Electrochemical advanced oxidation of per- and polyfluoroalkyl substances (PFASs): Development, challenges and perspectives

Abstract

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been globally distributed since 1940, resulting in their widespread existence in natural environments. This is due to the remarkable stability of carbon–fluorine bonds, which are difficult to degrade chemically in a natural setting. PFASs accumulate in the human body through daily consumption of water and food, which can lead to potential health effects such as immune, metabolic, and neurodevelopmental effects. As a result, there is a growing global concern regarding PFAS remediation, given their toxicity and bio-accumulative properties in recent years. Electrochemical advanced oxidation processes (EAOPs) have been developed for the remediation of PFASs and have been applied in wastewater treatment. In these processes, a highly powerful oxidizing agent, hydroxyl radical (()OH), is generated electrochemically in solution, which can oxidize organic contaminants. EAOPs have become an environmentally friendly and effective treatment process for destroying PFASs. However, their slow reaction rate, poor performance stability, high energy consumption, and electrode erosion hinder their commercialization for water treatment. This paper provides a comprehensive overview of state-of-the-art anode materials and their corresponding degradation efficiency of PFASs through electrochemical remediation, along with future recommendations. A worldwide perspective on the fundamentals and experimental setups is provided, examining, and discussing different anode electrodes, as well as the challenges of EAOPs for PFAS remediation.