Researchers in the lab of Asst. Prof. Chibueze Amanchukwu at the University of Chicago Pritzker School of Molecular Engineering (UChicago PME) have spent three years looking for failure, scouring the academic literature for tales of battery breakdowns and degraded electrolytes.
"If somebody complains, 'Oh, this compound degrades in this manner and leads to a poorly cycling battery,' we get excited about that," Amanchukwu said. "Because we can flip it around for PFAS degradation."
Working with researchers from Northwestern University , the UChicago PME team turned the conditions that unfortunately degrade battery components into a new, powerful technique for intentionally degrading the water pollutants known as per- and polyfluoroalkyl substances, or PFAS.
Their results, published today in Nature Chemistry , show remarkable results in breaking down the long-chain PFAS molecule perfluorooctanoic acid (PFOA) into mineralized fluorine without forming short molecular chains that can be even tricker to remove from water. This new fluorine source can be used to create PFAS-free compounds, turning pollutants into valuable commercial products.
"We achieve about 94% defluorination and 95% degradation. That means we break nearly all the carbon–fluorine bonds in PFAS," said first author Bidushi Sarkar, a UChicago PME postdoctoral researcher. "We are mainly mineralizing and pushing complete breakdown of PFAS instead of just chopping it into shorter fragments."
University of Illinois Chicago Chemical Engineering Prof. Brian Chaplin, who was not involved in the research, praised it as "a useful conceptual advance for future reductive PFAS treatment strategies."
"This work is novel in its thoughtful use of lithium‑mediated electroreduction, instead of the more common oxidative pathways, to achieve high PFOA conversion and near‑complete defluorination in a non‑aqueous system without generating shorter‑chain PFAS byproducts," Chaplin said.
As researchers across the globe build ways to destroy the tenacious PFAS molecules through UV light, high temperatures, plasmas, plastic-hungry microbes or other means, this new work sees electrochemistry – the dance between electricity and molecular bonds – joining the fight.
"The reason people love electrochemistry is that it is quite modular," Amanchukwu said. "I can have a solar panel with batteries, and I can have an electrochemical reactor on site that is small enough to deal with any local waste streams. You don't need a large plant that operates at high temperatures or high pressures, which are in some of the systems that people are trying to build today."
Stubborn chemicals, a stubborn question
PFAS are a class of thousands of durable, resilient chemicals used in products including firefighting foams, raincoats, non-stick pans and even the lab coats the team wore during the research. But that durability makes PFAS so difficult to remove from ground, surface or drinking water that they've earned the nickname "forever chemicals."
"All of these properties – fire resistant, water resistant, oil resistant – are because of these strong carbon-fluorine bonds in PFAS," Sarkar said. "These properties that make PFAS so useful are also what make them so difficult to degrade."
This PFAS research marks new ground for UChicago PME's Amanchukwu Lab, which focuses on designing electrolytes for the batteries and electrocatalytic reactors needed to transition the planet off fossil fuels. But after conference presentations and other lectures, Amanchukwu, Sarkar and their team members kept getting questions about a different environmental concern.
"No exaggeration, when I would give talks, I guarantee you a question I would get at the end would be 'Professor, why are you making more forever chemicals?'" Amanchukwu said.
While the Amanchukwu Lab is pioneering PFAS-free battery electrolytes , many electrolytes contain PFAS, currently in small amounts and not of the type known to cause cancer or other health problems. Rather than dismiss the question, however, the team flipped it: If PFAS-based electrolytes already degrade in batteries, what can scientists learn from that?
The hunt for failure
"The electrochemistry is simply putting electrodes into a solvent," said Northwestern University Chemistry Prof. George Schatz , a co-author of the new work. "If you have these molecules dissolved into solvents, and then you pass current from the electrodes through the solvent, Chibueze and his team developed a scheme where that destroys the PFAS."
Just zapping water isn't enough. Breaking down PFAS by oxidizing them – removing electrons until the bonds linking the atoms become unstable – is difficult because of fluorine's chemical properties.
"Fluorine is the most electronegative element, so it really loves electrons," Amanchukwu said. "This makes oxidizing fluorinated compounds hard to do. It is much easier to reduce them."
Trying to reduce the compounds – adding electrons until the bonds become unstable – kept reducing the surrounding water instead, breaking the water down into hydrogen and oxygen. Studying papers showing PFAS unintentionally degraded in water-free battery electrolytes led to a new plan.
"Our innovation here was working with non-aqueous electrolytes that have high reductive stability, such that when we add a fluorinated compound to it, it's the fluorinated compound that is reductively degraded," Amanchukwu said. "That has been the breakthrough that has made this possible."
Treating copper electrodes with the lithium commonly found in batteries finalized the new procedure. Applying their success with PFOA to other members of the massive "forever chemical" family proved promising for future work. Of the 33 PFAS compounds tested, 22 demonstrated degradation amounts exceeding 70%, with some degradation up to 99%.
"People have done electrochemistry for a long time," Schatz said. "If it was easy, it would have already been discovered."
The findings were the result of a collaboration built through the Advanced Materials for Energy-Water Systems (AMEWS) Center , an Energy Frontier Research Center sponsored by the U.S. Department of Energy and led by Argonne National Laboratory.
"The intention is to try to get scientists to interact with each other who might not normally interact," said Schatz. "This has been an exciting outcome associated with the AMEWS Center."
Citation: "Lithium metal-mediated electrochemical reduction of per- and poly- fluoroalkyl substances," Sarkar et al, Nature Chemistry, January 20, 2026. DOI: 10.1038/s41557-025-02057-7
Funding: This work was supported by the Advanced Materials for Energy-Water Systems (AMEWS) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Contract No. DE-AC02-06CH11357.
