An unusual (4,4)-connected 3D porous cadmium metal–organic framework as a luminescent sensor for detection of nitrobenzene

Abstract

The metal–organic framework {[Cd₂(obtz)₂(btec)(H₂O)₂]·3.5H₂O}_n (1) was synthesized and characterized (obtz = 1,2-bis(1,2,4-triazole-1-ylmethyl)benzene, btec = 1,2,4,5-benzenetetracarboxylate). 1 shows an unusual (4,4)-connected 3D porous network with the Schläfli symbol of (6²·8 × 10³)₂(6³ × 10³). 1 exhibits a strong blue emission band maxima at 421 nm and a shoulder peak at 464 nm in the solid state. The luminescent properties of 1 dispersed in various kinds of solvents were investigated in detail. The high quenching efficiency of 1 is up to 98.2% at 160 ppm NBZ. 1 displays highly selectivity, sensitivity and recyclability in the detection of nitrobenzene.