Researchers from Cambridge University have developed an artificial leaf that generates clean fuel from both sunlight and water. The artificial leaves can be used on water in riverways or at sea, meaning that they could be operated at a large scale without taking up valuable land space.
Before creating the artificial leaves, the researchers were faced with a challenge - protecting the light absorbers from water infiltration. To overcome this, they used thin-film metal oxides and perovskites - a material that can be coated onto metal foils and flexible plastic. Next, they covered the artificial leaf device with a micrometre thin, water-repellent carbon-based layers. These layers helped to prevent moisture degradation.
After testing the new artificial leaves, the researchers discovered that they can effectively split water into hydrogen and oxygen, creating a clean fuel alternative to fossil fuels. The researchers also found that the leaves convert sunlight into fuel as efficiently as plant leaves.
However, the benefits don’t end there. The leaf’s ultra-thin and flexible design mean that they are light enough to float, and ‘could be placed pretty much anywhere’. Their flexibility and the fact that they work on water also means that the technology could be scaled-up and help to provide countries with more energy security, as they wouldn’t be competing with other renewable energy technologies, such as wind and solar. In addition, the artificial leaves have a very low production cost, meaning that they could potentially be a very cost-effective option for clean fuel.
The leaves could also potentially help to reduce the global shipping industry’s reliance on fossil fuels, and thus help to reduce global carbon emissions within the transport industry.
“These could supply coastal settlements, remote islands, cover industrial ponds, or avoid water evaporation from irrigation canals.” said Dr Virgil Andrei from Cambridge’s Yusuf Hamied Department of Chemistry.
While additional improvements need to be made before the devices are ready to be used commercially, it is certainly encouraging that sustainable fuel could be generated in such a way. The team envisions that the artificial leaves will be used in a similar way to solar farms, but for fuel synthesis.