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The self‐assembly of the π‐conjugated 1,4‐di(1H‐imidazol‐1‐yl)benzene (dib) and 4,4′‐di(1H‐imidazol‐1‐yl)‐1,1′‐biphenyl (dibp) ligands together with 4′‐(3,4‐ dicarboxylphenyloxy)‐4‐biphenylcarboxylic acid (H3L) reacts with metal Zn (II) salts to construct two new coordination polymers (CPs), namely [Zn (dib)(HL)(H2O)] (1) and [Zn (dibp)(HL)] (2). Fluorescence measurements reveal that 1 and 2 could display a highly sensitive fluorescence response toward Hg2+ and nitrofurazone (NFZ). Fluorescence investigations suggest that 1 and 2 are promising multi‐responsive sensing materials for detecting Hg2+ and NFZ through fluorescence quenching (turn‐off). The limits of detection toward Hg2+ ions are 0.221 μM and 0.124 μM, while the limits of detection toward NFZ are 0.757 μM and 0.960 for 1 and 2, respectively. Interestingly, these Hg2+ and NFZ selective sensing processes can even be completed by the reusable CPs detected by the naked eyes. Hirshfeld surfaces and fingerprint plots are extensively used to investigate intermolecular interactions, which play a crucial role in creating diverse supramolecular designs that can be compared. [ABSTRACT FROM AUTHOR]

Coordination polymers (CPs) are an assorted class of coordination complexes that are gaining attention for the safe and sustainable removal of organic dyes from wastewater discharge by either adsorption or photocatalytic degradation. Herein, three different coordination polymers with compositions [Ni(HL)(H2O)2·1.9H2O] (1), [Mn3(HL)(L)(μ3-OH)(H2O)(phen)2·2H2O] (2), and [Cd(HL)4(H2O)]·H2O (3) (H3L = 2-(3,5-dicarboxyphenyl)-6-carboxybenzimidazole; phen = 1,10-phenanthroline) have been synthesized and characterized spectroscopically and by single crystal X-ray diffraction. Single crystal X-ray diffraction results indicated that 1 forms a 2D layer-like framework, while 2 exhibits a 3-connected net with the Schläfli symbol of (44.6), and 3 displays a 3D supramolecular network in which two adjacent 2D layers are held by π···π interactions. All three compounds have been used as photocatalysts to catalyze the photodegradation of antibiotic dinitrozole (DTZ) and rhodamine B (RhB). The photocatalytic results suggested that the Mn-based CP 2 exhibited better photodecomposition of DTZ (91.1%) and RhB (95.0%) than the other two CPs in the time span of 45 min. The observed photocatalytic mechanisms have been addressed using Hirshfeld surface analyses. [ABSTRACT FROM AUTHOR]

A new 2D coordination polymer, namely{[Cd2(BDC)2(bmb)2]·H2O}n (1) (H2BDC = 1,4-benzenedicarboxylic acid and bmb = 1,4-bis(2-methyl-1H-imidazol-1-yl)butane), has been prepared and full characterized. Coordination polymer 1 has 2D layer, which was further extended into 3D supramolecular motif through the π–π packing interactions. Coordination polymer 1 illustrated effectively photocatalytic performance to the disintegration of dyes Rhodamine B (Rh B), methyl orange (MO) and methylene blue (MB). Coordination polymer 1 can remove the dye MB with 90.37% after 100 min under simulated UV light and its catalytic feature conforms to the first order kinetics model. In addition, the possible mechanism of the catalytic degradation toward MB was suggested through the trapping experiments and LC–MS methods. [ABSTRACT FROM AUTHOR]

