Solvo‐thermal Preparation and Characterization of Two CdII Coordination Polymers Constructed From 2,6‐(1,2,4‐Triazole‐4‐yl)pyridine and 5‐R‐Isophthalic Acid (R = Nitro, Sulfo)

Abstract

Under the solvo‐thermal conditions, two novel CdII mixed‐ligand coordination materials with 2,6‐(1,2,4‐triazole‐4‐yl)pyridine(L1) and aromatic poly‐carboxylic acid co‐ligands such as 5‐R‐isophthalic acid (R = nitro, sulfo), namely [Cd(L1)(NO2‐BDC)(H2O)2]·2H2O (1) and [Cd(L1)(HSIP)(H2O)]·4H2O (2) (NO2‐H2BDC = 5‐nitroisophthalic acid, H3SIP = 5‐sulfobenzene ‐isophthalic acid) were successfully prepared. These CdII mixed‐ligand coordination polymers 1–2 have been measured by crystal X‐ray analysis, FT‐IR spectra and powder X‐ray diffraction analyses. In 1, these seven‐coordinate CdII atoms (Cd1) are inter‐linked by didentate 5‐nitroisophthalic acid ligands forming 1D chain structures. In 2, these L1 and partially de‐pronated HSIP2– are inter‐linked by central CdII centers and are arranged into the unique 2D micro‐porous metal‐organic framework of 2. Side view of 2, it is noted that numerous oxygen atoms of un‐coordinated carboxylate groups and coordinated SO3 groups protrude out and decorate the 2D framework of 2. PXRD patterns of 1 and 2 sample is tested, which is consistent with the simulated PXRD diffraction pattern. Photoluminescence studies show that 2 is highly selective and sensitive to trace elements of Eu3+ with excellent Ksv value (7.86 × 104 m–1) and low detection limit (5.56 × 10–2 mM), which also provides a convenient method and platform for real‐time detection of Eu3+.