Inorganics, Volume 10, Issue 10 (October 2022) – 30 articles

Herein, we report the synthesis of platinum(II) complex bearing 3′-aminothiocyclohexanespiro-5′-hydantoin as ligand. The complex was characterized by IR, NMR spectral analyses, elemental analyses and density functional theory (DFT) calculations. Cytotoxicity and inhibitory potential on xanthine oxidase (XO) were evaluated by performed docking calculations. The cytotoxic activities of the 3′-aminothiocyclohexanespiro-5′-hydantoin (1), its Pt(II) complex (2), thiocyclohexanespiro-5′-hydantoin (3), and its platinum complex (4) were assessed against HL-60 and MDA-MB-231 cells in comparison with the antiproliferative activity of cisplatin as a referent. The ligands (1 and 3) did not exhibit in vitro antitumor efficacy on either of the human tumor cell lines. Complex 2 showed higher antitumor activity (IC₅₀ = 42.1 ± 2.8 μM on HL-60 and 97.8 ± 7.5 μM against MDA-MB-231 cells) than complex 4 (IC₅₀ = 89.6 ± 2.8 μM on HL-60 and 112.5 ± 4.2 μM in MDA-MB-231 cells). IC₅₀ values of cisplatin as referent were 8.7 ± 2.4 μM on HL-60 and 31.6 ± 5.4 μM on MDA-MB-231 cell lines. The inhibitory activity of ligands and complexes against XO, evaluated in vitro, were compared with allopurinol (IC₅₀ = 1.70 ± 0.51 μM) as standard inhibitor. The platinum(II) complexes (2 and 4) inhibited the activity of XO, with IC₅₀ values 110.33 ± 26.38 μM and 115.45 ± 42.43 μM, respectively, while the ligands 1 and 3 did not show higher degrees of inhibition at concentrations lower than 150 μM. The inhibitory potential against XO might be a possible precedent resulting in improved profile and anticancer properties. Full article

Tuberculosis (TB) remains the leading cause of death due to a single pathogen, accounting for 1.5 million deaths annually on the global level. Mycobacterium tuberculosis, the causative agent of TB, is persistently exposed to stresses such as reactive oxygen species (ROS), reactive nitrogen species (RNS), acidic conditions, starvation, and hypoxic conditions, all contributing toward inhibiting bacterial proliferation and survival. Iron–sulfur (Fe-S) clusters, which are among the most ancient protein prosthetic groups, are good targets for ROS and RNS, and are susceptible to Fe starvation. Mtb holds Fe-S containing proteins involved in essential biological process for Mtb. Fe-S cluster assembly is achieved via complex protein machineries. Many organisms contain several Fe-S assembly systems, while the SUF system is the only one in some pathogens such as Mtb. The essentiality of the SUF machinery and its functionality under the stress conditions encountered by Mtb underlines how it constitutes an attractive target for the development of novel anti-TB. Full article

In this study, nano-sized individual Tb₂O₃ particles synthesized by the laser ablation method were extensively characterized and assessed as suitable precursors for the fabrication of transparent magneto-optical ceramics without requiring the introduction of grain growth inhibitors and stabilizing additives. The as-produced powder comprised 13 nm particles with a spherical shape and monoclinic crystal structure, whose full transformation into cubic phase was achieved after heating at 950 °C and 700 °C under vacuum and Ar gas, respectively. After subjecting the nanopowder compact to pre-sintering at 1350 °C, the microstructural features were investigated along with their correlation to the optical transmittance of Tb₂O₃ ceramic hot isostatically pressed (HIPed) for 2 h at 1450 °C under 200 MPa. The as-HIPed sample had a brownish color, with an optical transmittance of 65.3% at a wavelength of 1060 nm and an average grain size of 14 μm. The Verdet constant measured at wavelengths of 633 nm and 1060 nm was 471 rad T⁻¹ m⁻¹ and 142 rad T⁻¹ m⁻¹ to confirm a very high content of magneto-active Tb³⁺ ions. The obtained results indicate that laser ablation synthesis of nanoparticles followed by pre-sintering and HIP is a promising approach for the manufacture of magneto-optical Tb₂O₃ ceramics without specific sintering aids. Full article

