Cd Coordination Polymers Research Articles

Three robust Cd(II) coordination polymers as bifunctional luminescent probes for efficient detection of pefloxacin and Cr2O72- in water.

The accurate and rapid detection of antibiotics and heavy-metal-based toxic oxo-anions in water media employing coordination polymers (CPs) as luminescent probes has attracted a lot of attention. Three new Cd(II)-based ternary CPs derived from first-presented L ligands, including [Cd(DCTP)(L)(OH)]n (1), [Cd(TBTA)(L)(OH)]n (2), and [Cd(NPHT)(L)(H2O)]n (3) (L = 2-((1H-imidazol-1-yl)methyl)-5,6-dimethyl-1H-benzo[d]imidazole, H2DCTP = 2,5-dichloroterephthalic acid, H2TBTA = tetrabromoterephthalic acid and H2NPHT = 3-nitrophthalic acid), were successfully assembled and characterized. 1 and 2 show 2D hcb layers, which can be further extended into a 3D supramolecular framework via classic hydrogen bonding interactions. 3 features a 1D double chain that ultimately spreads into a 2D network through weak hydrogen bonding interactions. With the advantages of high stability and excellent luminescent properties, the three CPs display high sensitivity, selectivity, and good anti-interference for the sensing of pefloxacin (PEF) and Cr2O72- ions (LOD values toward PEF: 3.82 × 10-7 mol L-1 for 1, 4.06 × 10-7 mol L-1 for 2, and 1.36 × 10-8 mol L-1 for 3, and toward Cr2O72- ions: 5.97 × 10-7 mol L-1 for 1, 5.87 × 10-7 mol L-1 for 2, and 8.21 × 10-8 mol L-1 for 3). These CPs are the first examples of bifunctional luminescent sensors to detect PEF and Cr2O72- in aqueous solutions. The luminescence quenching mechanisms are explored in detail.

Fabrication, Crystal Structures, Catalytic, and Anti-Wear Performance of 3D Zinc(II) and Cadmium(II) Coordination Polymers Based on an Ether-Bridged Tetracarboxylate Ligand

Two 3D Zn(II) and Cd(II) coordination polymers, [Zn2(µ4-dppa)(µ-dpe)(µ-H2O)]n·nH2O (1) and [Cd2(µ8-dppa)(µ-dpe)(H2O)]n (2), have been constructed hydrothermally using 4-(3,5-dicarboxyphenoxy)phthalic acid (H4dppa), 1,2-di(4-pyridyl)ethylene (dpe), and zinc or cadmium chlorides. Both compounds feature 3D network structures. Their structure and topology, thermal stability, catalytic, and anti-wear properties were investigated. Particularly, excellent catalytic performance was displayed by zinc(II)-polymer 1 in the Knoevenagel condensation reaction at room temperature.

Three functional Cd(II) coordination polymers constructed by the thiazolothiazole extended viologen ligand

Expanding the π-conjugated structure of traditional viologens by incorporating thiazole units to the bipyridine skeleton has attracted more and more attention. In this work, a rigid thiazolothiazole extended viologen ligand (TTVP, 2,5-bis (pyridinium-4-yl) thiazolo [5,4-d] thiazole propionate) has been used to constitute three new functional Cd(II) coordination polymers (CPs), {[Cd(TTVP)0.5(HBTC)(H2O)2]·2H2O}n (1), {[Cd(TTVP)0.5(p-BDC)0.5(p-HBDC)(H2O)]·3H2O}n (2), {[Cd(TTVP)0.5(m-BDC)]}n (3) by introducing different benzenecarboxylic acids as auxiliary ligands (H3BTC = 1,3,5-benzenetricarboxylic acid; p-H2BDC = 1,4-benzenedicarboxylic acid; m-H2BDC = 1,3-benzenedicarboxylic acid). The crystal structures and photochromic capabilities of 1−3 are studied. Both compounds 1 and 2 own one-dimensional (1D) chain-like structure, while compound 3 owns two-dimensional (2D) layered structure. As expected, compounds 1−3 show reversible photochromism due to electron-transfer (ET). In addition, the photo-controlled luminescent properties and the potential application as inkless and erasable printing media are also explored.

