Coordination Polymer Materials Research Articles

Alkoxy-Bridged Dicopper(II) Cores Meet Tetracyanonickelate Linkers: Structural, Magnetic, and Theoretical Investigation of Cu/Ni Coordination Polymers.

Two heterometallic Cu(II)/Ni(II) coordination polymers, [Cu2(Hbdea)2Ni(CN)4]n (1) and [Cu2(dmea)2Ni(CN)4]n·nH2O (2), were successfully self-assembled in water by reacting Cu(II) nitrate with H2bdea (N-butyldiethanolamine) and Hdmea (N,N-dimethylethanolamine) in the presence of sodium hydroxide and [Ni(CN)4]2-. These new coordination polymers were investigated by single-crystal and powder X-ray diffraction and fully characterized by FT-IR spectroscopy, thermogravimetry, elemental analysis, variable-temperature magnetic susceptibility measurements, and theoretical DFT and CASSCF calculations. Despite differences in crystal systems, in both compounds, each dinuclear building block [Cu2(μ-aminopolyalcoholate)2]2+ is bridged by diamagnetic [Ni(CN)4]2- linkers, resulting in 1D (1) or 2D (2) metal-organic architectures. Experimental magnetic studies show that both compounds display strong antiferromagnetic coupling (J = -602.1 cm-1 for 1 and -151 cm-1 for 2) between Cu(II) ions within the dimers mediated by the μ-O-alkoxo bridges. These results are corroborated by the broken symmetry DFT studies, which also provide further insight into the electronic structures of copper dimeric units. By reporting a facile self-assembly synthetic protocol, this study can be a model to widen a still limited family of heterometallic Cu/Ni coordination polymer materials with different functional properties.

Cluster-Spin-Glass Magnetic Behavior and Morphology in the Coordination Polymer Alloys FeyCo1-yBTT.

We report the synthesis of a series of pseudo-1D coordination polymer (CP) materials with the formula FeyCo1-yBTT (BTT = 1,3,5-benzenetrithiolate). These materials were structurally characterized by PXRD Rietveld, EXAFS, and PDF analyses, revealing that the CP superstructure enables a continuous and isomorphous alloy between the two homometallic compounds. Lower Fe loadings exhibit emergent spin glass magnetic behavior, such as memory effects and composition-dependent spin glass response time constants ranging from 6.9 × 10-9 s to 1.8 × 10-6 s. These data are consistent with the formation of spin clusters within the lattice. The magnetic behavior in these materials was modeled via replica exchange Monte Carlo simulation, which provides a good match for the experimentally measured spin glassing and magnetic phase transitions. These findings underscore how the rigid superstructure of CP and MOF scaffolds can enable the systematic tuning of physical properties, such as the spin glass behavior described here.

Ultrafast and Scalable Fabrication of Coordination Polymer Films on Network Substrates via Thermal Current-Induced Dewetting.

Coordination polymers are among the most favored active materials by researchers due to their broad application prospects. However, most of them are usually difficult to directly process into applicable devices because of their unsatisfied processability. One process of great concern for researchers is the in situ preparation of the coordination polymer on the applicable substrate, especially for the favored network substrates with good mechanical properties and 3D porous structure, which could provide obvious convenience and facilitation in the application process. Herein, we present an ultrafast and scalable thermal current-induced dewetting strategy to obtain uniform coordination polymer film in situ on network substrates, which could enable unprecedented convenience to obtain directly usable coordination polymer composites such as practical catalytic electrodes with excellent electrocatalytic performance. The proposed thermal current-induced dewetting method provides a highly adaptable and efficient practical production approach to integrate coordination polymer materials with network substrates and also provides new inspiration for understanding and applying the dewetting process on complex 3D network substrates.

Advanced coordination polymer materials for drug delivery systems

Coordination polymers demonstrated outstanding performance and ability in drug delivery resulting from their porosity and combinatory structure of non-metal and metal. Previous research has made considerable efforts on different aspects of coordination polymers, including synthesises, modifications and pre-clinical studies. Furthermore, among those coordination polymers, metal organic frameworks turn out to be the one that performs best. Therefore, recent researches are more and more inclined to using MOFs as drug delivery systems. This literature review will talk about the current synthesis methodologies of coordination polymers (especially MOFs) and the drug delivery using coordination polymers bulk system, nano-scale coordination polymers system and nano-scale coordination colloids system. Specifically, the mechanisms and the properties of the synthesizing methods and drug delivery systems. This review will conclude the current development of coordination polymers used as drug delivery systems and the newest synthesized approaches. At the same time, the review will also make an outlook towards the future development of the coordination polymers drug delivery systems.

