best solution, but the hold-up to commercialization also involves developing a hydrogen infrastructure for refueling cars, so we may see this technology first used for powering portable devices, within three years.