Design and synthesis of MOF-1 and Tb@ MOF-1 as fluorescent probes for recognizing trace amounts of Cr₂O₇^2- and S₂O₈^2- ions

A new fluorescent probe metal-organic framework (MOF) materials formulated as [Cd(PLIA)(TIB)](n) (MOF-1) was successfully obtained adopting 5-((4-pyridyl)methoxy)-isophthalic acid (H(2)PLIA) and 1,3,5-tris(1-imidazolyl)-benzene (TIB). MOF-1 possesses 2D networks with an ideal 1D tunnel, and the 1D tunnel is spaced and driven by the flexible triangle PLIA(2-) and rigid triangle TIB ligands. Employing the advantage of MOF-1 channel easy doping, efficient luminescent probe Tb@MOF-1 was also constructed using a coordinated post-synthetic modification strategy. MOF-1 and Tb@MOF-1 were fully characterized in detail, and the two probe materials have the same structural feature. The fluorescence recognition performance was investigated in detail, revealing a capability of MOF-1 for sensing Cr2O72-, Tb@MOF-1 for identifying S2O82- anion. Herein, the fabricated fluorescent probes exhibit fascinating features, such as fast response time, remarkable stability, excellent selectivity, and high sensitivity. The possible fluorescence recognition mechanism of Cr2O72- and S2O82- by MOF-1 and Tb@MOF-1 has been investigated, and the difference in the mechanism may be related to Tb3+ ion doping. CCDC: 2227197, MOF-1.