Understanding the Behavior of Perfluorocarboxylic Acids at Aqueous InterfacesJenée D. Cyran

Per- and polyfluoroalkyl substances (PFAS) is a prevalent persistent organic pollutant with widespread distribution in the environment and atmosphere. Despite the importance, the fundamental principles of the underlying environmental processing and future outcomes of PFAS remains largely elusive. Here, we probed the behavior of various carbon chain lengths of PFAS and the nonfluorinated alkyl chain versions at the air/water interface utilizing vibrational sum frequency generation (SFG) spectroscopy. We observed an increase in the hydrogen bonded O-H region SFG signal with an increase in chain length for fluorinated alkyl chains, which is the opposite effect for the nonfluorinated chains. These results explore the distinctive physiochemical properties of PFAS with the goal of rational design of remediation techniques for PFAS from the environment.