Researchers have found a way to use rust to build a solar-powered battery.
Image: Diego Torres Silvestre
What happens when corrosion meets energy? For researchers at Stanford University, the marriage of those two uniquely electrochemical topics could yield an answer to large-scale solar power storage.
The question of how to store solar power when the sun goes down has been on the forefront of scientific discussion. While electrochemical energy storage devices exist, they are typically either too expensive to work on a large-scale or not efficient enough.
Building a solar-powered battery
New research shows that metal oxides, such as rust, can be fashioned into solar cells capable of splitting water into hydrogen and oxygen. The research could be looked at revelatory, especially when considering large-scale storage solutions, because of its novel heat attributes.
While we knew the promising solar power potential of metal oxides before, we believed that the efficiency of cells crafted from these materials would be very low. The new study, however, disproves that theory.
The team showed that as the cells grow hotter, efficiency levels increase. This is a huge benefit when it comes to large-scale, solar energy conversion and it the polar opposite of the traditional silicon solar cell.
“We’ve shown that inexpensive, abundant, and readily processed metal oxides could become better producers of electricity than was previously supposed,” says William Chueh, an assistant professor of materials science and engineering.
Reinventing storing solar energy
Researchers believe this could change how we produce, store, and consume energy.
“By combining heat and light, solar water-splitting cells based on metal oxides become significantly more efficient at storing the inexhaustible power of the sun for use on demand,” Chueh says.
The high heat efficiency levels mean that simple engineering could be done to enhance solar cells.
“You don’t have to add energy from an outside source,” says graduate student and team member Andrey Poletayev. “You can do it for free by concentrating solar radiation, either through a magnifying lens or parabolic mirrors.”
The researchers believe that the scientific conversation behind metal oxides as a cost-effective alternative to silicon will once again make its way to the forefront in the field of renewable energy.
“We can store these gases, we can transport them through pipelines, and when we burn them we don’t release any extra carbon,” says Chueh. “It’s a carbon-neutral energy cycle.”
