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In this work, a coordination polymer based on cobalt terephthalate was obtained and characterized by elemental analysis, infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy. The coordination polymer was tested as a sorbent for the solid-phase extraction of cephalosporin antibiotics, including ceftriaxone, cefotaxime, and cefazolin, from aqueous solutions. The coordination polymer had a high adsorption capacity (520.0 mg/g). Antibiotics adsorption followed pseudo-second order kinetic model and the Freundlich isotherm model. The calculated thermodynamic parameters indicate a spontaneous process. The resulting coordination polymer has good stability and reusability. The possibility of separating the studied cephalosporins on a chromatographic column filled with a coordination polymer was shown. This work opens great prospects for the development and application of a coordination polymer based on cobalt terephthalate for the removal of cephalosporins from ambient water.

At present, conjugated thermolysis of metal-containing monomers is widely used as single-source precursors to obtain new metal- and metal oxide-containing nanocomposites. In this study, a detailed analysis of the main stages of conjugated thermolysis of silver itaconate was carried out. The obtained nanocomposites containing silver nanoparticles are evenly distributed in a stabilizing carbon matrix. The structural characteristics and properties of the resulting nanomaterials were studied using X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). We have developed a method of test analysis of chlorides using paper modified with the obtained silver-containing nanocomposites. The analysis technique is based on the in situ conversion of chlorides to molecular chlorine, its dynamic release, and colorimetric detection using NP-modified paper test strips. A simple installation device is described that allows this combination to be realized. The proposed approach seems promising for nanoparticle-based determinations of other analytes that can be converted into volatile derivatives.

Effective removal of organic dyes from aqueous solution is an important task for targeted wastewater treatment. In this work, a mixed-ligand Zr(IV) metal organic framework based on terephthalic acid and 1,10-phenanthroline was used for the solid-phase extraction of dyes. The maximum adsorption capacity of the sorbent for Congo red and methylene blue dyes reached 40 mg/g. The adsorption behavior was studied, including the effect of time, temperature, adsorbent dosage, pH and coexisting ions. The reliability of the sorbent for removing artificial dyes from food samples and in artificial seawater was tested. The possibility of using the sorbent as a filler for column chromatography for dye separation is shown.

MOF based on cobalt terephthalate and 1,10-phenanthroline was synthesized according to a modified procedure by the interaction of cobalt nitrate, terephthalic acid, and 1,10-phenanthroline in the presence of alkali. MOF has been used to extract the organic Congo red and methylene blue dyes from their aqueous solutions. The degree of removal depends on temperature and reaches values close to 100% within 60 min at 291 and 308 K. The limiting adsorption is 40 mg/g, and the Langmuir model is in good agreement with the experimental results. The antioxidant activity of MOF was evaluated on a model solution of adrenalin hydrochloride in an alkaline medium with a maximum inhibition of the oxidation of the model compound of 87.05%. The antibacterial activity of MOF against Escherichia coli (E. coli) was assessed as satisfactory, which is explained by the release of metal cations and organic ligand, and the long period of action is due to their synergistic action.

The reaction of cobalt(II) acetate with 2-iodoterephthalic acid and 1,10-phenanthroline (phen) in N,N-dimethylformamide (DMF) leads to formation of two products, hexakis(N,N-dimethyl-formamide-κO)c...

Metal-containing monomers based on maleates of copper and zinc, cinnamate of copper and acrylate of zinc with 4-phenyl-2,2′:6′,2′′-terpyridine ligand were prepared for the first time and characterized using a number of analytical techniques including infrared spectroscopy, elemental analysis and thermal gravimetric analysis. According to the results of the thermal analysis, the coordination mixed-ligand complexes based on zinc salts are more stable than copper one both in the case of monocarboxylic acids and dicarboxylic acids. The first stage of polymerization according to results of mass spectra of gaseous products is initiated in accordance with the Borodin–Hunsdiecker mechanism: the initial decarboxylation leads to the formation of carboxy biradicals, which, in turn, cause the polymerization and the formation of polymers. In this paper we also describe facile two-step Kröhnke-type synthesis of 4′-phenyl-2,2′:6′,2′′-terpyridine from 2-acetylpyridine and its NMR spectrum.

