Journal of the Iranian Chemical Society最新文献

Two new complexes, [Tl(pyc)]_n (1) and {[Hg(pyc.H)(μ-Br)₂].C₂H₅OH}_n (2) have been synthesized by the reaction of one and two equivalent of pyridine 3-carboxylic acid (pyc.H) ligand with Tl₂(CO₃) (1) and HgBr₂ (2), respectively. The complexes were fully characterized by elemental analysis, UV, FT-IR, FT-NMR and emission spectroscopies and their structures were studied by the single-crystal X-ray diffraction method. According to X-ray analysis, complex 1 (τ₅ = 0.915) exhibit slightly distorted trigonal bipyramidal geometry around Tl(I) and complex 2 (τ_{5 =} 0.062) shows a slightly distorted square pyramidal geometry around Hg(II). There are intermolecular hydrogen bonding (for complexes 1 and 2) and π-π contacts (for complex 2) which play a significant role in the stabilization of the crystal structure. Luminescence studies revealed the emission properties of free ligand and both complexes in solution. Moreover, in this study, density functional theory (DFT) was performed for Tl(I) coordination polymer 1. The optimized geometry of this complex is shown in good agreement by single crystal X-ray data. Molecular properties including bond lengths, bond angles, and HOMO-LUMO energy levels, were analyzed. Moreover, the UV-Vis spectra were analyzed using time-dependent density functional theory (TD-DFT) method. The tendency of the donor-acceptor interactions in the complex 1 was examined using natural bond orbital (NBO) analysis. In addition, the partial density of states (PDOS) calculation indicates that the π-character of the aromatic pyridine ligand plays role in dominating the valence bands with negligible participation of the Tl orbitals.

The peels of pomegranate fruits were employed in the current work to produce activated carbon (AC) using the high temperature carbonization method. The generated activated carbon using pomegranate peel (AC-PP) powder was discovered to have a layered and porous form as revealed by scanning electron microscopic images. It was discovered that activated carbon had an energy gap (E_g) of 4.454 eV. The photocatalytic experiments performed for the degradation of fast blue dye reveal that after 120 min of UV light irradiation, the AC-PP powder achieve a decolorization rate of 62.9%, respectively. Current was collected through the nickel mesh, and the electrochemical elements in rGO, the principal active component in AC-PP powder, were supported by the mesh. Nickel mesh electrodes were analysed using impedance spectroscopy and cyclic voltammetry. Both AC-PP and AC-PP-rGO electrodes' hydrogen diffusion coefficients were determined to be 1.134 10^–4 and 0.0014 cm² s⁻¹, respectively. Experiments with galvanostatic charge–discharge revealed the produced AC-PP and AC-PP-rGO electrodes' superior capacitance potential, which is useful in the fabrication of supercapacitors. The AC-PP and AC-PP-rGO electrodes have 175.6 and 324.8 F g⁻¹ specific capacitances. These unique impacts can also be assessed by energy storage performance using affordable carbon resources in various applications. These novel results might be used for developing up particular resources for environmental and power storage applications.

The inhibition performance and adsorption behavior of an unsymmetrical tridentate Schiff base, 2-(((2-((2-nitrophenyl) thio) phenyl) imino) methyl)phenol (NOS) on mild steel in 2M hydrochloric acid solution has been studied using electrochemical and quantum chemical techniques. The electrochemical outcomes suggest that NOS works as an anodic-type inhibitor. The adsorption process of the NOS Schiff base obeys the Langmuir model. The theoretical evaluation has been performed using DFT calculations to investigate the correlation of effective corrosion inhibition with some NOS Schiff base structural parameters. The obtained results revealed that there was a good agreement between the theoretical and experimental results.

Two L-lysine-derived salicylidene ligands have been synthesized under ultrasound irradiations and characterized by several spectroscopic techniques. Both ligands exhibited a blue fluorescence emission in ethanolic solutions. (S, E)-3-Amino-7-((2-hydroxybenzylidene) amino) heptanoic acid (A) and (S, E)-3-amino-7-((4-chloro-2-hydroxybenzylidene) amino) heptanoic acid (B) showed a turn-off sensing of Cu²⁺ and Co²⁺ cations, respectively, over several tested transition metal cations such as Fe²⁺, Zn²⁺, Cr³⁺, Co²⁺, Ni²⁺ and Cu²⁺ in aqueous media. The ability of both tested L-lysine-derived ligands (A) and (B) to distinguish Cu²⁺ and CO²⁺, respectively, has been verified by optical studies, showing new absorption bands around 304 and 391 nm for (A)-Cu²⁺ and a new band around 455 nm for (B)-Co²⁺ along with the disappearance of the original bands supporting thereby the noticed Turn–Off results.

