wiredinUSA May 2012

INDEX

MAKING THENEWS Nanowire captures more energy A research teamat theUniversity of California, San Diego is creating a forest of nanowire trees to harvest solar energy for generating hydrogen fuel without utilizing fossil fuels.

Deli Wang, one of the researchers, explained that light is grabbed and adsorbed by the vertical structure and branches of the nanowire trees, but is reflected by flat surfaces. The research team imitated this nanostructure in its 3D branched nanowire array, which utilizes a photoelectrochemical water-splitting process to generate hydrogen gas without any greenhouse gas by product. The vertical nanotree structure also improves the output of hydrogen gas by rapidly extracting very tiny hydrogen gas bubbles, and the vertical branch structure increases the surface area at least 400,000 fold for chemical reactions. The research team’s next step is artificial photosynthesis. The team plans to imitate this process to harvest carbon dioxide from the surroundings in order to decrease carbon emissions and produce hydrogen fuel from it.

Electronic microscopic image of a nanoforest, or 3D branched nanowire array

According to the team, nanowires made of commonly available materials such as zinc oxide and silicon can be used as a low-cost source for generating hydrogen fuel on a large scale. The study findings have been published in the journal, Nanoscale.

wiredInUSA - May 2012

9

8

wiredInUSA - May 2012