In this work, a new type of zinc(II) coordination polymer {[Zn(HIDC)(BBM)0.5]·H2O}
n
(Zn-CP) was synthesized using 4,5-imidazoledicarboxylic acid (H3IDC) and 2,2-(1,4-butanediyl)bis-1,3-benzimidazole (BBM) under hydrothermal conditions. Its structure has been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction analysis. The Zn(II) ion is linked by the HIDC2− ligand to form a zigzag chain by chelating and bridging, and then linked by BBM to form a layered network structure. Adjacent layers are further connected by hydrogen bond interaction to form a 3-D supramolecular framework. The solid-state fluorescence performance of Zn-CP shows that compared with free H3IDC ligand, its fluorescence intensity is significantly enhanced.
Two new silver(I) complexes, formulated as [Ag2(L1)2](picrate)2 (1), {[Ag2(L2)2(terephthalate)](C2H5OH)3(H2O)}n (2) (L1 = 1,3‐bis(2‐benzimidazyl)benzene, L2 = 1,3‐bis(1‐methylbenzimidazol‐2‐yl)‐2‐thiapropane), were synthesized and characterized by X‐ray crystallography, elemental analysis, infrared, and UV–Vis spectroscopy. The crystal analysis results showed that the complexes exhibited different structures: binuclear for 1 and one‐dimensional polymeric for 2. Their Ag(I) centers displayed different coordination geometric structures: two‐coordinated linear in 1, whereas four‐coordinated distorted tetrahedron in 2. The electrochemical sensing performance of Ag(I) complexes modified carbon paste electrode (CPE‐1 and CPE‐2) toward hydrogen peroxide (H2O2) was evaluated by chronoamperometry in 0.2 M phosphate buffer saline (pH = 6) at −0.2 V. The CPE‐1 was found to have a wide linear response from 1.0 × 10−5 to 4.0 × 10−3 M, lower detection limit of 1.73 μM, excellent anti‐interference ability, and stability. The CPE‐2 does not have recognition properties for H2O2, which may be due to the large steric hindrance around Ag(I) centers that is not easy to combine with H2O2 to form a catalytic transition state. The above studies proved that Ag(I) complexes can be used as effective components of electrode materials for the electrochemical recognition of H2O2.
Under different solvent systems, the reaction of Cd(NO 3 ) 2 Á4H 2 O with 2-pmethoxyphenyl-1H-imidazole-4,5-dicarboxylic acid (p-H 3 MOPhIDC) ligand produce two new Cd-MOFs, [Cd(p-HMOPhIDC)(C 2 H 5 OH)] n (1) and [Cd 2 (p-HMOPhIDC) 2 (Py)(C 2 H 5 OH)] n (2). Structural analysis shows that although the two Cd-MOFs have the same six-coordinated distorted octahedron geometry of the Cd(II) centers and the similar framework structure, they have different coordinated polymerization unit symmetry and internal environment in the channels. Among them, the polymerization unit in the channel of Cd-MOFs 1 is centrosymmetric, while the polymerization unit in the channel of Cd-MOFs 2 is asymmetric. Compared with the free p-H 3 MOPhIDC ligand, the fluorescence peaks of the two Cd-MOFs in the solid-state have undergone a slightly red shiftand enhancement. This is due to the increased rigidity of the ligand after the coordination of the metal ions with the ligand, which reduces the energy loss of thermal vibration. The fluorescence enhancement of Cd-MOFs 1 is greater than that of 2, which is related to the symmetry of the coordination polymerization units in the two Cd-MOFs channels. In addition, Cd-MOFs 2 can highly sensitive sense 2,4-dinitrotoluen (DNP) and 2,4,6-trinitrophenol (TNP) through luminescence quenching effect, whereas 1 cannot. This result is due to the difference in the environment within their channels.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.