A multifunctional Eu2-cluster coordination polymer as a luminescent probe of imidacloprid and renewable catalyst for the fixation of CO2 with epoxides

A bifunctional coordination polymer material is of great significance for the environmentally friendly applications due to its inherent advantages such as abundant active sites and characteristic metal ions. Here, a 3D Eu2-based framework 1 ({[Eu2(BTB)2(H2O)2]}n, H3BTB = 1,3,5-tris(4-carboxyphenyl)benzene) has been prepared through solvothermal method, presenting excellent chemical stability and thermal stability. Importantly, compound 1 serving as a recyclable luminescence probe (five times) can recognize pesticide imidacloprid with detection limit of 4.9 ppm, featuring good selectivity and anti-interference performance in simulative serum and urine environments. Additionally, in view of abundant Lewis-acid sites, compound 1 can be employed as an efficient catalyst for the conversion reaction of CO2 and epoxides with different substituent groups into high-valued chemical substances (five-cycled carbonate) without solvent. More importantly, this heterogeneous catalyst can be reused without significant change in catalytic activity after five reaction cycles, which are further confirmed by the PXRD, ICP and IR analyses of catalyst 1 after the fifth recycling. This work greatly enriched the applications of multifunctional coordination materials in CO2 cycloaddition catalysis and luminescence sensing.

Dy(OH)3: a paramagnetic magnetocaloric material for hydrogen liquefaction

Dy(OH)3 has impressive magnetocaloric performance optimised around 20 K making it suitable for hydrogen liquefaction using magnetic cooling.

Subtle structural engineering of a coordination polymer host for the fluorescence modulation of host–guest donor–acceptor systems

A novel series of host-guest donor-acceptor (D-A) coordination polymer (CP) materials have been fabricated by subtle structural engineering, which presented multifarious emission properties and illustrated the great potential in achieving fluorescence modulation.

Rapidly Photocurable Solid-State Poly(ionic liquid) Ionogels For Thermally Robust and Flexible Electrochromic Devices.

Formation of ionogels through in situ polymerization can effectively improve electrolyte processability; however, the curing process has been slow and oxygen-sensitive. Considering the low oxygen solubility of poly(ionic liquid)s (PILs), in situ polymerized ionogels are designed to realize excellent electrolytes. Herein, two in situ polymerized ionogels (PIL A & PIL B) are formulated, and they can be rapidly photocured within a minute. The ionogels are highly transparent, stretchable, and exhibit excellent physicochemical stability, including thermal, electrochemical, and air stability, allowing them to perform in various conditions. Benefitting from these properties, two high-performance electrochromic devices (ECDs) are assembled, with iron-centered coordination polymer (FeCP) and tungsten oxide (P-WO3 ) electrochromic materials, achieving high color contrast (45.2% and 56.4%), fast response time (1.5/1.9 and 1.7/6.4 s), and excellent cycling endurance (>90% retention over 3000 cycles). Attributed to the thermal robustness of the ionogels, the ECDs can also be operated over a wide temperature range (-20 to 100 °C). With the use of deformable substrates (e.g., ultrathin ITO glass), curved electrochromic eye protector and flexible electrochromic displays are realized, highlighting their potential use in futuristic wearables.

Biological activity of Cu(II)-coordination polymer in functional dyspepsia and the design of novel pharmaceutical structure using supervised learning technic

Based on 4′-[4,2′;6′,4″] terpyridin-4′-yl-biphenyl-4-carboxylic acid (Htpbpc) and 1,4-benzenedicarboxylic acid (H2bdc) mixed linkers, a new Cu(II) coordination polymer material, [Cu(tpbpc)(bdc)0.5·H2O]·4H2O (1), has been successfully prepared under the solvothermal reaction conditions. After the treatment of the new compound, the application values on functional dyspepsia disease were evaluated. Firstly, the Ghreli, Leptin and PYY content in the plasma of the animal was measured with ELISA assay. Then, the relative expression of the Ghreli, Leptin and PYY in the gastric antrum was determined with real time RT-PCR assay. The results from supervised machine learning found that the predicted molecules have better biological activities than the experimentally verified Cu complex, each of the selected new molecules has more binding interactions within the binding pocket of Ghrelin, which demonstrates that the supervised machine learning technic is an effective approach for the design of novel pharmaceutical molecules.

