Applied Organometallic Chemistry最新文献

Hexavalent chromium (Cr(VI)) has attracted great considerations due to their high toxicity, teratogenicity, and carcinogenicity. In this study, four Zr-MOFs were synthesized and used to comparative study their catalytic performances of oxalic acid (OA) for Cr(VI) removal. Results showed that the removal efficiency for Cr(VI) was reached 65.91%, 78.64%, 53.58%, and 96.32% by MOF-525, MOF-525(Co), MOF-525(Zn), and MOF-525(Fe) in the presence of OA when the initial Cr(VI) concentration was 100 mg·L⁻¹, respectively. The single-factor experiments for further improving the Cr(VI) removal by MOF-525(Fe)/OA demonstrated that the optimal conditions were OA dosage of 790 mg·L⁻¹, and MOF-525(Fe) dosage of 500 mg·L⁻¹ and pH of 2.0, and the MOF-525(Fe)/OA system could be used to treat Cr(VI)-containing wastewater at concentrations below 50 mg·L⁻¹. Ionic strength studies indicated that Na⁺, K⁺, Mg²⁺, Cl⁻, and SO₄²⁻ had little effect on the catalytic reduction of Cr(VI), while high concentrations of Ca²⁺ (0.10 and 0.25 mol·L⁻¹), NO₃⁻ (0.25 mol·L⁻¹), and PO₄³⁻ (0.25 mol·L⁻¹) had significant inhibition effects. The reusability experiments showed that the stability of MOF-525(Fe) was excellent, and it could be used for potential applications. Based on the results of Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Electron Paramagnetic Resonance spectrometer (EPR), the possible reduction mechanism of Cr(VI) by MOF-525(Fe)/OA system was proposed as follows: The complexation of OA with Fe³⁺ was first complexed to produce Fe²⁺ and CO₂^•−, then Cr(VI) was combined with Zr–O and Fe–O clusters in MOF-525(Fe) to obtain activation energy, and the reduction ability was enhanced at the same time; finally, Cr(VI) obtained electrons from CO₂^•− and was sequentially reduced as Cr(V) and Cr(III).

Fe₃O₄@APIDSO₃H as a novel and magical magnetic nanocatalyst was designed, synthesized, and characterized by different spectroscopic techniques such as Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), energy-dispersive x-ray (EDX), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). The loading percentage of sulfonic acid on the magnetic nano catalyst was calculated using CHNS analysis. Then, the potential use of it was investigated for the synthesis of various coumarins by Pechmann condensation. The corresponding products were synthesized and isolated in 60%–99% yields. The catalyst was recycled and reused for four times without loss in catalytic activity.

Fabricating a highly active and stable nanocatalyst material displays a great concern when constructing a commercially viable ethylene glycol (EG) fuel cell. Herein, nickel oxide nanostructures were grown onto graphite (NO/T) using coprecipitation and calcination protocol at different temperatures. Techniques for XRD, TEM, SEM, and EDX investigations were used to look into the produced crystal planes, shape, and elemental mapping of synthesized nickel oxide nanoparticles. Different NO/T nanocatalyst electroactivities were examined in order to oxidize EG molecules in basic electrolyte. The surface area values of calcined nanostructures at 200°C and 300°C were much higher than those measured at NO/T-400 by 7.62 and 3.71 folds to explain their outstanding performance. Some kinetic information for varied NO/T nanocatalysts was derived including the electron transfer coefficient, rate constant, and surface coverage values. Electron transfer rate constants of 0.1946, 0.3734, 0.0113, and 0.0303 s⁻¹ were calculated at NO/T-200, NO/T-300, NO/T-400, and NO/T-500, respectively. Increased oxidation current densities could be achieved when NO/T nanomaterials were subjected to lowered calcination temperatures. NO/T-200 and NO/T-300 nanocatalysts also displayed decreased E_onset for alcohol oxidation process by 20 and 41 mV in relation to that at NO/T-400. Moreover, chronoamperometric experiments revealed the prevalence of the stable behavior during EG oxidation at these nanostructures, especially for calcined ones at 200°C and 300°C. Much reduced poisoning rates were measured at NO/T-200 (0.171 s⁻¹) and NO/T-300 (0.067 s⁻¹) when contrasted to that at NO/T-500 (0.727 s⁻¹). Increasing the alcohol and supporting electrolyte concentrations was beneficial in improving the charge transfer characteristics of NO/T nanocatalysts as demonstrated by EIS measurements. This study supports the promising activity of NiO nanoparticles onto graphite as anode materials for direct alcohol fuel cells.

