Scientists hope to split water with quantum dots and nanowires

BUFFALO, N.Y., Oct. 17 (UPI) -- Photocatalytic water splitting holds tremendous promise for the hydrogen economy and the use of hydrogen as a eco-friendly alternative fuel.

Scientists at the University of Buffalo are working to develop new materials capable of powering more efficient photocatalytic water-splitting technologies.

"Hydrogen is seen as an important source of green energy because it generates water as the only byproduct when it's burned," Buffalo chemist David Watson said in a news release. "The hybrid materials we're developing have the potential to support the cheap and efficient production of hydrogen gas."

A variety of vehicles have been built to run on hydrogen, but synthesizing hydrogen fuel isn't yet cheap enough to rival the dominance of fossil fuels. Simpler and more efficient water-splitting technologies are promising to change that.

Photocatalytic water splitting uses special water-suspended materials to harness the power of the sun and trigger photosynthesis, which works to split water into hydrogen and oxygen.

The new materials being developed by Watson and his colleagues are made of tiny wires composed of vanadium oxide and various metal ions. The hybrid nanowires are coated with semiconductor quantum dots.

When exposed to sunlight, the coated nanowires generate two key components for the photocatalytic reaction: a free-floating electron and an electron hole.

While scientists have yet to use the electron and electron hole to split water, they are hopeful the new materials will provide the breakthrough proponents of the hydrogen economy have been looking for.

The materials used to create the coated nanowires are readily available, and the nanowires and quantum dots can be produced in large quantities. What's more, the materials in the nanowires and the size of the quantum dots can be manipulated to augment their electronic properties.

"It's a very flexible approach -- a versatile platform for converting sunlight and water into fuel," Watson said.

Researchers are now working on a way to incorporate their materials into a working photocatalytic water-splitting process.