Friday, August 01, 2008

A New Kind Of Solar Cell

The boffins are at it again They have just invented a new kind of solar cell that produces hydrogen from salt water.

In Situ Formation of an Oxygen-Evolving Catalyst in Neutral Water Containing Phosphate and Co2+

Matthew W. Kanan 1 and Daniel G. Nocera 1*

The utilization of solar energy on a large scale requires its storage. In natural photosynthesis, energy from sunlight is used to rearrange the bonds of water to O2 and H2-equivalents. The realization of artificial systems that perform similar "water splitting" requires catalysts that produce O2 from water without the need for excessive driving potentials. Here, we report such a catalyst that forms upon the oxidative polarization of an inert indium tin oxide electrode in phosphate-buffered water containing Co2+. A variety of analytical techniques indicates the presence of phosphate in an approximate 1:2 ratio with cobalt in this material. The pH dependence of the catalytic activity also implicates HPO42– as the proton acceptor in the O2- producing reaction. This catalyst not only forms in situ from earth-abundant materials but also operates in neutral water under ambient conditions.
There are two possible flies in this ointment.

Indium is not abundant.


It will be interesting to see if this can be manufactured at a reasonable cost.

The New York Times has more.

H/T Just One Minute

Update 02 Aug 008 1415z

Commenter Bill Woods at Classical Values tells me that this is not a solar cell but a more efficient way to separate hydrogen from oxygen. He is right.

Cross Posted at Classical Values

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