New solar paint turns moist air into clean energy

 Melbourne: Scientists have developed a new solar paint that can absorb water vapour and split it to generate hydrogen - the cleanest source of energy.

The paint contains a newly developed compound that acts like silica gel, which is used in sachets to absorb moisture and keep food, medicines and electronics fresh and dry.

However, unlike silica gel, the new material, synthetic molybdenum-sulphide, 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 Torben Daeneke, from RMIT University in Melbourne, Australia.

"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," said Daeneke, lead researcher of the study published in the journal ACS Nano.

"Our new development has a big range of advantages. There is no need for clean or filtered water to feed the system. Any place that has water vapour in the air, even remote areas far from water, can produce fuel," he said.

Professor Kourosh Kalantar-zadeh, also from RMIT University, said hydrogen was the cleanest source of energy and could be used in fuel cells as well as conventional combustion engines as an alternative to fossil fuels.

"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.

"This is an extraordinary concept - making fuel from the sun and water vapour in the air," Kalantar-zadeh said.