Scientists Create Solar Cells that Produce Electricity and Hydrogen Fuel

By Ramon Mejia

Researchers in the Netherlands have created a new type of solar cell that not only produces electrify but also breaks down water into its component parts (Hydrogen and Oxygen) while it does so. Oh, and it does it more efficiently and uses 10,000 times less precious materials than traditional methods..

The secret to these new prototype solar cells are gallium phosphide nanowires, which can split water into its hydrogen and oxygen components far more cheaply and efficiently than the batteries and semiconductor materials that have been used in the past. This makes this type of solar cells very attractive since it’s doing double duty providing electricity for homes and businesses and hydrogen to power the transportation industry of the future. 

A team Eindhoven University of Technology investigated the potential of gallium phosphide (GaP), which is a compound of gallium and phosphide that’s also used in the production of red, orange, and green-coloured LED lights, and has shown great potential in terms of its electrical properties. But gallium phosphide is expensive to produce, and when used in big, flat sheets, it’s not capable of absorbing sunlight as efficiently as needed for a viable solar cell system. So the researchers tried producing a grid of tiny gallium phosphide nanowires measuring 90 nanometres thick and 500 nanometers long, and integrated them with existing solar cell technology.

Not only did they end up using 10,000 less gallium phosphide than if they’d used it to build a flat surface, but they discovered a whole new way to make solar fuel. "This immediately boosted the yield of hydrogen by a factor of 10 to 2.9 percent," the press release explains. "A record for GaP cells, even though this is still some way off the 15 percent achieved by silicon cells coupled to a battery."

So not only did the Eindhoven team make solar cells using less expensive material but also increased efficiency of the hydrogen production at the same time. This one two combo makes the product very attractive to nations like the Netherlands, Finland, and Japan. All of whom have made large investments in alternative energy projects to help power their nations.

The more technical details of the project originally appear in Nature Communications.