By Prachi Patel
Lithium’s high reactivity can cause trouble in batteries based on lithium-metal anodes. The metal degrades the fluorinated electrolytes used in these batteries, affecting performance.
Because these electrolytes contain fluorine, as do PFAS, the harmful per- and polyfluoroalkyl substances that persist in the environment, Chibueze Amanchukwu says he and his colleagues at the University of Chicago wondered “can we take that disadvantage of a lithium-metal battery and apply it to PFAS destruction?”
The researchers tested their hunch by dissolving PFAS in the electrolyte solution of a lithium-containing electrochemical cell. They found that lithium indeed helps break 95% of the strong carbon-fluorine bonds in perfluorooctanoic acid (PFOA), a common PFAS (Nat. Chem. 2026, DOI: 10.1038/s41557-025-02057-7).
Instead of chopping up PFOA into smaller PFAS with shorter carbon chains, the lithium-based method breaks it down completely to lithium fluoride. The researchers reused the fluoride to make non-PFAS compounds relevant for batteries and pharmaceuticals. The team showed that the method also works to various extents on 33 other such compounds.
Most electrochemical techniques for PFAS destruction rely on oxidation: taking away electrons to break the C–F bonds. Oxidation currently works better in the aqueous conditions for which these methods have been developed, Amanchukwu says. If you try reduction—lobbing electrons at the compound to make them unstable so they fall apart—the method tends to fail. Instead of destroying PFAS, the electrons usually end up reducing water to form hydrogen.
But reducing fluorine is simpler, Amanchukwu says. “It is the most electronegative element, so giving it electrons is easier.” That’s what happens in lithium-metal batteries, in which lithium reduces the nonaqueous fluorinated electrolytes.
So the researchers recreated battery conditions for PFAS destruction. They dissolved lithium perchlorate salt in an organic solvent to make an electrolyte. They added PFOA to the electrolyte, which they placed in an electrochemical cell with copper and graphite electrodes. When they ran an electric current through the device, metallic lithium deposited on the copper surface and reacted with PFOA, breaking it apart.
The researchers found that the method was more effective when they lowered the concentration of PFOA in the electrolyte solution. Tests on 33 other PFAS compounds showed that 22 of them were degraded by more than 70%. Two PFAS, perfluorodecanoic acid and perfluoroundecanoic acid, showed 99% degradation.
“The innovation here is [that] they take advantage of battery-inspired reactive metal electrochemistry for environmental remediation,” says Christian Malapit, a chemist at Northwestern University. An important advantage of the approach is that it works on both carboxylates and sulfonates, the most common types of PFAS compounds.
PFAS are found in water and soil and would have to be captured and concentrated so they can be mixed into organic solvents to be destroyed using this method, Amanchukwu says. His group wants to see if it’s possible to develop a similar reductive system that works in aqueous media.
Of course, the problem is that lithium reacts violently with water. Malapit says that the metal’s high reactivity is a concern in general. “Lithium handling could pose safety and scalability issues,” he says, and developing a practical system “will require careful engineering.”