A Robust Luminescent Tb(III)-MOF with Lewis Basic Pyridyl Sites for the Highly Sensitive Detection of Metal Ions and Small Molecules

A new luminescent terbium–metal–organic
framework [Tb3(L)2(HCOO)­(H2O)5]·DMF·4H2O (1) (H4L = 4,4′-(pyridine-3,5-diyl)­diisophthalic acid) has
been successfully assembled by Tb3+ ions and an undeveloped
pyridyl-tetracarboxylate. Compound 1 exhibits a 3D porous
(3,8)-connected (4.52)2(42.512.66.75.83) topological framework
with fascinating 1D open hydrophilic channels decorated by uncoordinated
Lewis basic pyridyl nitrogen atoms. In particular, the Tb-MOF (1) can detect Cu2+ ions with high selectivity and
sensitivity, and its luminescence is nearly entirely quenched in N,N-dimethylformamide (DMF) solution and
biological system. In addition, 1 still has high detection
for the trace content of nitromethane with 70 ppm, which suggests
that 1 is a promising example of dual functional materials
with sensing copper ions and nitromethane.