Heavy‐Metal Ions Removal and Iodine Capture by Terpyridine Covalent Organic Frameworks

Abstract Porous materials are excellent candidates for water remediation in environmental issues. However, it is still a key challenge to design efficient adsorbents for rapid water purification from various heavy metal ions‐contaminated wastewater in one step. Here, two robust nitrogen‐rich covalent organic frameworks (COFs) bearing terpyridine units on the pore walls by a “bottom‐up” strategy are reported. Benefitting from the strong chelation interaction between the terpyridine units and various heavy metal ions, these two terpyridine COFs show excellent removal efficiency and capability for Pb 2+ , Hg 2+ , Cu 2+ , Ag + , Cd 2+ , Ni 2+ , and Cr 3+ from water. These COFs are shown to remove such heavy metal ions with >90% of contents at one time after the aqueous metal ions mixture is passed through the COF filter. The nitrogen‐rich features of the COFs also endow them with the capability of capturing iodine vapors, offering the terpyridine COFs the potential for environmental remediation applications.