Researchers Develop Solar-Powered Artificial Leaves That Convert CO2 and Water into Liquid Fuels Suitable for Direct Use in Car Engines.
Artificial leaves attached to a metal support. (Photo: Motiar Rahaman)
A research team at the University of Cambridge harnesses the power of photosynthesis—the process by which plants convert sunlight into energy—to transform CO2, water, and sunlight into multi-carbon fuels (including ethanol and propanol) in a single step, as reported by the Independent on May 18. These fuels have high energy densities, making them easy to store and transport. Unlike fossil fuels, they have a net carbon emission of zero and are fully renewable.
The new fuels also do not occupy agricultural land. “Biofuels like ethanol are still controversial, particularly because they often use up agricultural land that could be used for food production,” said Professor Erwin Reisner, the head of the research team.
According to the research team, the new artificial leaves represent a significant step toward breaking free from a fossil fuel-dependent economy. “Typically, when attempting to convert CO2 into another chemical product using artificial leaves, you almost always end up with carbon monoxide or syngas. However, here, we have produced liquid fuel solely by using solar energy,” said Dr. Motiar Rahaman, a member of the research team.
Bioethanol is considered a cleaner alternative to gasoline as it is produced from plants rather than fossil fuels. Many cars and trucks on the road today run on gasoline that contains up to 10% ethanol (E10 fuel).
According to a study published in the journal Nature Energy, the new artificial leaves can directly produce clean ethanol and propanol without the need for an intermediate step—generating syngas. Previously, several other research groups had produced similar chemicals using electricity. However, this is the first time such complex chemicals have been produced using artificial leaves powered solely by solar energy.
Currently, the new artificial leaves are still in the experimental phase and demonstrate modest efficiency. The team of scientists is working to improve the light-absorbing components, enhancing their ability to capture sunlight while optimizing catalysts to convert more light into fuel.
