A luminescent Cd(II)-MOF as recyclable bi-responsive sensor for detecting TNP and iron(III)/silver(I) with high selectivity and sensitivity.

A new three dimensional framework {[Cd 2 (BPDPE) 2 (chdc) 2 (H 2 O) 2 ]·4H 2 O} n ( 1 ) (BPDPE = 4,4′-bis(pyridyl)diphenyl ether H 2 chdc = 1,4-cyclohexanedicarboxylic acid) has been successfully synthesized and characterized. In this complex, the chdc 2− adopts tran - configuration, was linked by three types of Cd ions to form wave-like 2D layer with hexagonal grids. The 2D layers are linked by meso-helical chains Cd n (BPDPE) n to form a 3D framework. It is surprised find that complex 1 can highly sensitive sense 2, 4, 6-trinitrophenol (TNP) through luminescence quenching effect, the quenching constant is up to 2.794 × 10 5 M −1 . In addition, complex 1 also presents highly sensitive fluorescent sensor for detecting Fe 3+ and Ag + ions. The quenching constants are 2.893 × 10 4 M −1 and 1.483 × 10 4 M −1 . Furthermore, the quenching mechanisms of complex 1 as multifunctional sensor have been studied. [ABSTRACT FROM AUTHOR]