Applied Organometallic Chemistry最新文献

In this study, cobalt(II) and copper(II) metal–organic frameworks (MOFs) were synthesized using conventional reverse micelle (RM) and ultrasonic-assisted reverse micelle (UARM). The UARM method demonstrated superior efficacy in producing MOFs with improved properties. The CO₂ adsorption properties of the synthesized MOFs were investigated using a volumetric adsorption apparatus. The adsorption isotherms were analyzed using various isotherm models, including Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin. Thermodynamic parameters were calculated to understand the nature of the adsorption process. Based on RSM optimization, the capability of Co-MOF was estimated to be about 8.48 mmol/g. The enhanced adsorption performance was attributed to the efficient surface area, surface properties, and strong interaction between the CO₂ molecules and the MOF surface.

An improved solid-state synthesis method was used to create LiFeO₂ layered oxides. The produced material adopts a cubic system (Fm-3m space group) with a refined cell parameter of a = 4.156(9) Å, as indicated by Rietveld refinement of the crystal structure. A morphological investigation revealed that the sample is composed of small primary particles with sizes ranging from 0.20 to 0.75 μm. IR spectroscopy vibrational analysis revealed the presence of FeO₆ and LiO₆ groups. The compound's semiconductor nature was confirmed when the band gap energy was generated and discovered to be 2 eV. There is a tighter dispersion of localized states within the band gap, as indicated by the obtained Urbach energy (0.39 eV), which presents just 20% from the band gap energy. The material's dielectric characteristics were assessed between 0.1 and 107 Hz in frequency and between 333 K and 523 K in temperature. The presence of both space charge and dipolar polarization is suggested by the real component of the dielectric permittivity, which indicates a high dielectric constant (between 100 and 350) at low frequency. The circuits are made up of constant phase elements (CPE) and bulk resistance R coupled in parallel. Jonscher's law was applied to interpret the frequency-dependent conductivity. The outcomes of the charge transport investigation on LiFeO₂ imply that the layered oxide material possessed a large polaron tunneling (OLPT) paradigm with activation energy E_a of 0.26 eV. Comparing the polaron R_ω (2 < R_ω < 5 Å) optimal hopping length to the Li–O interatomic gap (2.077(9) Å), it is larger. We identified and examined a correlation between the ionic conductivity and the crystal structure.

The conjugation of metal–organic frameworks (MOFs) with covalent organic frameworks (COF), as a catalytically active nanocomposite with integrated properties, is a smart strategy for developing efficient catalytic systems. Herein, we report the design and synthesis of NH₂-Glu-MOF/MT-COF nanocomposite using the integration of glutamate MOF (NH₂-Glu-MOF) and melamine-terephthaldehyde COF (MT-COF) via imine bond connection. The synthesized NH₂-Glu-MOF/MT-COF nanocomposite has been fully characterized using FT-IR, XRD, BET, TEM, FE-SEM, EDX, EDX mapping, TGA, and ICP-OES techniques. Analyses demonstrate that NH₂-Glu-MOF/MT-COF nanocomposite has ideal structural and compositional properties such as good specific surface area (241.631 m² g⁻¹), high pore volume, and high thermal stability (530°C). Because of such unbeatable structural and compositional features, NH₂-Glu-MOF/MT-COF nanocomposite shows much better catalytic activity for the synthesis of a wide library chromeno[4,3-b]quinoline-6-one derivatives than parent materials (NH₂-Glu-MOF or MT-COF). Additionally, NH₂-Glu-MOF/MT-COF nanocomposite demonstrated supreme recyclability during five catalytic cycles.

Axial phthalocyanine compound carrying 4-cumyl phenoxy groups was obtained from the reaction of 4-cumyl phenol with silicon phthalocyanine dichloride (SiPcCl₂). The compound was characterized by ¹H NMR, UV–visible light, FTIR, and mass spectrum. Electronic properties and photochemical properties of the compound were investigated by UV–visible light spectra. Singlet oxygen production capacity for the compound was investigated, and the singlet oxygen production (Φ∆) value was found to be 0.14. The sensor potential of the compound was investigated by UV–visible light spectra against magnesium (II) ions (Mg²⁺), manganese (II) ions (Mn²⁺), sodium (I) ions (Na⁺), nickel (II) ions (Ni²⁺), zinc (II) ions (Zn²⁺), silver (I) ions (Ag⁺), barium (II) ions (Ba²⁺), cadmium (II) ions (Cd²⁺), copper (II) ions (Cu²⁺), cobalt (II) ions (Co²⁺), and iron (III) ions (Fe³⁺). The selective sensitivity of the phthalocyanine compound only to Fe³⁺ ions enables the practical analysis of Fe³⁺ ions in many environments. This study presents an alternative and practically applicable method for the sensitive determination of Fe³⁺ ions, which have widespread adverse effects on the environment, ecosystem and human health.