One-pot synthesis of acetamides, benzimidazoles, and benzothiazoles are central reactions for synthesizing pharmaceuticals and fine chemicals. Despite tremendous progress in heterogeneous catalysis, the synthesis of these nitrogen-containing compounds still remains challenging. Here, we report an efficient, simple, and cost-effective nitrogen-doped CeO₂-supported Co single-atom catalyst (SAC) (Co/N-CeO₂) enabled synthesis of acetamides, benzimidazoles, and benzothiazoles. As far as we know, this is the first to report that SACs catalyze the synthesis of acetamides, benzimidazoles, and benzothiazoles. Detailed spectroscopic characterization revealed the structure of catalytic center. Harnessing the catalytic activity of SACs, the work offers promising routes for future synthesis of heterocycles.

In this study, a Fe-MOF was synthesized via a coprecipitation procedure and then used as support for stabilizing Ag ions and producing three-dimensional cluster bud Ag₂O@Fe-MOF nanoflower composite (3D CB Ag₂O@Fe-MOF NFC) by microwave irradiation. The synthesized 3D CB Ag₂O@Fe-MOF NFC was applied as a heterogeneous nano-organocatalyst in green and new preparation of naphthopyranopyrimidines via three-component condensation of aryl aldehydes, β-naphthol, and barbituric acids in the solvent-free conditions at 100°C. Convenience, solvent-free conditions, good yield, and short reaction time make this strategy a promising candidate compared to other methods. The reusability and high efficiency of this catalyst four times without any notable loss of its activity makes this strategy attractive for large-scale eco-friendly applications.

The design, synthesis, and spectroscopic characterization of [Ag(P(o-C₆H₄OCH₃)₃)(NO₃)]₂ (1) and [Ag(P(o-C₆H₄OCH₃)₃)₂][NO₃] (2) were conducted to investigate the efficiency of the fabricated solar cell devices. The slow evaporation technique proved effective in growing the colorless crystals of the silver(I) complexes. Spectroscopic analyses including Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and ultraviolet–visible (UV–Vis) studies were carried out to elucidate the chemical structure and absorption properties of the compounds. The chemical composition and existence of intermolecular interactions in 1 and 2 were disclosed via the single-crystal x-ray diffraction method. The side-to-side arrangement of molecules in 1 and 2 was evident from the crystal packing analysis, in which the molecules in both compounds were linked together by C–H···O and C–H···π contacts. The silver(I) complexes exhibited maximum absorption wavelength (287–288 nm) within the ultraviolet region, where both compounds had comparable high energy band gap values ranging from 4.15 to 4.16 eV. Moreover, both compounds possess appropriate HOMO–LUMO energy levels that facilitate effective electron injection and dye regeneration processes in dye-sensitized solar cell (DSSC) applications. Photophysical characterization techniques, field-emission scanning electron microscopy (FESEM), and energy-dispersive x-ray (EDX) spectroscopy studies were employed to assess the morphological characteristics and elemental composition of the silver(I) complexes on TiO₂. Compound 2 exceeded 1 in terms of solar cell efficiency, 2 (η = 3.34%) > 1 (η = 0.66%) due to the complex being in ionic form and composed of the mononuclear [Ag(P(o-C₆H₄OCH₃)₃)₂]⁺ cation [NO₃]⁻ anion.

Bi-based organic halides have attracted widespread attention as potential substitutes for lead-based organic halide perovskites and have been explored and applied in many optoelectronic devices. The rational design of organic Bi-based halides is a popular research topic. In this work, we used benzylammonium (BA) cations to synthesize BA₃Bi₂I₉ (BBI) perovskite material and FA₃Bi₂I₉ (FBI, FA [formamidinium]) as control. We observe that the benzene rings in BA cations overlap with each other due to the benzene rings Π-Π conjugation in the crystal structure of BBI, which exhibits large interplanar spacing due to large BA ions. BBI has preferential orientation along the (020) crystal plane. Due to conjugation, scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) mapping images indicate that the surface of the BBI thin film is smoother and more uniform than that of the FBI thin film. We fabricated the device by growing thin films of BBI and FBI on ITO interdigital electrodes. The photodetector based on BBI SC exhibits stability and regularity with turning on/off of the light at different intensities (10, 20, 30, and 40 W m⁻²) and wavelengths (386, 397, 405, and 433 nm). The ultraviolet–visible (UV–vis) absorption and reflection spectrum analysis shows that BBI has a slightly wider bandgap than FBI. This study can provide some ideas for the design Π-Π conjugation in organic metal halides.