Two antimony complexes {[Sb(L¹)Cl₂] C1 and [Sb(L²)Cl₂] C2} with the thiosemicarbazone ligands {HL¹ = 4-(2,4-dimethylphenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide and HL² = 4-(2,5-dimethoxyphenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide} were introduced. The structures were elucidated on the basis of a CHNS analysis, spectroscopic techniques (UV-Vis and FT-IR), and DMF solution electrical conductivities. Single crystal X-ray diffraction analysis of complex C1 assigned the complex pseudo-octahedral geometry and triclinic P-1 space group. Only the ligand HL¹ and its derived complex C1 displayed antifungal activities against Candida albicans and this activity was enhanced from 10 mm to 21 mm for the respective complex, which is the same activity given by the drug “Amphotericin B”. The ligands HL¹ and HL² gave inhibitions, respectively, of 14 and 10 mm against Staphylococcus aureus and 15 and 10 mm against Escherichia coli; however, complexes C1 and C2 increased these inhibitions to 36 and 32 mm against Staphylococcus aureus and 35 and 31 mm against Escherichia coli exceeding the activities given by the ampicillin standard (i.e., 21 mm against Staphylococcus aureus and 25 mm against Escherichia coli). Against MCF-7 human breast cancer cells, the IC₅₀ values of HL¹ (68.9 μM) and HL² (145.4 μM) were notably enhanced to the values of 34.7 and 37.4 μM for both complexes, respectively. Further, the complexes induced less toxicity in normal BHK cells (HL¹ (126.6 μM), HL² (110.6 μM), C1 (>210.1 μM), and C2 (160.6 μM)). As a comparison, doxorubicin gave an IC₅₀ value of 9.66 μM against MCF-7 cells and 36.42 μM against BHK cells. Full article

Anti-reflective coating (ARC) layers on silicon (Si) solar cells usually play a vital role in the amount of light absorbed into the cell and protect the device from environmental degradation. This paper reports on the thickness optimization of hafnium oxide (HfO₂) as an ARC layer for high-performance Si solar cells with PC1D simulation analysis. The deposition of the HfO₂ ARC layer on Si cells was carried out with a low-cost sol-gel process followed by spin coating. The thickness of the ARC layer was controlled by varying the spinning speed. The HfO₂ ARC with a thickness of 70 nm possessed the lowest average reflectance of 6.33% by covering wavelengths ranging from 400–1000 nm. The different thicknesses of HfO₂ ARC layers were used as input parameters in a simulation study to explore the photovoltaic characteristics of Si solar cells. The simulation findings showed that, at 70 nm thickness, Si solar cells had an exceptional external quantum efficiency (EQE) of 98% and a maximum power conversion efficiency (PCE) of 21.15%. The thicknesses of HfO₂ ARC considerably impacted the photovoltaic (PV) characteristics of Si solar cells, leading to achieving high-performance solar cells. Full article

The Er_1.5Y_1.5Al₅O₁₂ (Er:YAG) and (Er_1.43Y_1.43Sc_0.14)(Sc_0.24Al_1.76)Al₃O₁₂ (Er:YSAG) ceramics have been characterized using the Judd-Ofelt (JO) theory. The line strengths and oscillator strengths of several transitions from the ground state ⁴I_15/2 to excited state manifolds have been evaluated from transmittance spectra measured at room temperature (300 K). The JO parameters have been calculated, and the values of the radiative decays rate and the radiative lifetimes for the ⁴I_13/2 excited state, and the luminescence cross-section of ⁴I_15/2 → ⁴I_13/2 in Er-doped ceramic samples have been established. We have traced the influence of Sc³⁺ inclusion on spectroscopic properties and crystal quality and estimate prospects of application in laser systems. Full article

