Search Results (109)

Development of new polymers that cannot be achieved by using conventional catalysts has been the central research objective, and copolymerization is an effective strategy to modify the materials’ (thermal, physical, mechanical and electronic) properties. Modified half-titanocenes, Cp’TiX₂(Y) (Cp’ = cyclopentadienyl, X = Cl, Me, etc, Y = anionic donor such as phenoxide, ketimide, amidinate, etc.), are known to be effective catalysts. This review introduces several selected efforts for efficient synthesis of ethylene copolymers containing cyclic olefins, biobased conjugated dienes, and disubstituted α-olefins, including the effect of cocatalysts. Moreover, here we introduce an analysis using XAS (X-ray absorption spectroscopy), which has been recognized as a powerful method providing direct information on the catalytically active species, such as coordination numbers and the distances of the coordinated atoms as well as oxidation state and the geometry of the metal centre in catalyst solution. Full article

The investigation primarily focuses on synthesizing Polyvinyl Chloride (PVC)-coordination polymer (CP) polymeric membranes that employ L-Cu-NO₃ (¹_∞[Cu₃L₂(NO₃)]NO₃·2MeOH·2H₂O based on the Schiff base H₂L, where H₂L stands for N,N’-bis[(2-hydroxybenzilideneamino)-propyl]-piperazine)) as a coordination polymer. The membrane’s capacity to hold moisture is greatly improved by the addition of CPs. The water contact angle dropped from 73.4° for the PVC to about 71° for the composite membrane, indicating that the CP–PVC polymer interactions improved the hydrophilicity. Impedance spectroscopy (EIS) was used to determine the membranes response to the tested concentrations of phenol solution at pH 9.11 in the concentration range of 10⁻¹⁰ to 10⁻² mol·L⁻¹. A PVC membrane with a 0.6 wt% L-Cu-NO₃ deposit on a Cu electrode yields the best response. Between 10⁻⁸ and 10⁻⁵ mol·L⁻¹ phenol, a linear dependence was found. The detection limit was 4.64 × 10⁻⁸ mol·L⁻¹. Full article

By the reaction of AgNO₃, 2-methyl-2-propanethiol (HStBu), with various-sized halogen ions as templates, three multi-nuclear silver-thiolate cluster-based chain-like coordination polymers, [Ag₆(μ-SBu)₆]_n (USC-CP-2), [Ag₆(μ-StBu)₅Br]_n (USC-CP-4) and [Ag₁₄(μ-StBu)₁₂I₂]_n (USC-CP-3) constructed by different Ag(I)-nanocages, have been synthesized and characterized by X-ray diffraction analyses. With F⁻, Cl⁻ or without template, USC-CP-2 exhibits a one-dimensional structure composed of detached Ag₆-cages, absent of fluoride or chloridion. While with Br⁻ and I⁻, USC-CP-4 and USC-CP-3, two distinct halogen-templating multi-sliver cages-based chain-like polymeric structures have been observed, which are a mono-Br⁻ encapsulated Ag₈-cage, or a dual-I⁻ embedded Ag₁₆-cage, respectively. In these three compounds, the multi-Ag(I) cages were self-assembled by Ag-S bonds through bridged μ₂-StBu ligands, and stabilized argentophilic interactions between neighboring silver atoms. This study demonstrates that the halide anions of varying sizes play a critical role in inducing the nucleation and structural evolution of the silver-thiolate clusters. Full article

Coordination polymers (CPs) are garnering attention in the field of medicine day by day. The goal is to develop a CP with biosafe and environment-friendly characteristics. Herein, we report two such novel 3D coordination polymers of zinc-inosine-5′-monophosphate (Zn-IMP) and bpe/azpy (as linkers) which were engineered as metal–organic frameworks that can be used as drug carriers for hydroxyurea (HU). We employed SCXRD, PXRD, solid-state CD, FTIR and TGA for crystal structure characterizations; the results achieved 3D coordination polymers which contain a P2₁ space group with chiral distorted tetrahedral geometry. Solution phase studies like UV–vis and CD were carried out to understand mechanistic pathways for interaction and chirality, respectively. We have also performed computational studies to evaluate the drug delivery capacity of both 3D CPs. Molecular docking and multi-pH molecular dynamics (MD) quantify that HU binds more strongly with CP−1 (ΔG =−10.87 ± 0.12) as compared to CP−2 (ΔG = −7.59 ± 0.26 kcal·mol⁻¹), at normal and basic pH. MD simulation analysis indicated that a more compact and rigid cavity is observed by CP−1 as compared to CP−2 at physiological pH. Across acidic pH, for CP−1 the ligand RMSD increases markedly and U becomes slightly less negative, which indicated partial loss of contacts, thus releasing drugs in a tumor-like environment more easily. These result showed that CP−1 offers stronger binding, higher structural stability and a more pronounced pH-responsive release profile than CP−2, making CP-1 more promising candidate for targeted HU drug delivery, while CP−2 may serve as a weaker-binding, faster-release complement. Full article

