Anthracene-Based Lanthanide Coordination Polymer: Structure, Luminescence, and Detections of UO22+, PO43–, and 2-Thiazolidinethione-4-carboxylic Acid in Water

By the solvothermal assembly of Gd3+ and 5,5′-(anthracene-9,10-diyl)diisophthalic acid (H4adip), an anthracene-based lanthanide coordination polymer (CP), [Gd2(adip)(H2adip)(NMP)2]·DMF·3H2O (1; NMP = N-methylpyrrolidone; DMF = N,N-dimethylformamide), has been prepared. It possesses a 3D framework and a strong ligand-based blue emission. 1 could be applied as a multifunctional chemical sensor for UO22+, PO43–, and 2-thiazolidinethione-4-carboxylic acid (TTCA) with excellent selectivity, sensitivity, and anti-interference. In the 0–20 μM concentration range of UO22+, the quenching constant (KSV) is 4.05 × 104 M–1 with a detection limit of 1.42 μM. Fluorescence enhancement was observed when PO43– was added to the 1–H2O suspension. The slope of the linear relationship between the PO43– concentration in the 0–35 μM concentration range and I/I0 is 3.70 × 104 M–1 with a detection limit of 1.55 μM. When the TTCA concentration is lower than 20 μM, the fluorescence quenching constant KSV is 1.77 × 104 M–1 with a detection limit of 3.25 μM, which approaches the values reported of the best CP-based sensing materials for TTCA up to now. Moreover, the fluorescence quenching or enhancement mechanism was also investigated.