Fuel of the Future: New Research Says Water Could Power the World

Solar fuels, created using water, sunlight and carbon dioxide, is the dream of clean energy enthusiasts all over the world. A team of researchers from Caltech University and the Lawrence Berkeley National Laboratory (Berkeley Lab) recently made strides in achieving this eco-friendly fuel by discovering a host of materials that could make it possible.

The key to these types of fuel -- from hydrogen gas to liquid hydrocarbons -- is being able to split water, according to a report from Caltech. Water molecules are made up of one oxygen atom and two hydrogen atoms, and the hydrogen atoms need to be isolated and either reunited or combined with carbon dioxide to create an energy source.

Splitting water isn't quite so simple though; a solar-powered catalyst is necessary. For this reason, scientists have been trying to develop photoanodes, which are materials that can split water with light as an energy source.

Sixteen photoanodes have been identified over the last four decades, but the researchers from Caltech and Berkeley Lab were able to almost double that number by developing a high-throughput process that speeds up the discovery of new materials. In the past two years alone, the team discovered 12 photoanodes.

Led by Caltech's John Gregoire and Berkeley Lab's Jeffrey Neaton and Qimin Yan, the group combined computational and experimental approaches. First, they scoured a minerals database for potential materials, then tested these in high-throughput experimentation.

"What is particularly significant about this study, which combines experiment and theory, is that in addition to identifying several new compounds for solar fuel applications, we were also able to learn something new about the underlying electronic structure of the materials themselves," Neaton, the director of the Molecular Foundry, explained.

The team's findings were published in the journal Proceedings of the National Academy of Sciences.