Caltech chemists identify the mechanism by which such
catalysts work
PASADENA, Calif.—Scientists and engineers around the world
are working to find a way to power the planet using solar-powered fuel cells.
Such green systems would split water during daylight hours, generating hydrogen
(H2) that could then be stored and used later to produce water and electricity.
But robust catalysts are needed to drive the water-splitting reaction. Platinum
catalysts are quite good at this, but platinum is too rare and expensive to
scale up for use worldwide. Several cobalt and nickel catalysts have been
suggested as cheaper alternatives, but there is still plenty of room for
improvement. And no one has been able to determine definitively the mechanism
by which the cobalt catalysts work, making it difficult to methodically design
and construct improved catalysts.