A new coordination polymer of Cd(II) with 4-methyl-1,2,4-triazole-3-thiol ligand: synthesis, characterization, crystal structure, photoluminescence and DFT calculation

A new coordination polymer of Cd(II) with 4-methyl-1,2,4-triazole-3-thiol ligand: synthesis, characterization, crystal structure, photoluminescence and DFT calculation

Structural Characterization of a Porous 3D Cd(II) Coordination Polymer Based on 1,2,4-Triazole and 2-Nitro-4-Benzenedicarboxylic Acid

Structural Characterization of a Porous 3D Cd(II) Coordination Polymer Based on 1,2,4-Triazole and 2-Nitro-4-Benzenedicarboxylic Acid

Coordination-Driven Heterochiral Self-Assembly: Construction of Cd(II) Coordination Polymers with Sorption Behaviors for Iodine and Dyes.

A racemic bispyridyl ligand (L) was synthesized via a Schiff base condensation reaction. Four Cd(II) complexes, {[CdL2Cl2]·2DMF}n (1), [CdLI2]n (2), {[CdL2Br2]·4H2O}n (3), and {[CdL2(H2O)2](NO3)2·2CH3OH·8H2O}n (4), were synthesized and further characterized based on this ligand. Single-crystal structures show that the coordination-driven assembly of the bispyridyl ligand with Cd(II) salts bearing different counteranions can lead to multidimensional coordination polymers via a heterochiral self-discrimination process. Complex 1 exists as a one-dimensional (1D) looped chain polymer, and complex 2 exists as a 1D zigzag chain polymer. Complex 3 is a 2D grid coordination polymer, and complex 4 exists as a 3D framework polymer. Furthermore, the iodine sorption capacities of the four complexes were investigated in the solution of n-hexane and water as well as in the iodine steam. The dye sorption behaviors were investigated in water, which showed that complex 2 exhibited good adsorption for crystal violet (CV), while complex 4 had good adsorption capability toward direct yellow 4 (DY).

Two new luminescent Cd(II) coordination polymers displaying high sensitivity for norfloxacin

Two new ternary Cd(II) coordination polymers (CPs), namely, [Cd(DCTP)0.5(L)2(SO4)0.5]n (1) and [Cd(DCTP)(L)]n (2) (L = 2-(4-thiazolyl) -1H-benzimidazole; H2DCTP = 2,5-dichloroterephthalic acid), were successfully synthesized using the solvothermal method. 1 displays a 1D zigzag infinite chain, which can be further extended into the 2D network via classic hydrogen bonding interactions in a triclinic system (unit cell parameter: a = 9.251(2) Å, b = 11.194(3) Å, c = 12.865(3) Å. α = 105.362(2)°, β = 97.871(2)°, γ = 98.229(2)°). 2 is a (3,4)-connected 2D layer that is subsequently expanded into a 3D supramolecular framework through π···π stacking interactions in a triclinic system (a = 9.161(3) Å, b = 9.225(4) Å, c = 12.575(4) Å. α = 89.554(3)°, β = 69.446(3)°, γ = 68.858(4)°). Both CPs demonstrate exceptional stability in the wide pH range of 3−12. Furthermore, 1 and 2 can act as exceptional luminescent probes for the sensing of norfloxacin with low limits of detection (2.03 × 10−9 mol/L for 1 and 4.88 × 10−8 mol/L for 2) and remarkable anti-interference abilities. Moreover, the mechanisms of the luminescence quenching of CPs are investigated.

Series of Cadmium-Organic Frameworks Based on Mixed Flexible and Rigid Ligands: Single-Crystal-to-Single-Crystal Transformations, Sorption, and Luminescence Properties.