Graphical abstract

Electrochemical sensors are a class of sensors in which the electrode is the transducer element. In this type of sensor, an electrode is a critical component employed as a solid support for immobilizing biomolecules and electron movement. The material, fabrication approach, and design affect the electrode’s structure and properties, which ultimately determine the biosensor’s performance, including sensitivity, selectivity, limit of detection, and dynamic range. They also influence the biosensor’s cost, manufacturability, disposability, and measurement capabilities. This review article describes recent advances in using non-modified and modified electrodes as support in electrochemical biosensors for the determination of biomolecules. It summarizes recent work on modifying electrodes using carbonaceous materials, conducting polymers, MXenes, and transition metal oxide nanomaterials. It also focuses on current techniques, types of materials, designs, simulation studies, and fabrication methods on unmodified and modified electrodes. Lastly, challenges in electrochemical sensors were identified, and future directions were presented comprehensively.

Graphical Abstract

In the current study, a zirconium-containing anion exchange resin was synthesized as an oxidizing resin for iodide adsorption from aqueous solutions. The static adsorption capacity of the oxidizing resin was 612.86 mg/g (obtained from isotherm studies and the Langmuir model). This capacity was 31% higher than the capacity of counter parent resin for iodide adsorption. Adsorption performance of the oxidizing resin was close to maximal over a wide range of pHs (2–7), and the best results were obtained at pH = 3 (8.5% higher than the resin capacity in neutral pH). Iodide removal selectivity in the presence of three commonly encountered anions ({{text{SO}}}_{4}^{2-}), ({{text{NO}}}_{3}^{-}) and ({{text{Cl}}}^{-}) was improved. The iodide selectivity of oxidizing resin in the presence of ({{text{Cl}}}^{-}) ion was excellent. Breakthrough curves of both resins with and without encountered anions were fitted with common breakthrough curve models. The results were consistent with the results of the batch mood experiments. Pseudo-second-order kinetic was described kinetic behavior of both resins well. An iodide adsorption mechanism was proposed using the results of batch experiments and the resin characterizations (XPS and Raman spectra). The potential of oxidizing resin for iodide oxidation into iodine increased the capacity and selectivity of resin toward iodide ions.

Herein, we reported the construction of hydrogen peroxide (H₂O₂) sensor using calcium titanate modified screen printed electrode (CaTiO₃@SPE). The CaTiO₃ has been synthesized via hydrothermal method using calcium nitrate tetrahydrate and titanium butoxide as the Ca and Ti source. The CaTiO₃ was characterized by many physiochemical techniques such as powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) and scanning electron microscopy (SEM). The XRD analysis revealed the existence of decent crystalline nature in the synthesized material, while EDX results demonstrated its good phase purity. The SEM micrographs suggested that CaTiO₃ has flakes-like surface structure. The BET results also indicated that CaTiO₃ has specific surface area of 57.6 m²/g. Furthermore, CaTiO₃ was used as the electrode material and CaTiO₃@SPE has been constructed using drop-casting method. The fabricated CaTiO₃@SPE was used for the sensing of H₂O₂ using cyclic voltammetry and linear sweep voltammetry methods. The CaTiO₃@SPE exhibited reasonable limit of detection of 0.08 µM with good selectivity, stability and repeatability.

ZnO/Ag nanocomposite was prepared via in situ method by using silver nitrate and ZnSO₄ as the raw material. ZnO and ZnO/Ag were characterized by utilizing SEM, UV-vis, XRD, FTIR, and so on. The photocataytic degradation behaviors of ZnO and ZnO/Ag for trimethylamine (TEA) in air and solution were studied. The results indicated that ZnO/Ag had better photocatalytic degradation properties on trimethylamine under the condition of 0.06 g catalyst, 2 h photocatalytic time, and 15 A light intensity, and the degradation rates of TEA were up to 44 and 67% in air and solution, respectively. Furtherly, ZnO and ZnO/Ag also indicated perfect photocatalytic degradation properties toward to organic compounds in wastewater. Especially, the harmless treatment of triethylamine was achieved by using photocatalytic degradation method that provided a novel method for treating triethylamine. In all the above results leaded to a good application prospect of ZnO/Ag in the degradation of organic compounds in air and solution.