IMPACT: Innovative (nano)Materials and processes for advanced catalytic technologies to degrade PFOA in water.

We hereby report the development of a novel electrochemical method to degrade perfluorooctanoic acid (CFCOOH, PFOA). At the center of the approach are bimetallic Pd-Ru nano-catalyst materials called IMPACT: Innovative (nano)Materials and Processes for Advanced Catalytic Technologies. IMPACT uses flavonoid-sequestered Pd-Ru, allowing the development of specialized electrodes with tunable properties to sequentially degrade PFOA in wastewater samples into a sustainable byproduct via an indirect electrochemical method. Electron transfers at RuOH species stabilize the Pd component of the nano-catalysts, enabling the degradation process via PFOA deprotonation, chain shortening, decarboxylation, hydrolysis, fluoride elimination, and CF flake-off mechanism. IMPACT enabled the observation of redox peaks at -0.26 V and 0.56 V for the first time, with accompanying reduction peaks at -0.5V and 0.29 V, respectively. These redox peaks, which correlated with the concentrations of PFOA (20, 50, 100, 200, and 400. mg L), were verified and confirmed using electrochemical simulations. Control experiments did not show degradation of PFOA in the absence of Pd-Ru nano-catalyst. The degradation in wastewater was obtained within 3 h with an efficiency of 98.5%. The electrochemical degradation products of PFOA were identified using High-resolution desalting paper spray mass spectrometry (DPS-MS) and collision-induced dissociation (CID) analysis. The results yielded CFCOOH, CFCOOH, and CFOH with dissociation losses of CFO or CO. IMPACT introduces a novel nano-catalyst with high efficiency and a reliable capability that defluorinates strong C-F bonds that are components of recalcitrant organics in myriad environmental matrices.