This paper demonstrates the successful synthesis of novel hybrid heterogeneous catalysts for the sustainable conversion of CO₂ into cyclic organic carbonates (COCs). The nanocat-alysts have been fabricated by encapsulating pre-formed ultra-small gold nanostructures into a nascent zinc-coordination polymer (ZnCP) framework formed from two organic building blocks, 2,4-naphthalenedicarboxylic acid (1,4-NDC) and 5-amino-1H-tetrazole (5-Atz), which serves as a nitrogen-rich ligand. Applying the fabricated catalysts in the synthesis of COCs yields high yields (up to 97%) and high selectivity (up to 100%), with exceptionally high turnover frequencies (TOFs) (up to 408 h⁻¹). The catalytic process can be carried out under mild conditions (80 °C, 1.5 MPa CO₂) and without the use of solvents. Nitrogen-rich ligand molecules in the structure of ZnCPs enhance catalytic performance thanks to additional nucleophilic centres, which are effective in the epoxides’ ring-opening process. The hybrid catalysts with encapsulated gold nanostructures, which modify the liquid–gas interface between epoxide and CO₂, give significantly higher yields and TOFs for less active epoxides. The designed hybrid nanocatalysts exhibit superior stability under the studied reaction conditions and can be reused without loss of activity. The developed coordination polymers are constructed from green components, and green chemistry principles are applied to prepare these catalytic materials. Full article

Magnesium phosphate cement (MPC) has gained attention in specialized construction applications due to its rapid setting and high early strength, though its inherent brittleness limits structural performance. This study developed an innovative toughening strategy through synergistic reinforcement using hybrid fibers and carbon fiber-reinforced polymer (CFRP) fabric capable of multi-scale crack control. The experimental program systematically evaluated the hybrid fiber system, dosage, and CFRP positioning effects through mechanical testing of 7-day cured specimens. The results indicated that 3.5% fiber dosage optimized flexural–compressive balance (45% flexural gain with <20% compressive reduction), while CFRP integration at 19 mm displacement enhanced flexural capacity via multi-scale reinforcement. Fracture analysis revealed that the combined system increases post-cracking strength by 60% through coordinated crack bridging at micro (fiber) and macro (CFRP) scales. These findings elucidated the mechanisms by which fiber–CFRP interaction mitigates MPC’s brittleness through hierarchical crack control while maintaining its rapid hardening advantages. The study established quantitative design guidelines, showing the fiber composition of CF/WSF/CPS15 = 1/1/1 with 19 mm CFRP placement achieves optimal toughness–flexural balance (f_f/f_c > 0.38). The developed composite system reduced brittleness through effective crack suppression across scales, confirming its capability to transform fracture behavior from brittle to quasi-ductile. This work advances MPC’s engineering applicability by resolving its mechanical limitations through rationally designed composite systems, with particular relevance to rapid repair scenarios requiring both early strength and damage tolerance, expanding its potential in specialized construction where conventional cement proves inadequate. Full article

The design of suitable chemosensors for environmental pollutants and toxins detection at trace levels remains a critical area of research. Among various chemosensors, Zn(II) coordination polymers have garnered special interest as fluorescent probes for environmental applications. In this article, we report the synthesis of a nitrogen-rich luminescent Zn(II) coordination polymer, TDPAT-Zn-CP, designed for differential fluorescent sensing of antibiotics in an aqueous medium. TDPAT-Zn-CP was synthesized using a star-shaped 2,4,6-tris(di-2-pyridylamino)-1,3,5-triazine (TDPAT) fluorophore, a promising blue-emitting compound. The morphological and structural properties of TDPAT-Zn-CP were thoroughly analyzed using conventional spectroscopic and analytical techniques. The fluorescence titration studies in aqueous medium demonstrated that TDPAT-Zn-CP exhibits remarkable selectivity, sensitivity, and differential fluorescence sensing responses towards various antibiotics. Among the antibiotics tested, TDPAT-Zn-CP displayed a significant fluorescence quenching and high selectivity for sulfamethazine (SMZ), with a Stern–Volmer quenching constant of K_SV = 1.68 × 10⁴ M⁻¹ and an impressive sensitivity of 4.95 ppb. These results highlight the potential of TDPAT-Zn-CP as a practically useful, highly effective polymeric sensor for the differential fluorescence-based detection of antibiotics in water, offering a promising approach for environmental monitoring and contamination control. Full article

