Scientists at the University of Cambridge have created an artificial leaf that uses sunlight to convert CO2 and water into ethanol and propanol. It is the first clean ready to use liquid car fuel from solar powered artificial leaf. This would eliminate the intermediate step of manufacturing syngas, making the technology more viable and paving the road for a zero-carbon future. These fuels have a high energy density and are simple to store and transfer.
Researchers have created a solar-powered technology that transforms carbon dioxide and water into liquid fuels. This liquid fuel from artificial leaf can be directly injected as drop-in fuel in the car.
The University of Cambridge researchers used photosynthesis to transform CO2, water, and sunshine into multicarbon fuels ethanol and propanol in a single process. These clean liquid fuels have a high energy density and are simple to store and transfer.
Unlike fossil fuels, these solar fuels emit no carbon dioxide and are totally renewable. They do not divert agricultural land from food production, unlike most bioethanol. While the technology is still in the lab, the researchers believe their ‘artificial leaves’ are a vital step towards moving away from a fossil-fuel-based economy.
Bioethanol is derived from plants rather than fossil fuels; thus, it is considered a cleaner alternative to petrol. Most modern cars and trucks run on E10 petrol containing up to 10% ethanol. According to the US Department of Agriculture, the United States is the world’s greatest bioethanol producer. About 45% of all maize farmed in the country is used for ethanol production.
Professor Erwin Reisner, lead researcher in the team said, â€œBiofuels like ethanol are a controversial technology, not least because they take up agricultural land that could be used to grow food instead.â€
For several years, Reisner’s research group at the Yusuf Hamied Department of Chemistry has been developing zero carbon and sustainable fuels inspired by the process of photosynthesis. The only difference being they use artificial leaves for the process.
To present, these solar powered artificial leaves or synthetic leaves have only been capable of producing simple molecules such as syngas, a mixture of hydrogen and carbon monoxide used to manufacture fuels, medicines, polymers, and fertilizers. However, in order for the technique to be more practical, it must be capable of producing more complicated molecules directly in a single solar-powered process. This removes the requirement for preparation of syngas.
Scientists created a copper and palladium-based catalyst. The catalyst was tuned in such a way that the fake leaf could make more complicated molecules, namely the multicarbon alcohols ethanol and n-propanol. Other scientists have synthesized comparable molecules using electrical power, but this is the first time that such complex chemicals have been produced with an artificial leaf using only solar energy.
Dr Motiar Rahaman, the paper’s first author, said, â€œShining sunlight on the artificial leaves and getting liquid fuel from carbon dioxide and water is an amazing bit of chemistry.
Normally, when you try to convert CO2 into another chemical product using an artificial leaf device, you almost always get carbon monoxide or syngas, but here, we’ve been able to produce a practical liquid fuel just using the power of the Sun. It’s an exciting advance that opens up whole new avenues in our work.â€
At the moment, the device is merely a proof of concept, with only minimal efficiency to produce clean liquid fuel. The researchers are attempting to improve the light absorbers’ ability to absorb sunlight and to improve the ability of the catalyst to convert more sunlight into fuel.
More effort will also be necessary to scale the gadget so that it can create significant amounts of gasoline. With advancement in technology liquid fuel from artificial leaf would soon be available as the sustainable fuel for all.
â€œEven though there’s still work to be done, we’ve shown what these artificial leaves are capable of doing. It’s important to show that we can go beyond the simplest molecules and make things that are directly useful as we transition away from fossil fuels.â€ said Reisner