Providing safe drinking water and clean water is becoming a more challenging task all around the world. Although some critical issues and limits remain unsolved, implementing ecologically sustainable nanomaterials (NMs) with unique features, e.g., highly efficient and selective, earth-abundance, renewability, low-cost manufacturing procedures, and stability, has become a priority. Carbon nanoparticles (NPs) offer tremendous promise in the sectors of energy and the environment. However, a series of far more ecologically friendly synthesis techniques based on natural, renewable, and less expensive waste resources must be explored. This will reduce greenhouse gas emissions and harmful material extraction and assist the development of green technologies. The progress achieved in the previous 10 years in the fabrication of novel carbon-based NMs utilizing waste materials as well as natural precursors is reviewed in this article. Research on carbon-based NPs and their production using naturally occurring precursors and waste materials focuses on this review research. Water treatment and purification using carbon NMs, notably for industrial and pharmaceutical wastes, has shown significant potential. Research in this area focuses on enhanced carbonaceous NMs, methods, and novel nano-sorbents for wastewater, drinking water, groundwater treatment, as well as ionic metal removal from aqueous environments. Discussed are the latest developments and challenges in environmentally friendly carbon and graphene quantum dot NMs. Full article

The most well-known, effective medicines for acne therapy are clindamycin phosphate and tretinoin. For the first time, we have developed and validated a reversed-phase HPLC stability-indicating technique for the detection of clindamycin phosphate (CLP), tretinoin (TRN), and two preservatives, methylparaben (MP) and imidazolidinyl urea (IU), simultaneously in this work. Most of the chromatographic conditions in the present study were optimized to achieve better separation. The best separation results were obtained using gradient elution on a C-18 (250 × 4.6 mm), 5 µm column, with a mobile phase consisting of solution A (1 mL/L ortho-phosphoric acid in water) and solution B (methanol), at a flow rate of 1.0 mL/min, with UV detection at wavelengths of 200 nm and 353 nm. Standard parameters such as system suitability, precision, accuracy, specificity, robustness, linearity, range, detection limit, quantification limit, and reagent stability were used to validate the developed technique. According to the standards of the International Council for Harmonization, all of the experimental parameters were found to be within allowable bounds (ICH). The simultaneous concentrations of clindamycin phosphate, tretinoin, methylparaben, and imidazolidinyl urea in pharmaceutical formulations were successfully determined using the suggested approach. The proposed RP-HPLC method detected no interfering peaks in the chromatogram. We may conclude from the data that the new RP-HPLC method can be utilized in pharmaceutical laboratories to simultaneously assess clindamycin phosphate, tretinoin, and two preservatives, methylparaben and imidazolidinyl urea, for both qualitative and quantitative analyses. Full article

The large volume expansion and self-locking phenomenon of metal hydride particles during hydrogen sorption often leads to a high stress concentration on the walls of a container, which may cause the collapse of the container. In present study, silicone oil was investigated as a glidant for a V-based BCC metal hydride bed to alleviate the stress concentration during hydrogen sorption. The results indicated that the addition of 5 wt% silicone oil slightly reduced the initial hydrogen storage capacity of V₄₀Ti₂₆Cr₂₆Fe₈ (particle size: ~325 μm) but improved the absorption reversibility, regardless of the oil viscosity. It was observed that silicone oil formed a thin oil layer of 320~460 nm in thickness on the surface of the V₄₀Ti₂₆Cr₂₆Fe₈ particles, which might improve the fluidity of the powder, reduce the self-locking phenomenon and alleviate the stress concentration on the container walls. Consequently, the maximum strain on the surface of the hydrogen storage container decreased by ≥22.5% after adding 5 wt% silicone oil with a viscosity of 1000 cSt. Full article

