wiredinUSA May 2012

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wiredInUSA - May 2012
MAKING
THENEWS
9 wiredInUSA - May 2012 8
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.
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.
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