Acetonitrile sensing property of a microporous Co(II) metal-organic framework based on azobenzenetetracarboxylate ligand

A new Co(II)-MOF [NH2(CH3)2][Co1.5(abtc)]·H2O (1) (H4abtc: 3,3′,5,5′‑azobenzenetetracarboxylic acid) has been solvothermally synthesized and characterized. Complex 1 is a three-dimensional {Co3}-based framework with one-dimensional channels bridged by the μ2-bridging abtc ligand, resulting in a (4, 8)-connected topology. Luminescent studies reveal that complex 1 shows weak emission in solid state at room temperature, but the emission intensities have greatly enhanced in both liquid suspensions and solid state after immersion in acetonitrile solvent.