Copper–Aluminum Material Captures PFAS 1,000 Times Better Than Existing Methods
Rice University researchers report regenerable system to rapidly remove and destroy toxic forever chemicals from water
Rice University researchers, in collaboration with international partners, report a regenerable, eco-friendly technology that captures and thermally decomposes PFAS in water, according to a paper in Advanced Materials. The findings address one of the world’s most persistent environmental threats.
The study was led by Youngkun Chung, a postdoctoral fellow under the mentorship of Michael S. Wong, a professor at Rice’s George R. Brown School of Engineering and Computing, and conducted in collaboration with Seoktae Kang, professor at the Korea Advanced Institute of Science and Technology (KAIST), and Keon-Ham Kim, professor at Pukyung National University in South Korea. The paper was published online September 25, 2025.
PFAS, short for per- and polyfluoroalkyl substances, are synthetic chemicals first manufactured in the 1940s and used in products ranging from Teflon pans to waterproof clothing and food packaging. Their ability to resist heat, grease and water has made them valuable for industry and consumers. But that same resistance means they do not easily degrade, earning them the nickname “forever chemicals.”
PFAS are now found in water, soil and air around the globe. Studies link them to liver damage, reproductive disorders, immune system disruption and certain cancers, according to the National Institute of Environmental Health Sciences.
Traditional PFAS cleanup methods typically rely on adsorption, where molecules cling to materials like activated carbon or ion-exchange resins. While these methods are widely used, they come with major drawbacks: low efficiency, slow performance, limited capacity and the creation of additional waste that requires disposal.
“Current methods for PFAS removal are too slow, inefficient and create secondary waste,” said Wong, the Tina and Sunit Patel Professor in Molecular Nanotechnology and professor of chemical and biomolecular engineering, chemistry and civil and environmental engineering. “Our new approach offers a sustainable and highly effective alternative.”
Traditional vs. Advanced PFAS Removal
How the new layered double hydroxide technology compares to conventional water treatment methods
Traditional Methods
LDH Technology
The Rice-led team’s innovation centers on a layered double hydroxide (LDH) material made from copper and aluminum, first discovered by Kim as a graduate student at KAIST in 2021. While experimenting with these materials, Chung discovered that one nitrate-intercalated formulation could adsorb PFAS with record-breaking efficiency.
“To my astonishment, this LDH compound captured PFAS more than 1,000 times better than other materials,” said Chung, a lead author of the study and now a fellow at Rice’s WaTER (Water Technologies, Entrepreneurship and Research) Institute and Sustainability Institute. “It also worked incredibly fast, removing large amounts of PFAS within minutes, about 100 times faster than commercial carbon filters.”
The paper reports a maximum adsorption capacity (qmax) for PFOA of approximately 1,702 mg·g⁻¹ at neutral pH and room temperature, with adsorption kinetics of k₁ = 13.2 h⁻¹. The material’s effectiveness stems from its unique internal structure. Its organized copper-aluminum layers combined with slight charge imbalances—specifically Al-Al clash within the cationic layers creating basal plane disorder—create an ideal environment for PFAS molecules to bind with both speed and strength.
To test the technology’s practicality, the team evaluated the LDH material in river water, tap water and wastewater. In all cases, it proved highly effective, performing well in both static and continuous-flow systems. The results suggest strong potential for large-scale applications in municipal water treatment and industrial cleanup.
Three-Step Remediation Cycle
How the technology captures, destroys, and regenerates for repeated use
Step 1: Rapid PFAS Capture
The copper-aluminum layered double hydroxide (LDH) material features organized layers with nitrate intercalation and slight charge imbalances that create an ideal environment for PFAS molecules to bind quickly and strongly. The high interlayer crystallinity of the nitrate-intercalated CuxAl LDH enables boundary-breaking performance.
Testing showed the material achieved a PFOA maximum adsorption capacity of 1,702 mg·g⁻¹ at neutral pH and room temperature with adsorption kinetics of k₁ = 13.2 h⁻¹. The team evaluated the LDH in river water, tap water and wastewater, proving effectiveness in both static and continuous-flow systems—critical for practical applications in water treatment facilities.
Step 2: Thermal Destruction Without Toxic Byproducts
Removing PFAS from water is only part of the challenge. Destroying them safely is equally important. Working with Rice professors Pedro Alvarez and James Tour, Chung developed a method to thermally decompose PFAS captured on the LDH material.
By heating the saturated material with calcium carbonate at approximately 773 K (500°C), the team achieved approximately 54% defluorination without releasing toxic by-products. This thermal mineralization process converts the fluorine in PFAS into stable minerals like calcium fluoride, addressing a critical challenge: safely eliminating PFAS rather than just concentrating them elsewhere.
Step 3: Material Regeneration Enables Reuse
The thermal decomposition process regenerates the LDH material, allowing it to be reused multiple times. Laboratory studies showed the material could complete at least six full cycles of capture, destruction and renewal while maintaining effectiveness.
This regeneration capability makes the system a sustainable platform for PFAS removal, addressing both efficiency and environmental sustainability concerns. The ability to reuse the material multiple times reduces waste and operational costs, making it practical for large-scale water treatment applications.
Performance Metrics
Key performance indicators from laboratory and real-world water testing
The material’s performance remained strong across different water sources—river water, tap water and wastewater—and in both static tests and continuous-flow setups. This versatility points to possible applications in municipal water treatment systems and industrial cleanup operations.
“We are excited by the potential of this one-of-a-kind LDH-based technology to transform how PFAS-contaminated water sources are treated in the near future,” Wong said. “It’s the result of an extraordinary international collaboration and the creativity of young researchers.”
Key Technical Advances
Complete Capture-Destroy-Regenerate System
Unlike traditional methods that only capture PFAS and create secondary waste requiring disposal, this system captures AND destroys the chemicals in a closed loop. The research documents a regenerable PFAS remediation platform that combines rapid cleanup with thermal mineralization and material reuse.
Real-World Water Testing
The team tested the LDH material in actual water sources—rivers, tap water and wastewater—not just laboratory conditions. Performance remained strong in both static and continuous-flow systems, critical factors for practical applications in water treatment facilities worldwide.
Material Discovery Background
The copper-aluminum layered double hydroxide material was first discovered by Keon-Ham Kim while he was a graduate student at KAIST in 2021. Youngkun Chung later discovered that a specific nitrate-intercalated formulation could adsorb PFAS with exceptional efficiency during experiments at Rice University.
International Research Collaboration
This work resulted from collaboration between Rice University researchers and partners at Korea Advanced Institute of Science and Technology (KAIST) and Pukyung National University in South Korea. The research received support from the National Research Foundation of Korea, U.S. Army Corps of Engineers, and Rice’s WaTER Institute and Sustainability Institute.
The Research Team
The research was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, grants from the National Convergence Research of Scientific Challenges and the Sejong Science Fellowship through the National Research Foundation of Korea, and funding from the Ministry of Science and ICT. Additional funding came from Saudi Aramco-KAIST CO2 Management, Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), the U.S. Army Corps of Engineers’ Engineering Research and Development Center grant, Rice Sustainability Institute and Rice WaTER Institute.
The study was published in Advanced Materials (DOI: 10.1002/adma.202509842). The team’s findings represent a step forward in addressing water contamination challenges that affect communities worldwide.
Related Resources and Further Reading
Water Treatment Innovations
PFAS Contamination Context
Health and Environmental Impact
