pH‐Triggered Removal of Nitrogenous Organic Micropollutants from Water by Using Metal‐Organic Polyhedra

Water pollution threatens human and environmental health worldwide. Thus, there is a pressing need for new approaches to water purification. Herein, we report a novel supramolecular strategy based on the use of a metal‐organic polyhedron (MOP) as a capture agent to remove nitrogenous organic micropollutants from water, even at very low concentrations (ppm), based exclusively on coordination chemistry at the external surface of the MOP. Specifically, we exploit the exohedral coordination positions of RhII‐MOP to coordinatively sequester pollutants bearing N‐donor atoms in aqueous solution, and then harness their exposed surface carboxyl groups to control their aqueous solubility through acid/base reactions. We validated this approach for removal of benzotriazole, benzothiazole, isoquinoline, and 1‐napthylamine from water. MOPping up micropollutants: A new pH‐triggered pollutant‐removal methodology that uses water‐soluble metal‐organic polyhedra (MOPs) as coordinative capturing agents removes nitrogenous organic micropollutants from water. The exohedral coordination positions in the MOP structure are harnessed to coordinatively sequester the coordinating pollutants, while the exposed surface carboxyl groups are used to control their solubility in water through acid/base reactions. Benzotriazole (BT), benzothiazole (BTZ), 1‐napthylamine (NA) and isoquinoline (IQ) were selected to validate this methodology.