Clearing up the ‘Dark Side’ of Artificial Leaves

Typography

While artificial leaves hold promise as a way to take carbon dioxide — a potent greenhouse gas — out of the atmosphere, there is a “dark side to artificial leaves that has gone overlooked for more than a decade,” according to Meenesh Singh, assistant professor of chemical engineering in the University of Illinois at Chicago College of Engineering.

While artificial leaves hold promise as a way to take carbon dioxide — a potent greenhouse gas — out of the atmosphere, there is a “dark side to artificial leaves that has gone overlooked for more than a decade,” according to Meenesh Singh, assistant professor of chemical engineering in the University of Illinois at Chicago College of Engineering.

Artificial leaves work by converting carbon dioxide to fuel and water to oxygen using energy from the sun. The two processes take place separately and simultaneously on either side of a photovoltaic cell: the oxygen is produced on the “positive” side of the cell and fuel is produced on the “negative” side.

Singh, who is the corresponding author of a new paper in ACS Applied Energy Materials, says that current artificial leaves are wildly inefficient. They wind up converting only 15% of the carbon dioxide they take in into fuel and release 85% of it, along with oxygen gas, back to the atmosphere.

“The artificial leaves we have today aren’t really ready to fulfill their promise as carbon capture solutions because they don’t capture all that much carbon dioxide, and in fact, release the majority of the carbon dioxide gas they take in from the oxygen-evolving ‘positive’ side,” Singh said.

Read more at University of Illinois at Chicago

Image: This is a schematic depiction of an artificial leaf with a membrane that reduces the release of carbon dioxide back into the atmosphere. (Credit: Aditya Prajapati and Meng Lin)