Developing a fast and sensitive method for the detection of 2,4,6-trinitrophenol (TNP) or Cr2O72- in aqueous solution has received great attention. In this work, a regenerable fluorescent coordination polymer [Zn(L)(H2L)]n (1) has been successfully constructed using a novel Schiff base ligand N'-[(E)-(3,5-dibromo-2-hydroxyphenyl)methylene]isonicotinohydrazide(H2L) and exploited as a dual detection probe for the selective sensing of Cr2O72- and TNP in water media. Competitive fluorometric experiments involving mixtures of anions or nitro compounds demonstrated 1 as an efficient and selective sensor for both Cr2O72- and TNP. The limits of detection for Cr2O72- and 2,4,6-trinitrophenol in aqueous solutions were found to be 11.4 and 1.19 μM, respectively. Moreover, 1 can detect TNP and Cr2O72- in real water samples. All these features clearly demonstrate its great potential of practical TNP and Cr2O72- detection in water media for public safety and security. [ABSTRACT FROM AUTHOR]

• A new Zn(II) coordination polymer (CP) synthesized using mixed ligand strategy • The CP was characterized using different physico-chemical techniques • The CP used as luminescent sensor to detect antibiotics • The CP used as photocatalyst for photodegradation of dyes Coordination polymers (CPs) are assorted class of multidimensional materials that could be deployed as sensors and photocatalysts against the photodegradation of aromatic dyes existing in the waste-water discharge. Herein, a new Zn(II)-based coordination polymer (CP) [Zn(dsn)(4,4'-bipy) 0.5 ] (1) has been synthesized by reacting Schiff base ligand 3,5-dibromosalicylaldehyde nicotinoylhydrazone (dsn) and 4,4′-bipyridine (4,4'-bipy) with Zn(NO 3) 2 ·6H 2 O and characterized using elemental analysis, FTIR, TGA, powder X-ray diffraction and single crystal X-ray diffraction techniques. The single crystal X-ray diffraction studies revealed tetragonal pyramidal geometry around Zn(II) and the architecture of 1 is stabilized by π···π interactions operating between pyridine ring of dsn and 4,4'-bipy. Also, other weak non-conventional weak interactions provide stability and engender supramolecular three dimensional framework in 1. The CP has been used as fluorescent sensor to detect antibiotics and exhibits selective sensing of secnidazole (SIZ) with limit of detection (LOD) 8.59 × 10−7 M. This showcase of 1 can act as an efficient and selective sensor for SIZ even in presence of other antibiotics. Also, the CP has been used as photocatalyst for photodegradation of Rhodamine B (Rh B) and degrades 80% of Rh B in 100 min. The plausible mechanism employing which CP 1 executed sensing of secnidazole (SIZ) and photocatalysis of Rh B have been explained with aid of theoretical calculations. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] A new 1D coordination polymer, [Zn(dsn)(HO 2 CCH 3)] n (1), has been synthesized by reacting the Schiff base ligand 3,5-dibromosalicylaldehyde nicotinoylhydrazone (H 2 dsn) with Zn(O 2 CCH 3) 2 ·6H 2 O. The polymer has been characterized using FTIR spectroscopy and single crystal X-ray diffraction analysis. The single crystal X-ray analysis reveals that the immediate geometry around the Zn(II) ion is five-coordinate, that is satisfied by a pyridyl nitrogen atom of one dsn ligand, the imine-N, carbonyl-O and phenoxo-O atoms of the other dsn ligand, as well as the acetate oxygen atom, which generate a trigonal bipyramidal geometry. Furthermore, the dsn ligand coordinated by the pyridyl nitrogen atom also coordinates to another Zn(II) ion by its imine-N, carbonyl-O and phenoxo-O atoms to generate a zig-zag lD polymer chain. The 1D chain is held by weak non-conventional interactions in the solid state to engender a 2D supramolecular layer. The photoluminescent (PL) property of 1 has been investigated and the polymer has been exploited as a sensitive and selective fluorescent sensor to detect metronidazole (MDZ) with limit of detection (LOD) of 9.39 × 10−7 M amongst a variety of related antibiotics. Also, 1 has been used as a photocatalyst and displays excellent photocatalytic degradation of methylene blue (MB), decomposing 86.3% in 100 min under UV light irradiation. The plausible mechanisms which polymer 1 executed for the sensing of MDZ and photodegradation of MB have been explained with the aid of theoretical calculations. [ABSTRACT FROM AUTHOR]

