A man-made leaf may hold the potential to help combat carbon dioxide emissions that lead to climate change.
Researchers at the University of Illinois at Chicago (UIC) have created an artificial leaf prototype that is designed to cut down on carbon dioxide — the main greenhouse gas behind global warming and climate change, experts say. CO2 is released by humans through things like electricity, transportation and steel production.
In 2016, carbon dioxide made up roughly 81.6% of all greenhouse-gas emissions in the US caused by humans, according to the US Environmental Protection Agency.
The researchers behind the leaf, who published their work in a recent paper in the journal ACS Sustainable Chemistry & Engineering, are the latest group to try to mimic the work that real leaves do in order to fight emissions.
Meenesh Singh, an assistant professor in UIC’s department of chemical engineering, and Aditya Prajapati, a graduate student in his lab, are behind the artificial leaf prototype. According to Singh, the artificial leaf could be 10 times more efficient than real leaves at converting carbon dioxide to cut down on climate change and produce cleaner energy.
Singh’s motivation was to create a device that could work outside of a lab.
It works in the same way trees and plants absorb carbon dioxide through leaves and turns it into the fuel they need to live. The carbon, which is turned into carbohydrates, is stored while the oxygen is released back into the atmosphere.
But the artificial leaf doesn’t produce carbohydrates the way real plants do, and instead produces carbon monoxide to create cleaner synthetic fuels. It also produces oxygen gas that can be released into the atmosphere.
Singh said the leaf can be used on a small scale such as the roof of a house or on a larger scale at, say, a powerplant.
The cube-shaped artificial leaf features an acrylic covering and was made using artificial stomata to mimic the pore-like openings on real leaves. Artificial stoma is a membrane that allows the exchange of negatively charged ions.
A lot of research is being conducted around artificial leaves and even artificial trees. But the UIC team has created a prototype that’s been tested in a lab and can work in real-world conditions.
Still, it’s unclear when something like this will be ready for large-scale commercial use.
Singh’s prototype can work using diluted forms of CO2. This more closely resembles the CO2 in the atmosphere as a byproduct of industrial processes. Most other prototypes rely on pure CO2, which is closer to the carbon dioxide found in carbonated water than it is to emissions. Because Singh’s leaf can use diluted CO2 it can pull it straight from the air and work outside of laboratory conditions. Singh said the prototype is currently being tested to see at what rate it can continuously capture carbon from the air.
Larry Curtiss, a distinguished fellow at the Argonne National Laboratory, believes technology like what’s come out of UIC could potentially be effective as a solution for decreasing harmful gases in the atmosphere.
“This type of innovative lab-scale research is one step to an eventual commercial system that can help to significantly reduce carbon dioxide emissions,” said Curtiss.
Harry Atwater, the director of the Joint Center for Artificial Photosynthesis, the largest program of its type in the US, agrees that fighting carbon emissions is critical.
Atwater said it’s becoming increasingly apparent that we don’t have the capacity to cope with what we’re putting into the atmosphere.
“[Singh] has used more dilute sources, and that’s important,” Atwater said. “It’s a big conceptual step that opens space for thinking about how we deal with [emissions].”