A Metal-“Organic Cage” Framework for the Removal of Polycyclic Aromatic Hydrocarbons from Water

Metal-organic frameworks (MOFs) constructed with cavity-containing inherently porous organic cage linkers are rare. Among these, none have provided structural evidence of guest molecules being hosted inside the linkers. Such materials are highly desirable for trapping carcinogenic polycyclic aromatic hydrocarbons (PAHs) from water, which remains challenging with existing adsorbents. Herein, we present the first example of a metal-“organic cage” framework with structural evidence of guest molecules encapsulated within the organic cage linkers of the MOF. We utilize a triazole-equipped click cage (CC-1) and Ag(I)-triazole coordination to generate a dual-porous, water-stable, spontaneously resolved, chiral MOF (MOF-CC-1) in srs topology. MOF-CC-1 encapsulates a diverse range of PAHs within the cavity of CC-1, as confirmed structurally. Additionally, MOF-CC-1 demonstrates excellent adsorption capacity for PAHs from water. This study offers a promising strategy for developing highly efficient adsorbents to remove PAHs from water.