Sustainable Energy

Researchers have developed a paint which can absorb sunlight and produce hydrogen

Peter T. Clarke | RMIT

As technology and innovation open up new ways of generating energy, some advances seem to come straight out of the science fiction playbook.

Now, researchers in Melbourne, Australia have developed a "solar paint" which is capable of absorbing water vapor and then splitting it to produce hydrogen, a clean source of energy.

In a news release earlier this month, RMIT University said the paint contained a newly developed compound which behaved like silica gel. The university added that unlike silica gel, the new material acted as a semi-conductor and was able to catalyze "the splitting of water atoms into hydrogen and oxygen."

Torben Daeneke was the lead researcher on the project. In a statement on the RMIT website, he explained how the compound, when mixed with titanium oxide particles, lead to a "sunlight absorbing paint" able to generate hydrogen fuel from solar energy and moist air.

"The developed paint offers two properties at the same time," Daeneke explained to CNBC via email. "It is strongly water absorbing, so it can take water vapor out of air… (and) it absorbs solar energy and uses that energy to split the water into hydrogen and oxygen gases. Hydrogen is a clean and green fuel."

According to the U.S. Office of Energy Efficiency and Renewable Energy, hydrogen can be used in fuel cells to produce power, with water and heat the only by-products.

Daeneke went on to explain that the real world applications of the work being done by himself and his colleagues were diverse.

"We are currently optimizing the system to maximize the hydrogen production rate and to facilitate the collection of the produced fuel," he said. "Ultimately we envisage using the solar paint as a cheap alternative to traditional photovoltaics." Photovoltaics, also known as solar PV, refers to a way of directly converting sunlight into electricity.

"The solar paint might be particularly suitable to cover wall surfaces that do not receive enough light to make solar cells economically viable, while receiving enough light to produce hydrogen with this low cost alternative," Daeneke said.

Daeneke's colleague, Kourosh Kalantar-zadeh, told CNBC that the environmental benefits of the paint were another positive. "The paint will help to reduce our reliance on fossil fuels," Kalantar-zadeh, a distinguished professor at RMIT's School of Engineering, said.

"Today about 95% of all hydrogen is produced from fossil fuels, which contribute to greenhouse gas emissions," he added. "Hydrogen as an energy carrier will also reduce the reliance on lithium ion batteries. The mining of lithium salts creates significant damage to the environment."