• Two different structural frameworks have been designed and synthesized. • Photocatalytic studies show both of them have efficient degradation activity of organic dye methyl violet. • The possible mechanism of the photocatalytic property has been suggested. Two new CoII-based coordination polymers tuned by the flexible "V"-shaped 3,3ˊ-(1,2-phenylenebis(methyleneoxy)) dibenzoic acid (H 2 L) and different N -donor spacers, namely, [Co(L)(bib)] n (1) and [Co 2 (L) 2 (phen) 2 (H 2 O) 2 ·H 2 O] n (2) (bib = 1,4-bis(1-imidazoly)benzene and phen = 1,10-phenanthroline) have been prepared. In 1, the CoII centers are linked by L to form a Co–L chain, which is further extended into a 2D wave-like layer by bib linkers. In 2 , the L linker connected the adjacent Co(II) centers into 1D chain, which is joined into a 3D supramolecular structure through H-bonded and π–π stacking interactions. The diverse networks of 1–2 demonstrate that the steric hindrance effect may show significant effect on the final structures. In addition, the title complexes exhibit photocatalytic activity for dye methyl violet (MV) degradation under UV light. [ABSTRACT FROM AUTHOR]

A 2D luminescent coordination polymer exhibits impressive aqueous stability, strong luminescence and recyclable properties, making it a promising candidate as a dual-functional luminescence sensor for selective detection of TNP and Cr 2 O 7 2– ion in water media. • 1 works as a selective and sensitive sensor for aqueous detection of TNP. • 1 works as a selective and sensitive sensor for aqueous detection Cr 2 O 7 2–. • The sensing ability of 1 could be easily regenerated. We report the solvothermal synthesis and fluorescent property of a novel luminescent coordination polymer (LCP) by choosing a new coplanar ligand, 2-(4-(3,5-dicarboxylphenoxy)phenyl) benzimidazole-5-carboylic acid (L). Single-crystal X-ray diffraction analysis reveals that the obtained LCP is formulated as {Cd(L 2 } n (1) and features a 2D uninodal 4-connected sql/Shubnikov tetragonal plane net with {44.62} topology. Fluorescence experiments suggest that 1 could work as highly sensitive and selective probe for both Cr 2 O 7 2– and 2,4,6-trinitrophenol in water medium, resisting interferences from a variety of competitive anions or nitroaromatic compounds. The limits of detection for Cr 2 O 7 2– and TNP in aqueous solutions were calculated to be 0.128 and 0.089 μM, respectively. Just by a simple method, the fluorescent sensing ability of 1 could be regenerated. [ABSTRACT FROM AUTHOR]

The photocatalytic experimental results demonstrated that both 1 and 2 displayed efficient photocatalytic performances to degrade MV under UV irradiation. The mechanism using which these CPs executed photocatalytic behaviour has been proposed. • Through design, two new coordination complexes were obtained. • The photocatalytic results demonstrated that both of them displayed efficient performances to degrade MV. • The mechanism of photocatalytic behaviour has been proposed. The assembly of 3,3ˊ-(1,2-phenylenebis(methyleneoxy)) dibenzoic acid (H 2 L) with CoII/CuII salts in presence of 1,1′-(1,4-butanediyl)bis(imidazole) (bbi) ancillary ligand generated two new coordination polymers (CPs) with formula [Co(L)(bbi)] n (1) and [Cu 3 (μ 2 -OH) 2 (L) 2 (bbi)] n (2). The crystallographic studies revealed that 1 exhibits 2D layer structure, while 2 displays 1D chain. The photocatalytic activities of title materials have been tested for the degradation of a model organic dye methyl violet (MV). The photocatalytic experimental results demonstrated that both 1 and 2 displayed efficient photocatalytic performances to degrade MV under UV irradiation. The mechanisms of these CPs for photocatalytic behaviour have been proposed. [ABSTRACT FROM AUTHOR]