Here, we present a series of Cd(II) coordination polymers containing two types of ligands: sterically rigid terephthalate derivatives (bdc-NO22- and bdc-Br2-) and flexible bis(2-methylimidazolyl)propane (bmip). The combination of two types of ligands is used to obtain and characterize compounds by single crystal and powder X-ray diffraction, FT-IR, elemental analysis, and TGA. Guest exchange results in structural transformations. 2-fold interpenetrated 1·DMF and 2·DMF rapidly undergo to 4-fold interpenetrated 1·Et2O, 1·EtOH, and 1·H2O, or 2·Et2O, respectively. Also, changes in the coordinating numbers and length of the N,N'-donor bmip ligand were observed according to single crystal X-ray analysis. Activated guest-free compounds [Cd(bdc-NO2)(bmip)] (1) and [Cd(bdc-Br)(bmip)] (2) are shown to be porous with a BET surface area of 103 and 283 m2·g-1, respectively. Moreover, both compounds demonstrate gate-opening behavior of ethylene adsorption isotherms at low pressures (<1 bar) and highly selective adsorption of benzene over cyclohexane or lower alcohols. Also, both compounds demonstrate a strong dependence of the maximum of the photoluminescence emission on an excitation wavelength. As a result, the photoluminescence color changes from white to red and from blue to red through green and yellow for compounds 1 and 2, respectively, with excitation wavelength changing from 360 to 540 nm.

Two new Zn(II) and Cd(II) coordination polymers derived from 1,3,5-tris(3-carbonylphenyloxy)benzene and 4,4′-bis(imidazolyl)biphenyl ligands: Syntheses, structure and luminescent sensing of antibiotics

Two new coordination polymers with formulae [Zn(HL)(bb)]n (1) and [Cd(HL)(bb)]n (2) (H3L = 1,3,5-tris(3-carbonylphenyloxy)benzene and bb = 4,4′-bis(imidazolyl)biphenyl) have been synthesized solvothermally and structurally characterized by elemental analysis, IR, single crystal X-ray diffraction and thermal analyses. Single crystal X-ray diffraction studies reveal that compounds 1 and 2 show similar three-fold interpenetrating 4-connected 2D framework structure with the sql topological net and the Schläfli symbol of {44·62} and are further extended into 3D supramolecular network by inter-molecular hydrogen bonding. Compound 1 have been used as turn-off luminescent sensor and displayed sensitive and selective luminescence sensing for nitrofurazone antibiotic (NFZ) with Ksv of 0.87 × 103 M−1 and 1.98 ppm limit of detection (LOD). The plausible mechanistic pathway for the detrioration in the luminescent intensity of 1 in presence of antibiotics have been explained with the help of theoretical calculations. The calculations indicated that the decline in fluorescence intensity of 1 was accredited to the electron/energy transfer as well as weak interactions operating between 1 and antibiotic.

Synthesis and Fluorescence Sensing for Nitro Explosives and Pesticides of Two Cd-Coordination Polymers.

Two cadmium coordination polymers (CPs), {[Cd(zgt)(2,2'-bipy)(H2O)]·H2O}n (1) and {[Cd(zgt)(BPP)(H2O)]·H2O}n (2) (H2zgt = 5-methoxyresorcinic acid, 2,2'-bipy = 2,2'-bipyridine, and BPP = 1,3-bis(4-pyridyl)propane), were prepared by the hydrothermal method. The structures of CPs 1-2 were characterized by IR, TGA, X-ray powder diffraction, and elemental analysis. The single-crystal structure analysis shows that CP 1 is a typical 1D chain structure and CP 2 belongs to a 2D layered structure. Based on the excellent luminescence properties of CP 1 and 2, fluorescence sensing experiments were carried out for explosives and pesticides. The results of the explosion sensing experiment showed that CP 1 and 2 had an excellent fluorescence quenching effect on PNBA (p-nitrobenzoic acid) and TNP (2,4,6-trinitrophenol), respectively, and the detection limits were 3.28 and 11.4 nM, respectively. Interestingly, both CP 1 and 2 showed good fluorescence quenching against the pesticide fluridine (Flu), and CP 1 had a lower detection limit and was more sensitive. In addition, the fluorescence quenching mechanism was discussed in detail by the UV absorption spectrum and density functional theory. In order to explore its practical application, the content of Flu in water samples was detected by a labeling recovery method.

