A team of Australian researchers have announced they’ve developed solar paint that can absorb water from the air and turn it into hydrogen that can be used to produce energy.
The paint, revealed along with a study on Tuesday, is a combination of a chemical catalyst and the white color used in toothpaste. When combined and exposed to rays of sun, it can turn water vapor into hydrogen molecules. Although it is probably at least five years away from being commercially viable, the paint is expected to be a very cheap way to use sunlight to create energy that can be transported or used to power a car. And since it’s just paint, it can be applied almost anywhere.
“Ultimately we hope that the solar paint might be used alongside traditional solar cells, potentially coating areas that receive too little light to be viably covered with expensive solar cell modules,” Torben Daeneke, a research fellow at the Royal Melbourne Institute of Technology and lead author on the discovery, tells Inverse.
To turn water into hydrogen, the paint uses a molybdenum sulphide catalyst. Some of the molecules in this group are used as lubricants, like graphite powder, and the catalyst is able to absorb water and conduct electricity. The white element in the paint, titanium oxide, draws light to the paint. Since the catalyst is a semi-conductor, it uses this energy from the sun to break the water droplets into hydrogen, says Daeneke.
“The produced hydrogen can then be directly used either in a fuel cell or in a combustion engine,” says Daeneke. To do this, the team has to apply the paint in connection with a membrane that can funnel the hydrogen to a place it can be connected. Daeneke points out that this kind of membrane technology exists today, and the team is currently working to figure out the most efficient method.
Although Daeneke things it will take at least 5 years to engineer the final product, he expects the paint will be very cheap. Since there are already cars and buses that are hydrogen powered today, Daeneke says, once the collection process is completed this could be a powerful source of clean energy in the future. And because it’s effectively just a white paint, you could put it on your house or fence to create another kind of clean energy with a little humidity and sunlight.