The biogenic silver nanoparticles manufactured using pomegranate as a supporting material are described in this study. The plant's leaves effectively stabilized the produced silver nanoparticles (Ag NPs) and acted as a natural reducing agent. The physicochemical characteristics of the prepared NPs were examined using TEM, EDX, FE-SEM, and UV–Vis methods. According to the study's data, the antioxidant properties of nanoparticles may be related to how well they treat thyroid cancer in humans. The capacity of biologically produced nanoparticles to prevent thyroid cancer cells was assessed. As determined by the MTT assay, the silver nanoparticles had strong anti-thyroid cancer characteristics, effectively eliminating the BCPAP cancer cell in a way that depended on both concentration and time. Ag NPs decrease the anti-apoptotic marker Bcl-2 level while promoting cell death, which is associated with increased levels of pro-apoptotic indicators such as cleaved caspase-8 and Bax. Additionally, compared to the corresponding control group, silver nanoparticles show a reduction in colony development. The data of Ag NPs showed that p53 expression was much higher, and that the examined cell lines had lower levels of signal transducer and activator of transcription 3 (STAT3). This implies that the pomegranate extract-induced biological reactions in BCPAP human thyroid cancer cells depend critically on STAT3 and p53.

In this work, a novel fluorescent chemosensor 3-(2-(2-(4-(diphenylamino)phenyl)-4,5-diphenyl-1H-imidazol-1-yl)thiazol-4-yl)-2H-chromen-2-one (TCCM) was effectively synthesized and characterized through NMR and Mass spectrum. An approach towards the recognition of Cu²⁺ and Co²⁺ ions using a turn-off fluorescence technique was developed. The chemosensor TCCM also exhibited colorimetric and fluorometric sensing behaviour with a visible colorimetric response to trifluoroacetic acid (TFA). Upon the addition of TFA to TCCM, a new peak formation at 500 nm in the absorption spectra along with the visible colour change from colourless to brown. In addition, it exhibits high selectivity towards Cu²⁺ and Co²⁺ ions with a limit of detection of 4.2 and 3.9 μM, respectively. It was discovered that the sensor was quite selective for Cu²⁺ and Co²⁺ ions that had a lot of competing ions. Further, the studies were supported by DFT analysis and NBO studies.

Novel water-soluble Ni(II), Cu(II), Mn(II), and Ce(III) complexes of sodium 4-hydroxy-3-((2-picolinoylhydrazineylidene)methyl)benzenesulfonate ligand (NaH₂PH) were synthesized and characterized by the different analytical methods and spectroscopic techniques as well as magnetic measurements. The chemical structures of the studied chelates were supported by computational studies using DFT calculation. The ligand acts as a mono-negative tridentate (ONN) ligand in the copper (II) complex by (C=N)_py, (C=N)_az, and the deprotonated enolic oxygen atom (C-O). In [Mn₂(NaPH)Cl₂(H₂O)₂] complex, NaH₂PH ligand acts as a bi-negative tetradentate (ONNO) ligand via deprotonated (OH)_phenolic and (C=N*) groups around the first Mn (II), the (HO)_enolic, and (C=N)_az groups coordinated to another Mn(II). As a mono-negative bidentate (ON) ligand, the NaH₂PH ligand functions in the [Ni(NaHPH)Cl(H₂O)]·3H₂O complex. The ligand functions as a bi-negative tetradentate (ONNO) ligand in the [Ce(NaPH)Cl(H₂O)]·3H₂O complex. The isotropic shape of the ESR spectrum of [Cu(NaHPH)(H₂O)₂Cl].H₂O complex confirmed the octahedral geometry around the copper(II) ion. The voltammogram of the Cu(II) and Mn(II) ions exhibited two oxidation and two reduction waves. The antiradical potencies discovered have good radical scavenging activities against ABTS and DPPH radicals. Antimicrobial activities of the isolated complexes have been assessed against selected microorganism. According to the molecular docking studies, the Mn(II) complex shows higher interaction against MCF-7 (PDB ID: 3W2S), which has a good agreement with experimental data.

