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As regulatory standards for per- and polyfluoroalkyl substances (PFAS) become increasingly stringent, innovative water treatment technologies are urgently demanded for effective PFAS removal. Reported sorbents often exhibit limited affinity for PFAS and are frequently hindered by competitive background substances. Recently, fluorinated sorbents (abbreviated as fluorosorbents) have emerged as a potent solution by leveraging fluorine–fluorine (F···F) interactions to enhance selectivity and efficiency in PFAS removal. This review delves into the designs and applications of fluorosorbents, emphasizing how F···F interactions improve PFAS binding affinity. Specifically, the existence of F···F interactions results in removal efficiencies orders of magnitude higher than other counterpart sorbents, particularly under competitive conditions. Furthermore, we provide a detailed analysis of the fundamental principles underlying F···F interactions and elucidate their synergistic effects with other sorption forces, which contribute to the enhanced efficacy and selectivity. Subsequently, we examine various fluorosorbents and their synthesis and fluorination techniques, underscore the importance of accurately characterizing F···F interactions through advanced analytical methods, and emphasize the significance of this interaction in developing selective sorbents. Finally, we discuss challenges and opportunities associated with employing advanced techniques to guide the design of selective sorbents and advocate for further research in the development of sustainable and cost-effective treatment technologies leveraging F···F interactions.

Current research on heterogeneous advanced oxidation processes (HAOPs) predominantly emphasizes catalyst iteration and innovation. Significant efforts have been made to regulate the electron structure and optimize the electron distribution, thereby increasing the catalytic activity. However, this focus often overshadows an equally essential aspect of HAOPs: the adsorption effect. Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts. The efficacy of these interactions is influenced by a variety of physicochemical properties, including surface chemistry and pore sizes, which determine the affinities between contaminants and material surfaces. This disparity in affinity is pivotal because it underpins the selective removal of contaminants, especially in complex waste streams containing diverse contaminants and competing matrices. Consequently, understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving process efficiency but also for enhancing the selectivity of contaminant removal. Herein, we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs. Such interactions dictate the overall performance of the treatment processes by balancing the adsorption, reaction, and desorption rates on the catalyst surfaces. Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practicality in water treatment and wastewater decontamination. Overall, we propose that revisiting adsorption-driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.