Copper trimesinate complexes Cu3(BTC)2L3 and Cu3(BTC)2L with polypyridine ligands, such as 2,2′-bipyridyl, 1,10-phenanthroline, and 4′-phenylterpyridine, were synthesized. Properties and adsorption capacity of compounds obtained in relation to aqueous solutions of pollutants were investigated.

New complex (1) based on nickel(II) maleate and 4′-phenyl-2,2′:6′,2″-terpyridine (L) was synthesized. The complex 1 is a 1D coordination polymer formed from a L-Ni(II) node bridged by maleate ligands and crystallizes in monoclinic form with space group P21/n. There are two Ni(II) moiety’s in the asymmetric unit. Each nickel atom is five coordination and is chelated by three nitrogen atoms of L and two oxygen atoms of Mal fragments with the formation of a NiN3O2 chelate node. The polyhedron of the first Ni(II) moiety is close to the ideal tetragonal pyramidal structure, while the polyhedron of the second Ni(II) moiety belongs to the distorted tetragonal pyramidal structure. The main stages and kinetics features of the conjugated thermolysis of complex 1 were evaluated. Metal–polymer nanocomposite containing Ni nanoparticles uniformly distributed in a stabilizing nitrogen-containing polymer matrix was obtained.

A nanocomposite based on graphene oxide and copper trimesinate was obtained by the in situ method. The samples have permanent porosity and a microporous structure with a large surface area corresponding to the adsorption type I. A study of the adsorption properties of the obtained composites with respect to organic dyes (malachite green, indigo carmine, brilliant green, Rose Bengal, crystal violet) showed that adsorption largely depends on the content of graphene oxide in the composites. The complex is an effective sorbent for the extraction of cationic and neutral organic dyes when the content of graphene oxide in the nanocomposite is 20% of the calculated copper trimesinate due to electrostatic forces of interaction. For anionic dyes, the maximum adsorption is achieved when using a composite containing 5% graphene oxide due to the predominance of physical sorption. Experimental results show that the obtained sorbent can be used for extraction in a wide pH range, illustrating the excellent pH window offered by this adsorbent. Kinetics data were properly fitted with the pseudo-second-order model. Equilibrium data were best correlated with the Freundlich model. The process was endothermic and spontaneous in nature. The composite makes it possible to achieve a maximum sorption of 393 mg/g, which is a sufficiently high value for the absorption of dyes.

In the present study, a facile and easily accessible method for obtaining copper-containing nanomaterials by thermolysis of copper cinnamate complex with 4′-phenyl-2,2′:6′,2″-terpyridine at 300 °C was developed. The obtained nanomaterials were studied using X-ray diffraction, atomic force microscopy, scanning electron microscopy and energy dispersive analysis. Analysis of copper-containing nanomaterials as additives to lubricant (liquid paraffin) was carried out from the point of view of their tribological behavior using pin-on-disc and four ball friction machines. At optimum concentration of nanomaterials, the friction coefficient is the lowest. The mechanism of friction in the presence of the studied lubricant compositions is discussed.

The reaction between copper(II) acrylate and 4′-phenyl-2,2′:6′,2″-terpyridine resulted in a new metal-containing monomer 1, which was characterized by elemental analysis, FTIR spectroscopy, and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in triclinic form with space group P-1. The chelate node of complex 1 is close to an ideal tetragonal pyramidal structure and includes three nitrogen atoms of the terpyridine ligand and two oxygen atoms of acrylate fragments. Medium-strong hydrogen bond interactions lead to infinite 1D chains. The kinetic and thermodynamic parameters of the thermolysis process of complex 1 were studied. As a result of thermolysis process, nanomaterials of the Cu@C core-shell type were obtained. The resulting nanomaterials are effective antiwear and antifriction additives for lubricating oils.