A three-component Cd(II) coordination polymer for efficient multi-media iodine capture

This work reports a simple and affordable method for synthesizing a three-component Cd(II) coordination polymer (CP) consisting of a flexible polyether-based dicarboxylate and a rigid bifunctional linker with nitrogen donor atoms for the capture of iodine from both vapor and an organic medium. A Cd(II) CP, {[Cd(toua)(4,4′-bpy)]·2H2O}n (1), was synthesized by a one pot self-assembly reaction of Cd(OAc)2·2H2O, H2toua and 4,4′-bpy in methanol at room temperature, where H2toua = 3,6,9-trioxaundecanedioic acid and 4,4′-bpy = 4,4′-bipyridine. It was characterized by elemental analysis, spectroscopic (FTIR and UV–visible spectroscopy), and microscopic techniques (SEM and TEM) techniques. 1 was found to be suitable for iodine capture both in the organic phase and vapor phase. It had significant uptakes in the vapor phase (1.78 g/g) and in hexane (623 mg/g). It also showed 100% release in ethyl acetate in 2 h, as monitored by UV–visible spectroscopy. Furthermore, the interaction of 1 and I2 was investigated by FTIR and UV–visible spectroscopy, thermogravimetric analysis, SEM and EDX analysis, and kinetic studies.

Synthesis and characterization of new 2D coordination polymers based on mixed 1,1-cyclopentanediacetate and 1,2-bis((1H-imidazol-1-yl)methyl)benzene linkers

New three Co(II), Zn(II) and Cd(II) coordination polymers (CPs), [Co(µ-cpda)(µ-obimb)]n (1), [Zn(µ-cpda)(µ-obimb)]n (2) and [Cd(µ-cpda)(µ-obimb)]n (3) [H2cpda: 1,1-cyclopentanediacetic acid, obimb: 1,2-bis((1H-imidazol-1-yl)methyl)benzene] were obtained and fully characterized by elemental analysis, fourier transform infrared spectroscopy, single crystal and powder X-ray diffractions. In addition, thermal, luminescence, topological and optical properties of the complexes were investigated. According to single crystal X-ray diffraction analysis results, complexes 1, 2 and 3 isomorphous and complex 1 and 2 demonstrated two-dimensional (2D) composed of Co(II) and Zn(II)-containing polymeric chains with distorted tetrahedral geometry. Complex 3 is a 2D coordination polymer containing a Cd(II) ion with a distorted octahedral geometry. According to the results of the topological analysis performed to determine the simplified architectures of the complexes obtained, all structures display sql/Shubnikov topology with the point symbol of (44.62).

Cadmium(II) coordination polymers based on 3,3′-azobis(pyridine) and some aliphatic dicarboxylates: Hydrothermal synthesis, crystal structures, thermal stabilities and photoluminescence

Three new Cd(II) coordination polymers (CPs), namely, [Cd2(µ-phsuc)2(µ-abpy)2(H2O)2]n (1), {[Cd(μ3-glu)(μ-abpy)]⋅3H2O}n (2) and {[Cd(μ-dmglu)(μ-abpy)(H2O)]⋅H2O}n (3), were synthesized by hydrothermally from 3,3′-azobis(pyridine) (abpy) using three different aliphatic dicarboxylic acids [phenyl succinic acid (phsucH2), glutaric acid (gluH2) and 3,3′-dimethyl glutaric acid (dmgluH2)]. The structures of 1–3 were characterized by elemental analysis, infrared spectroscopy (IR), single crystal X-ray and powder X-ray diffraction (PXRD) techniques. X-ray diffraction studies have revealed that 1–3 crystallize in the monoclinic system, P21/n space group (1) and C2/c space group (2, 3). 1 and 2 show 3D structure, whereas 3 exhibits an interesting 2-fold interpenetrating 2D structure. The thermal stabilities of the CPs were studied by thermal analysis (TG/DTA) techniques. In addition, the photoluminescence properties of the CPs have been investigated.