The synthesis and characterization of two novel redox-active MOFs/CPs based on 3d transition metal ions and 3,6-ditriazolyl-2,5-dihydroxybenzoquinone (trz₂An) are reported herein. By combining trz₂An with Ni^II and Mn^II ions via the hydrothermal method, two phases, formulated as [Ni₂(trz₂An)₂]·2.5H₂O (1) and [Mn(trz₂An)(H₂O)]·1.5H₂O (2), are obtained. Both compounds crystallize as neutral polymeric 3D frameworks, where the metal ions are coordinated through the oxygen atoms of the anilate linkers forming either straight (1) or zig-zag (2) 1D chains. In particular, (1) is a MOF, where these chains are connected through the nitrogen atom at the 4 position of the triazolyl group, which completes the coordination sphere of each metal ion, affording a 3D structure containing a void volume of 28.7% and voids that can be useful for the sorption of small molecules. Interestingly, (1) and (2) show a redox behavior due to the presence of the anilate linker, being reduced electrochemically in the −0.7 to −0.9 V range due to the benzoquinone–semiquinone one-electron reduction and magnetic behavior dominated by antiferromagnetic interactions in the anilate 1D chains. Full article

Due to its excellent visible light absorption characteristics, the photocurrent, photodegradation, and proton conductivity of the stable dipyridyl and thiophene-functionalized supramolecular compound [Cu₂(TAA)₄(4,4′-bpy)]_n (Cu^II₂ for short, HTAA = 2-thiopheneacetic acid, 4,4′-bpy = 4,4′-bipyridine) have been studied in detail. The current density of photocurrent of Cu^II₂ is 1.87 μA·cm⁻², and Cu^II₂ degrades methylene blue (MB) with a degradation efficiency of 68.0% under xenon lamp. In addition, Cu^II₂ shows remarkable proton conductivity of 1.79 × 10⁻³ S·cm⁻¹ (at 75 °C and 98% relative humidity), superior to most copper(II)-based coordination polymers (CPs), and is expected to become a potential proton conductor in the future. Full article

The reaction of copper nitrate, phthalic acid (1,2-H₂BDC), and bipyridine in ammonia/ethanol media affords two multi-copper (II) cluster-based coordination polymers, namely {[Cu₄(bpy)₄(OH)₂(BDC)₂]·2OH·13H₂O}_n (USC-CP-6) and {[Cu₂(BDC)₂(bpy)₂(H₂O)]·3H₂O}_n (USC-CP-7), under ambient conditions, with CP-6 forming at the bottom and CP-7 at the upper edge of the same beaker. The single-crystal structures reveal that it is a rare case of gradient-induced formation of different multi-copper(II) cluster-based CPs within a single-solution chemical reaction. CP-6 crystallizes in the monoclinic system, sp. gr. P2₁/c, and is composed of chair-like tetranuclear [Cu₄(μ₃-OH)₂(bpy)₄(BDC)₂]²⁺ clusters as secondary building units, bridged by BDC²⁻ ligands to form a two-dimensional layer framework, while CP-7 crystallizes in the monoclinic system, sp. gr. P2₁/n, with binuclear [Cu₂(1,2-BDC)₂(bpy)₂(H₂O)] clusters linked by bridging BDC²⁻ ligands to form a one-dimensional looped double chain. Through intermolecular π–π stacking and hydrogen bonds between the coordination water, lattice water, and free oxygen atoms from carboxylate, both compounds yield a 3D supramolecular structure. Full article

The present study reports the application of three copper(II) coordination polymers, namely ¹_∞[Cu₃L₂(N₃)] CH₃COO (CP1), ¹_∞[Cu₃L₂(NO₃)]NO₃·2CH₃OH·2H₂O (CP2), and ¹_∞[Cu₃L₂(H₂O)](ClO₄)₂ (CP3), where H₂L stands for N,N′-bis[(2-hydroxybenzilideneamino)propyl]-piperazine) as catalysts for photocatalytic degradation of Acid Orange 7 and Methyl Orange dyes from single and binary aqueous solutions. The influence of the photocatalyst nature, hydrogen peroxide presence, reaction time, dye concentration, and catalyst dose on the photodegradation efficiency was studied. Under visible light irradiation, complex CP1 demonstrated the highest photodegradation efficiency of 92.40% and 80.50% towards Acid Orange 7 and Methyl Orange, respectively. The kinetic studies indicated that the photodegradation process followed a pseudo-first-order kinetics. The highest rate of the degradation process was obtained when CP1 is used, and the necessary time for the degradation of the dyes increases with increasing concentration of the dye solutions. The degradation efficiency of more than 75% after five recycling/reuse cycles of CP1 and the yields higher than 72% obtained for the degradation of dyes from the binary system demonstrate the photocatalytic capacity of CP1. A photocatalytic oxidation mechanism was proposed and the stability of the CP1 complex before and after the photodegradation process of dyes, both from simple and binary solutions, was investigated and confirmed. Full article