One of the modern areas of research in analytical chemistry is the development and use of new materials with higher selectivity and improved analytical performance in both sample preparation and separation science. Among them, metal‐organic frameworks (MOFs) are a potential alternative to current commercially available materials. Given the outstanding properties of MOFs and their ability to interact with various compounds, there has been an increasing number of studies in recent years showing their usefulness as sorbents in solid extraction (SPE) schemes. This review article aims to summarize the most recent (over the past 5 years) applications of MOFs in SPE of organic dyes. Particular attention has been paid to provide an overview of the MOF performance enhancement strategies currently being developed in this area. These include increasing the water stability of MOFs, functionalization of MOFs, defect engineering, design of charged MOFs, and modulation of non-covalent interactions. The issues of using MOF in the separation of specific dyes and in the analysis of real objects are considered. The ways of further research in the field of using MOF in SPE of organic dyes are outlined.

A B S T R A C TIn the present work, the interaction of cobalt(II) acetate with 2-iodoterephthalic acid and 1,10-phenanthroline (phen) in N,N-dimethylformamide (DMF) was studied. The reaction leads to the formation of two products: hexa­kis­(N,N-di­methyl­formamide-κO)cobalt(II) bis­­(iodide) (compound 1) and MOF [Co(TP)(phen)·2DMF·2H2O] (compound 2), where TP is terephthalate dianion. Compound 1 crystallizes in the monoclinic space group Р2 1/с with cell parameters a = 14.2974(4) A, b = 10.7983(4) A, c = 20.6437(9) A, V = 3183.23 A3. The MOF was characterized by elemental analysis, infrared spectrometry, X-ray diffraction, scanning electron microscopy, thermogravimetry and volumetric nitrogen adsorption/desorption. The sample has permanent porosity and a microporous structure with a large surface area corresponding to the adsorption type I. Thermolysis of MOF leads to the formation of nitrogen-doped carbon nanomaterials Co/CoO@C.

Several important synthesis pathways for metal-organic frameworks (MOFs) were applied to determine how the synthesis methods and conditions affect the structure and adsorption capacity of the resulting samples. In the present work, three different synthesis routes were used to obtain copper trimesinate coordination polymer: Slow evaporation (A), solvothermal synthesis using a polyethylene glycol (PEG-1500) modulator (B), and green synthesis in water (C). This MOF was characterized by elemental analysis, infrared spectrometry, X-ray diffraction, scanning electron microscopy, thermogravimetry and volumetric nitrogen adsorption/desorption. The samples have permanent porosity and a microporous structure with a large surface area corresponding to the adsorption type I. The obtained MOF was tested as a sorbent to remove organic dyes methylene blue (МВ), Congo red (CR) and methyl violet (MV) as examples. Dye adsorption followed pseudo-first-order kinetics. The equilibrium data were fitted to the Langmuir and Freundlich isotherm models, and the isotherm constants were determined. Thermodynamic parameters, such as changes in the free energy of adsorption (&Delta, G0), enthalpy (&Delta, H0), and entropy (&Delta, S0), were calculated. Thermolysis of copper trimesinate leads to the formation of carbon materials Cu@C with a high purity.

Metal chelate monomers (MCMs) have been widely used as precursors for the production of advanced functional polymers and nanomaterials. In this articel, new metal chelate monomers based on nickel(II) cinnamate (cinn) and various chelating N-heterocycles, [Ni(cinn)2(bpy)(C2H5OH)] and [Ni(cinn)2(phen)(C2H5OH)2] (bpy = 2,2′-bipyridine and phen = 1,10-phenanthroline), were first synthesized and characterized. A detailed analysis of the main stages and features of the kinetics of thermolysis of MCMs was carried out. Metal-polymer nanocomposites with a core-shell structure containing metal nanoparticles evenly distributed in a stabilizing nitrogen-containing polymer matrix were obtained by thermolysis at 300 °C. Thermolysis at 450 °C resulted in pure nickel oxide nanoparticles. The nature of the ligand has been shown to affect the structure and size of the product obtained. The tribological characteristics of nanoparticles as additives to lubricating oils were studied using the pin-on-disc tribometer. At the optimum concentration of nanoparticles, the coefficient of friction is the smallest, and an increase in the concentration above the optimum level leads to an increase in the coefficient of friction.