Scalable hydrogen-bonded organic framework-based membranes for efficient ultra-high PFOA adsorption.

Per- and polyfluoroalkyl substances (PFAS), such as perfluorooctanoic acid (PFOA), pose severe environmental and health risks owing to their persistence and widespread contamination of water resources. Their effective removal from water, however, remains challenging due to the difficulty of simultaneously achieving high removal efficiency, high adsorption capacity, and scalable processability. Here, we address this challenge by integrating high-capacity molecular adsorption directly into a scalable membrane architecture. We report a composite membrane formed by the in situ growth of a hydrogen-bonded organic framework (HOF-21m) with exceptional PFAS affinity on a cellulose substrate. The resulting membrane simultaneously delivers 99.9% PFOA rejection and high water permeance (86.3 L m-2 h-1 bar-1), while exhibiting an outstanding PFOA adsorption capacity of (6.57 ± 0.38) × 103 mg g-1, enabled by synergistic multi-site interactions within the HOF framework. Importantly, the use of inexpensive ligands and mild synthesis conditions allows roll-to-roll fabrication of large-area continuous membranes (0.6 m × 10 m), demonstrating clear scalability. These findings establish HOF-based membranes as a practical platform for high-performance PFAS removal.