ERASE-PFAS: Mechanistic Study of the Electrochemical Oxidation of Per and Polyfluorinated Alkyl Substances to Guide Electrode Design

About This Grant

Per- and polyfluoroalkyl substances (PFAS), also known as “forever chemicals,” are harmful pollutants that do not break down easily and can contaminate drinking water. This project will improve a treatment method called electrochemical oxidation, which uses electrodes made of diamond to destroy PFAS and turn them into safer compounds. Along with scientific progress, the project will support STEM education by training both undergraduate and graduate students and offering outreach programs and workshops. These efforts will help prepare a skilled workforce to address major environmental problems. The project will also support global teamwork by connecting researchers, students, and industry professionals to find better ways to handle PFAS pollution. This project aims to advance the scientific understanding and practical application of electrochemical oxidation (EO) using boron-doped diamond (BDD) electrodes for the destruction of per- and polyfluoroalkyl substances (PFAS); a class of environmentally persistent and chemically stable synthetic pollutants. PFAS, including compounds such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are highly resistant to conventional chemical, physical, and biological treatment processes, making their removal from drinking water and wastewater particularly challenging. The proposed research seeks to address current limitations in EO treatment by investigating the mechanistic basis of PFAS degradation at BDD electrode surfaces, and by optimizing electrode design and treatment cell configuration to improve PFAS mineralization efficiency. The project is structured around the following technical objectives: (1) elucidate the fundamental degradation mechanisms and kinetics of PFAS during EO, with a focus on both direct electron transfer and indirect oxidation pathways involving hydroxyl radicals; (2) evaluate the influence of operational parameters including applied potential, current density, electrolyte composition, flow dynamics, and electrode surface morphology, on PFAS degradation rates and energy efficiency; (3) design and fabricate novel BDD electrode architectures and flow-through reactor configurations that enhance mass transport, reduce energy demand, and improve long-term system treatment stability; and (4) validate the performance of the optimized EO system in treating real-world PFAS-contaminated water samples, such as groundwater, landfill leachate, and ion exchange brine reject. To achieve these objectives, the research team will conduct systematic EO experiments using model PFAS compounds under controlled laboratory conditions. Advanced analytical techniques including ion chromatography, high-resolution mass spectrometry, total organic fluorine analysis and others will be employed to track PFAS degradation, quantify fluoride release, identify transformation products, and assess defluorination efficiency. These data will be used to characterize degradation pathways and assess treatment efficiency. Complementing the experimental studies, computational modeling and quantum chemical calculations will simulate PFAS interactions with BDD surfaces, providing insight into activation energies, reactive intermediates, and rate-determining steps for both direct and indirect oxidation mechanisms. Modeling will also be used to optimize electrode geometry and reactor design, using fluid dynamics and electric field simulations to enhance mass transfer and reactive species distribution. Based on these simulations, prototype BDD electrodes with improved surface and electrical properties will be fabricated and integrated into custom-built EO cells for performance testing. Following lab-scale optimization, the new EO systems will be tested on real water matrices with complex chemical backgrounds to assess treatment robustness, matrix effects, and system scalability. These evaluations will provide a critical bridge between bench-scale research and field-scale implementation, ensuring that the developed technologies are viable under realistic environmental conditions. The broader impact of this project lies in translating fundamental electrochemical and materials science insights into practical technologies for PFAS remediation across municipal, industrial, and agricultural settings. The research outcomes will inform structure-reactivity relationships governing PFAS degradation on BDD electrodes, support the rational design of high-efficiency EO systems, and define operational strategies that maximize PFAS destruction while minimizing energy consumption and undesirable byproduct formation. By addressing a pressing water quality challenge with a scientifically rigorous and engineering-forward approach, this project will contribute to the development of sustainable, scalable solutions for mitigating PFAS contamination and protecting public health. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.