Scientists Develop Integrated Module That Can Split Water to Produce Energy

The device uses water and sunlight to get chemical fuel


Researchers at Rice University in the United States of America have created a low-cost device that can split water to produce hydrogen fuel.

The device is developed by the Brown School of Engineering lab at Rice University. The research team led by scientist Jun Lou integrated catalytic electrodes and perovskite solar cells; when this was triggered by sunlight, producing electricity.

According to the university’s release, the current flows to the catalysts, which can split water into hydrogen and oxygen, with a sunlight-to hydrogen efficiency as high as 6.7%.

The scientists claim that the laboratory packaged a perovskite layer and the electrodes into a single module that, when dropped into water placed in the sunlight, will produce hydrogen.

Lou said, “The concept is broadly similar to an artificial leaf. What we have is an integrated module that turns sunlight into electricity that drives an electrochemical reaction. It utilizes water and sunlight to get chemical fuels.”

Perovskites are crystals with cubelike lattices that are known to harvest light. The most efficient perovskite solar cells produced so far achieve an efficiency above 25%, but the materials are expensive and tend to be stressed by light, humidity, and heat, the report stated.

“Even when there’s no sunlight, you can use the stored energy in the form of chemical fuel. You can put the hydrogen and oxygen products in separate tanks and incorporate another module like a fuel cell to turn those fuels back into electricity,” Lou added.

According to the lead author and Rice postdoctoral fellow Jia Lang, the key component may not be the perovskite but the polymer that encapsulates it, thus protecting the module and allowing it to be immersed for long periods.

“Others have developed catalytic systems that connect the solar cell outside the water to immersed electrodes with a wire,” he said.

Further, Liang said that the patterned film allows sunlight to reach the solar cell while protecting it and serves as an insulator between the cells and the electrodes.

The researchers claim that with proper system design, one can potentially make a self-sustaining loop.

Previously, researchers at Stanford said they had developed a water-based battery that can provide a better solution than lithium-ion for storing solar and wind energy.

Recently, Mercom had reported that Australian scientists, led by the ARC Center of Excellence in Exciton Science, had published a research paper that stated that they have succeeded in producing semi-transparent perovskite solar cells that can generate electricity. The breakthrough could allow windows in buildings and automobiles to generate electricity.

Image credit: Oregon Department of Transportation / CC BY (2.0)