Inserting auxiliary ligand to construct a Cd(II)-based salamo-like coordination polymer as bifunctional chemosensor for detecting picric acid and S2−

A tailored Cd(II) coordination polymer [Cd(HL)2(1,4-pbyb)]n (Cd(II)-CP), has been synthesized successfully by using the host ligand H2L (4‑chloro-4ʹ‑bromo-6‑bromo-6ʹ‑tert‑butyl‑2,2ʹ-[ethylenedioxybis(nitrilomethylidyne)]diphenol) and auxiliary ligand 1,4-di(pyridin-4-yl)benzene (1,4-pbyb) under the room temperature volatilization method. Single crystal X-ray diffraction experiment showed that Cd(II) atoms possess a slightly twisted hexa-coordinated octahedron configuration and Cd(II)-CP forms an infinite 1D zigzag-like chain configuration. The structural diversity of Cd(II)-CP is mainly attributed to the introduction of auxiliary ligand. The Cd(II)-CP is a highly selective and sensitive luminescent bifunctional chemosensor toward nitroaromatic compounds (NACs) and anions, which exhibits turn-off fluorescence effect on picric acid (PA) and turn-on fluorescence effect for sulfide ions (S2−). The sensing mechanisms were also carefully investigated. This study provides new conceptions for the design of CPs for detecting pollutants from surroundings, potentially mitigating health risks to humans and natural ecosystems.

Crystal Growth, Characterization and Photocatalytic Dye Degradation Studies of a Coordination Polymer of Cd(II) with Thiophene-2,5-dicarboxylic Acid and Nicotinamide

A new coordination polymer of Cd(II) of formula {[Cd(TDC)(Nic)(H2O)]·3H2O}n (H2TDC = thiophene-2,5-dicarboxylic acid and Nic = nicotinamide) has been prepared by gel diffusion method. Various analytical techniques such as elemental analysis, single crystal X-ray diffraction, thermogravimetry, FT-IR and UV-visible spectroscopy were used for the characterization of the compound. In the crystal structure, the Cd-thiophene-2,5-dicarboxylate units extend to form 1D chains. Interconnections of 1D chains by the carbonyl oxygen and nitrogen from the pyridine ring of nicotinamide molecules provide a ladder-like structure that possesses 1D channels. Extensive hydrogen bonding results in the formation of a layered structure. Photocatalytic dye degradation property of the coordination polymer was investigated by using methylene blue under sunlight. Photoluminescence and thermal studies were also carried out.

Six novel Zn(II)/Cd(II) coordination polymers based on a rigid tridentate imidazolyl terpyridine ligand fine-tuned by different carboxylates: Syntheses, structural diversities and luminescence properties

Six novel coordination polymers (CPs) based on a rigid tridentate ligand, 4′-(4-(imidazol-1-yl)phenyl)-4,2′:6′,4′'-terpyridine (imphtpy), namely {[Zn2(imphtpy)2(p-bdc)2]·(H2O)}n (1), [Zn(imphtpy)(m-bdc)]n (2), {[Zn(imphtpy)(qda)1.5]·(H2O)}n (3), [Cd2(imphtpy)2(m-bdc)2]n (4), [Cd(imphtpy)(abtc)0.5]n (5) and [Cd(imphtpy)(qda)]n (6), (p-H2bdc = 1,4-benzenedicarboxylic acid, m-H2bdc = 1,3-benzenedicarboxylic acid, H2qda = hydroquinone-o,o'-diacetic acid and H4abtc = 3,3′,5,5′-azobenzenetetracarboxylic acid), have been solvothermally synthesized and characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Complex 1 displays a pseudo four-fold interpenetration of dia network in a [2 + 2] mode. Complex 2 exhibits a 2D → 2D polycatenane of two-fold interpenetrated network with the sql topology. Complex 3 shows a interdigitated 2D layer with the sql topology, which is further extended into a 3D supramolecular framework through π-π interactions and hydrogen bonds. Complex 4 features a two-fold interpenetrated (4,4)-connected 3D + 3D → 3D framework with the bbf topology. Complex 5 reveals a 2D network constructed by binuclear Cd2(CO2)4 secondary building unit (SBU) with the sql topology which is further packed into a 3D supramolecular framework through π-π interactions. Complex 6 is a 3D network constructed by binuclear Cd2(CO2)2O2 SBU with the uninodal 6-c pcu topology. These results indicate that the versatile coordination networks of imphtpy and various polycarboxylate ligands play crucial roles in modulating the structural topologies of coordination networks. In addtion, photoluminescence properties have been explored for complexes 1–6 in the solid state at room temperature, which are derived from metal perturbed intraligand charge transfer (ICT) or ligand-to-ligand charge transfer.

