A Versatile Anionic Cd(II)-Based Metal–Organic Framework for CO2 Capture and Nitroaromatic Explosives Detection

A three-dimensional (3D) anionic Cd-MOF, namely, (Me2NH2)2­[Cd­(PTC)]­·2H2O, assembled by a Cd­(II) salt and a planar aromatic core ligand containing tetracarboxylate groups (H4PTC = pyrene-1,3,6,8-tetracarboxylic acid), has been successfully constructed through a solvothermal method. In the structure of the fabricated Cd-PTC, each Cd­(II) center links four carboxyl groups, and each PTC4– ligand connects four Cd­(II) ions through the deprotonated carboxylate groups in bidentate chelating style, generating a 3D network with one-dimensional rhombic channels. This topology was considered to be a 3D (4,4)-connected pts net. Gas sorption measurements reveal that desolvated Cd-PTC has a strong interaction with CO2 and displays highly selective CO2 capture between the mixed gases CO2/CH4 and CO2/N2. Meanwhile, luminescent studies reveal that Cd-PTC can detect nitroaromatic explosives, especially exhibiting significant sensitivity for 2,4,6-trinitrophenol in DMF solvent.