A Double‐Helix Metal‐Chain Metal‐Organic Framework as a High‐Output Triboelectric Nanogenerator Material for Self‐Powered Anticorrosion

AbstractThe development of novel metal organic framework (MOF) friction power generation materials with high stability is important. This paper reports the first example of a double‐helix metal chain organic framework with a network structure (ZUT‐8). ZUT‐8 shows high chemical stability, functional adjustability, and excellent output performance of friction power generation, which is superior to traditional coordination polymer materials. The cathodic protection system with ZUT‐8 can prevent metal corrosion significantly. The output performance can be improved effectively by enhancing the conjugate effect of the linker. The theoretical calculation results showed that an increase in the degree of conjugation could significantly reduce the band gap, thereby affecting the friction power output signal. This study opens the door to constructing MOF materials with a double‐helix metal chain and will promote their potential applications in self‐powered electrochemical cathodic protection.

A Double-Helix Metal-Chain Metal-Organic Framework as a High-Output Triboelectric Nanogenerator Material for Self-Powered Anticorrosion.

The development of novel metal organic framework (MOF) friction power generation materials with high stability is important. This paper reports the first example of a double-helix metal chain organic framework with a network structure (ZUT-8). ZUT-8 shows high chemical stability, functional adjustability, and excellent output performance of friction power generation, which is superior to traditional coordination polymer materials. The cathodic protection system with ZUT-8 can prevent metal corrosion significantly. The output performance can be improved effectively by enhancing the conjugate effect of the linker. The theoretical calculation results showed that an increase in the degree of conjugation could significantly reduce the band gap, thereby affecting the friction power output signal. This study opens the door to constructing MOF materials with a double-helix metal chain and will promote their potential applications in self-powered electrochemical cathodic protection.

Two-dimensional dysprosium(III) coordination polymer: Structure, single-molecule magnetic behavior, proton conduction, and luminescence.

A new dysprosium (III) coordination polymer [Dy(Hm-dobdc) (H2O)2]·H2O (Dy-CP), was hydrothermal synthesized based on 4,6-dioxido-1,3-benzenedicarboxylate (H4m-dobdc) ligand containing carboxyl and phenolic hydroxyl groups. The Dy(III) center adopts an octa-coordinated [DyO8] geometry, which can be described as a twisted square antiprism (D 4d symmetry). Neighboring Dy(III) ions are interconnected by deprotonated Hm-dobdc3− ligand to form the two-dimensional infinite layers, which are further linked to generate three-dimensional structure through abundant hydrogen bonds mediated primarily by coordinated and lattice H2O molecules. Magnetic studies demonstrates that Dy-CP shows the field-induced slow relaxation of magnetization and the energy barrier U eff/k B and relaxation time τ 0 are 35.3 K and 1.31 × 10–6 s, respectively. Following the vehicular mechanism, Dy-CP displays proton conductivity with σ equal to 7.77 × 10–8 S cm−1 at 353 K and 30%RH. Moreover, luminescence spectra reveal that H4m-dobdc can sensitize characteristic luminescence of Dy(III) ion. Herein, good magnetism, proton conduction, and luminescence are simultaneously achieved, and thus, Dy-CP is a potential multifunctional coordination polymer material.

A X-ray responsive scintillating coordination polymer constructed by lead(II) and anthracene derivative

The strong X-ray attenuation and beneficial optoelectronic properties of lead(II)-based coordination polymers (CPs) materials have aroused great interest in the field of radiation detection. In this work, a X-ray responsive scintillating 1D Pb(II)-CP [Pb(adba)(DMF)]n (named as Pb-adba, H2adba = 4,4′-(9,10-anthracenediyl)dibenzoic acid, DMF = N, N-dimethylformamide) with favourable irradiation stability was synthesized by the self-assembly approach, which exhibits competitive sensitivity and detection limit toward X-ray than classical scintillators PbWO4 (PWO), anthracene and some reported SMOFs.

