INNOVATION: Novel artificial leaf produces clean gas from sunlight

Scientists have developed an ‘artificial leaf’ device that uses sunlight to supply a widely-used gas currently made up of fossil fuels, and will be wont to create a sustainable liquid fuel alternative to petrol. The carbon-neutral device can directly produce the gas — called syngas — during a sustainable and straightforward way from CO2 and water, setting a replacement benchmark within the field of solar fuels.

Rather than running on fossil fuels, the synthetic leaf developed by researchers at the University of Cambridge within the UK is powered by sunlight, although it still works efficiently on cloudy and overcast days.

Unlike the present industrial processes for producing syngas, the leaf doesn’t release any additional CO2 into the atmosphere, consistent with the research published within the journal Nature Materials.

Syngas is currently made up of a mix of hydrogen and carbon monoxide gas , and is employed to supply a variety of commodities, like fuels, pharmaceuticals, plastics and fertilisers.

“You might not have heard of syngas itself but a day , you consume products that were created using it. having the ability to supply it sustainably would be a critical step in closing the worldwide carbon cycle and establishing a sustainable chemical and fuel industry,” said Professor Erwin Reisner from Cambridge.

The device is inspired by photosynthesis — the natural action by which plants use the energy from sunlight to show CO2 into food.

On the synthetic leaf, two light absorbers, almost like the molecules in plants that harvest sunlight, are combined with a catalyst made up of the naturally abundant element cobalt.

When the device is immersed in water, one light absorber uses the catalyst to supply oxygen.

The other carries out the reaction that reduces CO2 and water into carbon monoxide gas and hydrogen, forming the syngas mixture.

The researchers discovered that their light absorbers work even under the low levels of sunlight on a rainy or overcast day.

“This means you’re not limited to using this technology just in warm countries, or only operating the method during the summer months,” said PhD student Virgil Andrei, first author of the research.

“You could use it from dawn until dusk, anywhere within the world,” Andrei said.

Heidi Phillips