March 9, 2009
Coated nano mesh gets more out
a net-like nanostructure made of one titanium semiconductor with a
second titanium semiconductor and you can boost the amount of light
the structure converts to electricity, and possibly the amount of
hydrogen it extracts from water.
A nanoscale mesh of titanium disilicide coated with titanium
dioxide generates about 39 percent more electricity from ultraviolet
light than titanium dioxide alone. The coated structure has a peak
efficiency of 16.7 percent compared to 12 percent for titanium dioxide.
Titanium dioxide is a good catalyst for splitting water into
hydrogen and oxygen, but it doesn't conduct electricity well. Titanium
disilicide is a better conductor. Combining the materials results
in more electrons harvested from the same number of absorbed photons.
The energy drives the chemical reaction that splits the water molecules.
Neither titanium semiconductor absorbs visible light, however.
This limits the amount of energy the materials can generate from sunlight.
Ultraviolet makes up only about 4 percent of sunlight. Adding tungsten
boosts the nanostructure's visible light conversion efficiency to
Heterostructures for High-Efficiency Photoelectrochemical H2O Splitting
Journal of the American Chemical Society, published online
February 11, 2009
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mesh conducts better -- previous development
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March 9, 2009
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