Scalable Fluorinated Copper-Based Covalent Organic Frameworks for Coupled Ultratrace Perfluoroalkyl Substances Monitoring and Efficient Remediation

Abstract Per- and polyfluoroalkyl substances (PFAS) are persistent water contaminants that require both effective removal and reliable monitoring. However, these functions are typically performed separately, preventing real-time evaluation of treatment performance. Here we establish a cooperative host–guest-coupling principle, in which a single host–guest binding event simultaneously drives contaminant capture and modulates the Cu-centered redox process, thereby generating concentration-dependent electrochemical signals within a porous framework. Guided by this principle, we reported a scalable fluorinated copper-based covalent organic framework (F–Cu–COF) synthesized through an open-air one-pot strategy that enables gram-scale production while retaining high crystallinity and chemical stability. Fluorinated pore domains and redox-active Cu centers create a cooperative host–guest environment that promotes PFAS binding and enrichment with electrochemical signal generation. Consequently, F–Cu–COF achieves a detection limit of 5.2 pg L–1, an uptake capacity of 3824 mg g–1, and efficient flow-through removal. This work establishes host–guest coupling as a common molecular basis for linking electrochemical signal generation with contaminant capture in scalable porous materials, providing a general design strategy for multifunctional water-treatment platforms capable of integrated treatment verification.