This review provides an overview of the synthesis, characterization and application of coordination polymers based on N,O-donor Schiff base ligands. The coordination polymers (CPs) represent a novel class of inorganic–organic hybrid materials with tunable compositions and fascinating structures. They are composed of metal ions and organic ligands. Therefore, the nature of the metal ion and type of organic ligand is the most significant factor in constructing targeted coordination polymers with the desired properties. Due to the versatile coordination modes, N,O-donor Schiff base ligands are also used to construct various CPs. Full article

Two new Cu(II) (CP1) and Co(II) (CP2) coordination polymers (CPs) with the triazole ligand 5-methyl-1-(pyridin-4-yl-methyl)-1H-1,2,3-triazole-4-carboxylate (L1) have been synthesized and structurally characterized by SCXRD (Single Crystal X-Ray Difraccion), PXRD (Power X-Ray Difracction), FT-IR (Fourier Transform Infrared), TG (Theermo Gravimetric), and electrochemical techniques. Both CPs were obtained at the water/n-butanol interface by reacting nitrate salts of each metal with the NaL1 ligand. SCXRD analysis revealed that CP1 (Coordination Polymer 1) and CP2 (Coordination Polymer 2) crystallize in the monoclinic space groups C2/c (No. 15) and P2₁/n (No. 14), respectively, forming 1D zigzag chain structures, which further lead to a 2D supramolecular network through O-H⋯O and C-H⋯O hydrogen bond interactions, respectively. In CP1, the supramolecular structure is assembled by hydrogen bonds involving water molecules. In contrast, CP2 forms its supramolecular network mainly through hydrogen bonds between adjacent triazole ligand molecules. Hirshfeld surface analysis revealed that the most significant contributions to the crystal packing come from H⋯O/O⋯H, H⋯H, H⋯N/N⋯H, and H⋯C/C⋯H interactions. In addition, FT-IR provided information on the functional groups involved in the coordination, while the decomposition patterns of both CPs were evaluated by TGA. Electrochemical studies conducted in a saline environment showed that CP1 exhibits superior hydrogen evolution reaction (HER) kinetics compared to CP2, as evidenced by a higher exchange current density and a lower Tafel slope. Density functional theory calculations and experimental bandgap measurements provided a deeper understanding of the electronic properties influencing the electrochemical behavior. The results highlight the potential of CP1 as an efficient catalyst for HER under saline conditions. Full article

Ratiometric lanthanide coordination polymers (Ln-CPs) are advanced materials that combine the unique optical properties of lanthanide ions (e.g., Eu³⁺, Tb³⁺, Ce³⁺) with the structural flexibility and tunability of coordination polymers. These materials are widely used in biological and chemical sensing, environmental monitoring, and medical diagnostics due to their narrow-band emission, long fluorescence lifetimes, and excellent resistance to photobleaching. This review focuses on the composition, sensing mechanisms, and applications of ratiometric Ln-CPs. The ratiometric fluorescence mechanism relies on two distinct emission bands, which provides a self-calibrating, reliable, and precise method for detection. The relative intensity ratio between these bands varies with the concentration of the target analyte, enabling real-time monitoring and minimizing environmental interference. This ratiometric approach is particularly suitable for detecting trace analytes and for use in complex environments where factors like background noise, temperature fluctuations, and light intensity variations may affect the results. Finally, we outline future research directions for improving the design and synthesis of ratiometric Ln-CPs, such as incorporating long-lifetime reference luminescent molecules, exploring near-infrared emission systems, and developing up-conversion or two-photon luminescent materials. Progress in these areas could significantly broaden the scope of ratiometric Ln-CP applications, especially in biosensing, environmental monitoring, and other advanced fields. Full article

This review examines the recent advancements and unique properties of polymer–inorganic hybrid materials formed through coordination bonding (Class II hybrids), which enable enhanced functionality and stability across various applications. Here, we categorize these materials based on properties gained through complexation, focusing on electrical conductivity, thermal stability, photophysical characteristics, catalytic activity, and nanoscale self-assembly. Two major synthetic approaches to making these hybrids include homogeneous and heterogeneous methods, each with distinct tradeoffs: Homogeneous synthesis is straightforward but requires favorable mixing between inorganic and polymer species, which are predominantly water-soluble complexes. In contrast, heterogeneous methods are post-processing techniques that provide high area selectivity for inorganic precursors, allowing precise integration within polymer matrices. Finally, we highlight the role of hybrid linkers, namely metallosupramolecular polymers, in creating structural diversity. These can be organized into three main groups: metal–organic frameworks (MOFs), coordination polymers (CPs), and supramolecular coordination complexes (SCCs). Each of these groups introduces unique structural and functional properties that expand the potential applications of hybrid materials. Full article