Synthesis, Structures, Luminescence and Catalytic Activity in the Knoevenagel Condensation Reaction of Two Cd(II) Coordination Polymers Based on a Biphenyl-dicarboxylic Acid①

Synthesis, Structures, Luminescence and Catalytic Activity in the Knoevenagel Condensation Reaction of Two Cd(II) Coordination Polymers Based on a Biphenyl-dicarboxylic Acid①

Temperature-controlled Structural Diversity of Two Cd(II) Coordination Polymers Based on the Dicarboxylate Ligand①

Temperature-controlled Structural Diversity of Two Cd(II) Coordination Polymers Based on the Dicarboxylate Ligand①

Catalytic activation of persulfate by 3D Cd(II) coordination polymers based on a flexible cyclotriphosphazene-functionalized ligand

Dye removal in wastewater can be done by catalytic reaction with coordination polymers. Herein, Two 3D Cd(II) coordination polymers, namely, {[Cd3(L)(H2O)4].(H2O)(DMF)}n (GTU-1) and {[Cd3(L)(4,4-bpy))(H2O)2].(H2O)}n (GTU-2), were prepared with a novel hexapod-shaped molecular building block, hexakis(methyl-2-(4-phenoxyphenyl)acetatebenzene) cyclotriphosphazene (H6L), by solvothermal reactions in dimethylformamide with nitric acid as the modulator. Cd(II) coordination polymers were characterized by Fourier transform infrared spectroscopy, thermal analysis, scanning electron microscopy, powder X-ray diffraction analysis and single crystal X-ray diffraction technique. GTU-1 represents a 3D pillared-layered coordination polymer structure containing 2D Cd-carboxylate (Cd(COO)n)-based inorganic building unit (IBU) whereas GTU-2 is a 3D coordination polymer derived from 1D IBU bridged together by deprotonated L6- and judiciously chosen ancillary linker 4,4-bipyridine (4,4-bpy). In both complexes, the flexible multisite cyclotriphosphazene bridging ligand (H6L) is completely deprotonated. GTU-2 exhibited relatively good catalytic activity towards rhodamine B (RhB), Methylen Blue (MB) and Acid Red 17 (AR-17) removal in aqueous solution.

One Cd(II) coordination polymer based on flexible 4,4′-di(4H-1,2,4-triazole-4-yl)methyldiphenyl: Synthesis, structure and luminescent property

Under hydrothermal conditions, one Cd(II) coordination polymer (Cd-CP) has been successfully created using the flexible bis-triazole ligand and dicarboxylate ligand. In Cd-CP, one-dimensional chain structure is created by the interconnection of the adjacent cadmium ions via water bridges. To create a two-dimensional layer structure, the mutually parallel one-dimensional cadmium chains are connected further by dicarboxylate ligands. The final three-dimensional stacking structure is formed by bis-triazole ligands connecting adjacent two-dimensional layers. The theoretical computations and the experimental fluorescence characteristics are in agreement, which shed deep light on the fluorescence properties of Cd-CP. The associated findings demonstrate that the carboxylate and bis-triazole coligands can successfully modify the architectures of coordination polymers, which illustrates the feasibility of constructing functional coordination materials from bis-triazole ligands.