The syntheses and efficient electromagnetic wave absorption properties of two Cu based coordination polymers

Two Cu based coordination polymers (CPs) materials, namely, and [Cu(MHP)4]n·H2O] (1) (MHP = methyl hydrogen phthalate), and [Cu (TFBDC)]n·DMF] (2) (TFBDC = 2,3,5,6-tetrafluoroterephthalic acid) are synthetized by traditional slow volatilization method. The structures are elucidated clearly, and both CPs are characterized by elemental analyses, powder X-ray diffraction (PXRD), as well. The single crystal X-ray diffraction studies indicate that CP 1 and CP 2 are three-dimensional frameworks. The EMWA investigation manifests that both two CPs materials are effective electromagnetic wave absorbent. Furthermore, the dye adsorption capacities of CP 2 are evaluated by several organic dyes. The result shows that CP 2 has 99.9% remove efficiency to Congo red. Therefore, CP 2 is an ideal Congo red adsorbent in aqueous solution.

Barium-based coordination polymer: A bi-functional fluorescent sensor for Fe3+ and nitroaromatic molecular detection

It is important to develop a simple and multi-response fluorescence sensor for practical applications. Coordination polymer materials are widely used in fluorescence sensor design due to their excellent photoluminescence properties. Herein, a new 2D coordination polymer [Ba(Nyaia)(H2O)]n 1 (H2Nyaia = 5-[(naphthalene-1-methylene)amino]-isophthalic acid) with good thermal stability was prepared through H2Nyaia and barium(II) nitrate under the solvothermal method. Compound 1 as a bi-functional fluorescent sensor has highly sensitive fluorescence quenching for detecting Fe3+ with the quenching constant (Ksv) value of 6.57 × 105 M−1 and 4-nitrophenol (4-NP) with the Ksv value of 4.44 × 105 M−1.

(4,5,8)-Connected Cationic Coordination Polymer Material as Explosive Chemosensor Based on the in Situ Generated AIE Tetrazolyl-Tetraphenylethylene Derivative.

A multidentate tetrazole molecule based on a TPE core, tetrakis[4-(1H-tetrazol-5-yl)phenyl]ethylene (H4ttpe) with combined advantages of two functional groups, was synthesized by cycloaddition reaction of the corresponding organic benzonitrile derivative and azide salt. Coordination self-assembly of the in situ formed aggregation-induced emission polytetrazole luminogen with cadmium(II) ion produces an unprecedented tetrazolyl-TPE-based microporous cationic metal-organic framework (MOF) with an unusual (4,5,8T14)-connected net of {[Cd4(H4ttpe)2Cl5]·(N3)3}, in which the H4ttpe serves as the first undeprotonated tetrazole ligand of octa-coordinating bridging mode. We investigate, for the first time, the utilization of the luminescent MOF containing a TPE core decorated with tetrazolyl terminals for explosive detection based on the change in fluorescence intensity, which shows high selectivity and efficiency in fluorescence quenching toward TNP detection in water solution.

Preparation and Application of Keggin Polyoxometalate‐based 3D Coordination polymer Materials as Supercapacitors and Amperometric Sensors

AbstractThe development of POM‐based coordination polymers (CPs) provides a promising chance to approach excellent bifunctional electrode materials. Herein, three new polyoxometalates (POMs)‐based three‐dimensional (3D) inorganic‐organic hybrid compounds, [HPMVI9MV3O40]CuI5[4‐atrz]6⋅XH2O [M=Mo(1) or W(2), X=1(1)], [H2SiMoVI9MoV3O40]CuI5[4‐atrz]6⋅H2O (3) have been synthesized via hydrothermal reaction and explored as pseudocapacitive and sensors electrode materials. These compounds possess a novel three‐dimensional sandwich structure formed from POMs and ring CuI‐4‐atrz complexes by using Cu1 as nodes. As capacitor electrode materials, compounds 1 and 3 with Mo‐containing POMs show much higher specific capacitance than 2, which is because that POMs with Mo as metal atoms have much higher oxidation capacity than those with W. When these compounds are used as sensors to detect NO2− and Cr2O72−, compound 3 shows the highest sensitivity, lowest detection limit and most excellent anti‐interference ability. These results indicate that combining POMs and CuI‐4‐atrz complexes to form POM‐based coordination polymers with unique microstructures greatly improve the electrochemical performance and stability of traditional POMs as electrode materials, which are attributed to excellent redox properties of POMs, and unique three‐dimensional structure formed due to introduction of Cu‐4‐atrz complex. This work provides a promising direction for exploring novel bifunctional electrode materials.

