Researchers from the Royal Melbourne Institute of Technology (RMIT) University in Australia have developed a solar paint that can absorb water vapour from the air, and, using sunlight, splits water atoms to harvest hydrogen.

The paint contains a compound called synthetic molybdenum-sulphide, which acts like silica gel, the researchers said. But unlike silica gel, the new material also acts as a semi-conductor and catalyses the splitting of water atoms into hydrogen and oxygen.

“We found that mixing the compound with titanium oxide particles leads to a sunlight-absorbing paint that produces hydrogen fuel from solar energy and moist air,” said RMIT lead researcher Dr. Torben Daeneke. “Titanium oxide is the white pigment that is already commonly used in wall paint, meaning that the simple addition of the new material can convert a brick wall into energy harvesting and fuel production real estate.

Hydrogen, considered to be the cleanest source of energy, can be used in fuel cells as well as conventional combustion engines as an alternative to fossil fuel, according to Distinguished Professor Kourosh Kalantar-zadeh.

“This system can also be used in very dry but hot climates near oceans. The sea water is evaporated by the hot sunlight and the vapour can then be absorbed to produce fuel,” he noted.