The removal of dyes from wastewater using stable adsorbents is well documented in numerous scientific reports. Therefore, this study aimed to evaluate a composite of graphitic carbon nitride nanosheet (g-C₃N₄NS) and the biopolymer alginate for the removal of Congo red (CR) dye from aqueous media. To address the challenges associated with the independent use of calcium alginate and g-C₃N₄NS in water, particularly regarding recovery issues, silica-coated magnetic nanoparticles (SMNPs) were incorporated into the composite. To achieve this objective, an alginate-based bioadsorbent was synthesized by crosslinking sodium alginate with calcium chloride in the presence of g-C₃N₄NS and SMNPs using an in situ method. Structural characterization was conducted using BET, TGA, TEM, FE-SEM, and EDX-Mapping analyses. Subsequently, the bioadsorbent was utilized to remove CR dye. The influence of various parameters, including initial concentration, contact time, adsorbent dosage, and pH, was subsequently investigated. According to the isotherm models, the linear Langmuir model exhibited a good fit to the experimental data for CR, indicating a maximum adsorption capacity of 68.03 mg g⁻¹ at pH 5 within 120 min. The synthesized composite has the potential to pave the way for novel applications in both organic and inorganic transformations, as well as in the physical or chemical remediation of diverse pollutants.

Persimmon tannin (PT) was immobilized onto CoFe₂O₄@SiO₂ microspheres to create a novel core–shell nanostructured magnetic bioadsorbent. The as-designed CoFe₂O₄@SiO₂@PT was used to recover Au(III) ions. The bioadsorbent synthesis was performed with different reaction times of 2, 4, 6, 12, and 24 h with a PT to magnetic core weight ratio of 0.8, 1.0, 1.2, 1.5, and 2.0. The profile of Au(III) adsorption by the material in aqueous medium was investigated in a batch system. XRD, FTIR, TEM, thermal analysis, and VSM were used to analyze the materials. The adsorption experiments were conducted in a pH 5 medium, with an adsorbent weight of 5.0 mg and an Au(III) ion concentration of 200 mg/L. The XRD shows that the material is crystalline and retains its structure during the modification. The FTIR data suggest that the material contained expected functional groups. As indicated by the VSM data, it maintains magnetic properties with a range of 12.76 to 17.45 emu/g. The Au(III) adsorption mechanism by the CoFe₂O₄@SiO₂@PT adsorbent was realized by electrostatic interaction and complex formation followed by the reduction of the ions. The maximum Au(III) adsorption capacity was recorded to be 393.34 mg/g.

In this study, ZnO/α-Fe₂O₃ nanocomposites were synthesized via a green coprecipitation method using Hydrocotyle umbellata leaf extract as a reducing and stabilizing agent. The synthesis involved Zn (NO₃)₂.6H₂O, ferric chloride, and sodium hydroxide in various molar ratios of ZnO/α-Fe₂O₃ (9:1, 8:2, 7:3), followed by calcination at 400°C. The synthesized nanocomposites were analyzed using XRD, FTIR, UV-Vis, and SEM to determine their crystalline structure, functional groups, optical properties, and surface morphology. The XRD analysis confirmed the formation of ZnO and α-Fe₂O₃ phases, whereas FTIR confirmed the presence of metal-oxygen bonds and phenolic compounds from the plant extract. UV-vis analysis showed a redshift in the absorption spectra, indicating a reduction in bandgap energy in ZnO/α-Fe₂O₃ nanocomposites compared to pure ZnO. The SEM results confirmed that the ZnO/α-Fe₂O₃ composites exhibit excellent crystallinity, with an average crystal size of approximately 39 nm, calculated using the Debye–Scherrer equation. The antimicrobial activity of ZnO/α-Fe₂O₃ nanocomposites was evaluated using the disk diffusion method against Staphylococcus aureus, Escherichia coli, and Aspergillus niger. The ZnO/α-Fe₂O₃ (8:2) formulation showed the strongest antibacterial effect against S. aureus, highlighting its potential for eco-friendly antimicrobial applications.