Structure and Facile Synthesis of Proton-Conducting [Fe(CN)

Proton-conducting materials are a key component of proton exchange membrane fuel cells (PEMFCs) and the advantage of clear structural information in crystal materials offers a pathway for the investigation of the proton-conducting mechanism and pathway. In this work, a new Cd2+ coordination polymer material (compound 1) with the formula {[Cd3(bipy)3(H2O)4][Fe(CN)6]2·2H2O·2(bipy)}n was successfully synthesized by a solution diffusion method and its proton conduction ability was further determined. Crystal structure analysis confirms the coordination of [Fe(CN)6]3–, 4,4′-bipyridine, and H2O molecules to Cd2+ in the three dimensional structure of compound 1. Also, we confirmed that compound 1 of 500–800 nm particle size could be synthesized on a large scale by a facile stirring method. Proton-conductivity analyses revealed that compound 1 shows a water-mediated proton conduction behaviour because the conductivity increased apparently with the increase of relative humidity. Further investigation shows that the highest proton-conductivity of 8.36 × 10−4 S cm−1 was observed at 60°C and 95 % relative humidity, and the mechanism analysis suggests a Vehicle mechanism exists in the proton conduction process of compound 1.

Copper triazine polycarboxylic acid crystalline framework materials: Synthesis, structure and multifunctional properties with the luminescent and catalytic reduction of 4-NP

Metal-organic frameworks are a class of promising materials that are widely used in various fields such as detection, catalysis, and adsorption. A new protonated coordination polymer [Cu2(H2TTHA)(H2O)6] (1) containing two uncoordinated carboxylate acid groups was synthesized under the condition of hydrothermal, and a series of characterizations including elemental analysis, infrared spectroscopy, PXRD, thermogravimetric analysis, and ultraviolet–visible spectroscopy were performed. It has a 3D supramolecular network structure. In order to further study the reproducible synthesis conditions, we unexpectedly got a partly protonated coordination polymer material [Cu3(H3TTHA)(μ3-O)(μ3-OH)(μ2-H2O)2(H2O)]·2H2O (2), which was different from the structure of 1 and contained three uncoordinated carboxylate acid groups in the framework structure. It was found that coordination polymer 1 has good catalytic activity for the catalytic reduction of 4-NP under mild reaction conditions. In the meantime, it can be used as a sensor to detect a small amount of Fe3+ (1 mM), and the detection limit for Fe3+ is 21 μM. The results show that 1 possesses a good application prospect in terms of fluorescence sensing and catalysis.

Multi‐Mode Color‐Tunable Long Persistent Luminescence in Single‐Component Coordination Polymers

AbstractMaterials with tunable long persistent luminescence (LPL) properties have wide applications in security signs, anti‐counterfeiting, data encrypting, and other fields. However, the majority of reported tunable LPL materials are pure organic molecules or polymers. Herein, a series of metal‐organic coordination polymers displaying color‐tunable LPL were synthesized by the self‐assembly of HTzPTpy ligand with different cadmium halides (X=Cl, Br, and I). In the solid state, their LPL emission colors can be tuned by the time‐evolution, as well as excitation and temperature variation, realizing multi‐mode dynamic color tuning from green to yellow or green to red, and are the first such examples in single‐component coordination polymer materials. Single‐crystal X‐ray diffraction analysis and theoretical calculations reveal that the modification of LPL is due to the balanced action from single molecule and aggregate triplet excited states caused by an external heavy‐atom effect. The results show that the rational introduction of different halide anions into coordination polymers can realize multi‐color LPL.