In the 21st century, pathogenic deformities contribute significantly to global morbidity and mortality. Our research investigates the antimalarial, antimicrobial, and antioxidant activities of newly synthesized hydrazones and their organotin (IV) complexes, derived from 2-benzoyl-1H-indene-1,3(2H)-dione and 2-phenoxypropanehydrazide/2-(2,4-dichlorophenoxy)propanehydrazide. Structural confirmation was achieved through multinuclear nuclear magnetic resonance (NMR), UV–Vis, IR, HRMS, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM)-energy-dispersive X-ray analysis (EDAX), revealing tridentate coordination of ligands to the tin metal via imine nitrogen and two enolic oxygens, forming a pentacoordinated geometry. The SEM analysis revealed that hydrazone ligand (1) exhibits a rectangular bar-like microstructure, whereas its complex (5) shows a rugged surface with distinct territorial patches. Compounds (5) [Bu₂SnL¹] and (6) [Ph₂SnL¹] stood out with significant bioactivity, with antimalarial IC₅₀ values ranging from 0.54 ± 0.07 to 0.67 ± 0.06 μM and antioxidant IC₅₀ values from 4.39 ± 0.02 to 4.67 ± 0.01 μM. Additionally, compounds (6) [Ph₂SnL¹] and (10) [Ph₂SnL⁴] exhibited the highest antimicrobial activity, with MIC values ranging from 0.0045 to 0.0042 μmol/mL, respectively, comparable to standard drugs. Complementing the experimental data, in silico molecular docking studies were performed on the most effective ligand (1) [H₂L¹] and its phenyl complex (6) [Ph₂SnL¹] with Plasmodium falciparum lactate dehydrogenase, revealing binding energies of −6.0 and −6.9 kcal/mol, respectively, and corroborating the experimental findings. Further, comprehensive absorption, distribution, metabolism, excretion, and toxicity (ADMET) evaluations were performed on each compound to gauge their suitability as drug candidates and potential for toxicity.

Milk, owing to its nutritional value, is a staple commodity in daily life. Ensuring its integrity and authenticity is paramount for researchers and the food industry. To evaluate spoilage and adulteration of milk, we proposed a robust and reliable optical method to guarantee milk quality by utilizing riboflavin as an internal biomarker. By precisely controlling the content of Eu³⁺, Tb³⁺, and Gd³⁺ ions, a two-dimensional ratiometric luminescence lanthanide coordination polymer (Ln-CP) with adjustable emission centers was synthesized for the detection of riboflavin (RF), leveraging a Förster resonance energy transfer (FRET) and photoinduced electron transfer (PET) process. This method demonstrates high sensitivity and selectivity towards RF and has been successfully applied to the detection of RF in both milk and calf serum.

Amid growing environmental concerns and the need for a sustainable future, green synthetic methodologies are gaining popularity for their simplicity and nontoxicity. In pursuit of the eco-friendly synthesis of nanomaterials, the study reports an innovative synthesis of Ag-CuO nanocomposites via the coprecipitation method utilizing Citrus limetta fruit juice extract as the bioreductant and stabilizing agent. The morphological and structural characteristics of the fabricated nanocomposites were evaluated by ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman and Brunauer–Emmett–Teller (BET) analyses. The nanocomposites were crystalline with particle sizes ranging from 15 to 24 nm and exhibited spherical and rod-like shapes. The band gap value and specific surface area of the nanocomposites were found to be 1.5 eV and 25.50 m²/g, respectively. The photoluminescence (PL) analysis and electrochemical studies revealed significant charge separation and effective charge migration behaviour of the nanocomposites, respectively. The nanocomposites effectively catalysed the synthesis of Schiff bases from aryl aldehydes and aromatic amines at room temperature and without solvents. The reactions proceeded in a brief time with excellent product yields, and the nanocatalyst retained its activity for five consecutive cycles. The nanocomposites also efficiently catalysed the photodegradation of Congo red dye under visible light. A significant degradation of 94.33% was attained in 55 min, and the nanocatalyst maintained its efficacy over four consecutive reaction cycles. Moreover, the nanocomposites exhibited notable anticancer properties against the MCF-7 (human breast) cell line, demonstrating a remarkable cytotoxicity rate of 87.79%. The findings highlight the efficacy of the biosynthesized nanocomposites in catalysis, environmental remediation and biological applications.