Chloranilic acid (2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone, caH₂) as a bidentate ligand for Nb(V) as a metal center is presented. The different coordination behavior of caH₂ is well illustrated by a monomeric (Et₄N)cis-[NbO(ca)₂(H₂O)OPPh₃]·3H₂O.THF (5) and a novel tetranuclear compound (Et₄N)₄[Nb₄O₄(ca)₂(μ²-O)₂Cl₈]·2CH₃CN (6) via self-assembly, respectively. These were obtained in >80% yields and characterized by IR, UV/Vis and NMR (¹H, ¹³C{¹H}, ³¹P{¹H}) spectroscopy and single crystal X-ray diffraction, and they included a systematic assessment of the solid-state behavior. The anionic metal complexes showed different coordination modes at the Nb(V): [Nb₄O₄(ca)₂(μ²-O)₂Cl₈]⁴⁻ (6a; distorted octahedral) and cis-[NbO(ca)₂(H₂O)(OPPh₃)]⁻ (5a; D_5h distorted pentagonal bipyramidal), respectively. The tetranuclear complex 6a is substitution inert, while cis-[NbO(ca)₂(H₂O)OPPh₃]⁻ (5a) allowed a systematic ligation kinetic evaluation. The substitution of the coordinated triphenylphosphine oxide by a range of pyridine-type entering nucleophiles, 4-N,N-dimethyl-aminopyridine (DMAP), pyridine (py), 4-methylpyridine (4Mepy), 3-chloropyridine (3Clpy) and 3-bromopyridine (3Brpy) in acetonitrile at 31.2 °C was carefully evaluated. The subtle interplay between the main group ligand systems and the hard, early transition metal Nb(V) complex (5a) was well illustrated. The entering monodentate ligands showed a 15-fold reactivity range increase in the order 3Brpy < 3Clpy < 4Mepy < py < DMAP in broad agreement with the Brønsted-donating ability of the nucleophiles. The activation parameters determined for the reaction of 5a with DMAP as the entering ligand yielded ΔH^≠_kf = 52 ± 1 kJ mol⁻¹ and ΔS^≠_kf = −108 ± 3 J K⁻¹ mol⁻¹ for the enthalpy and entropy of activation, respectively, indicating an associative substitution mechanism. The study presents an important contribution to the structure/reactivity relationships in Nb(V) complexes stabilized by chloranilic acid as a bidentate ligand. Full article

In the present study, a nanocrystalline Ni-Fe matrix with reinforced TiO₂ nanoparticles as a functional nanocomposite material was fabricated by pulsed current electroforming in UV-LIGA (lithography, electroplating, and molding). The influences of TiO₂ nanoparticles on the Ni-Fe nanocomposite deposition were also investigated using scanning electron microscopy, transmission electron microscopy, and in vitro cytotoxicity assay. It was found that the Ni-Fe nanocomposite with 5 wt.% TiO₂ nanoparticles showed a smooth surface and better dispersion property. When the Ni-Fe nanocomposite is combined with 20 wt.% TiO₂, it resulted in congeries of TiO₂ nanoparticles. In addition, TiO₂ nanoparticles possessed better dispersion properties as performed in pulse current electrodeposition. The microstructure of the electrodeposited Ni-Fe-TiO₂ nanocomposite was a FeNi3 phase containing anatase nano-TiO₂. Moreover, the electrodeposited Ni-Fe-5 wt.% TiO₂ nanocomposite exhibited a smooth surface and structural integrity. Cytotoxicity assay results also proved that the Ni-Fe nanocomposite with different concentrations of TiO₂ nanoparticles had good biocompatibility. Therefore, the optimization of pulse current electroforming parameters was successfully applied to fabricate the Ni-Fe-TiO₂ nanocomposite, and thus could be used as an endodontic file material for dental applications. Full article

The FTO/ITO transparent conductive films currently used in photoelectrochemical devices limit performance improvement due to their low conductivity, poor flexibility, and inability to transmit UV light. Ag nanowire-based films are a very promising alternative to address these problems, and are considered to be the next generation in transparent conductive film. Here, we prepared a cross-linked nano-network composed of ultra-long Ag nanowires by a special physical template method. The obtained Ag nanowire transparent conductive film has a transmittance of over 80% in a wide range of 200 nm–900 nm, a sheet resistance as small as 5.2 Ω/sq, and can be easily transferred to various substrates without damage. These results have obvious advantages over Ag nanowire films obtained by traditional chemical methods. Considering the special requirements of photoelectrochemical devices, we have multifunctionally enhanced the film by a TiO₂ layer. The heat-resistant temperature of transparent conductive film was increased from 375 °C to 485 °C, and the mechanical stability was also significantly improved. The presence of the multifunctional layer is expected to suppress the carrier recombination in self-powered photoelectrochemical devices and improve the electron diffusion in the longitudinal direction of the electrode, while serving as a seed layer to grow active materials. The high-quality Ag nanowire network and functional layer synergize to obtain a UV–Visible transparent conductive film with good light transmittance, conductivity, and stability. We believe that it can play an important role in improving the performance of photoelectrochemical devices, especially the UV devices. Full article

Six new three-dimensional metal–organic frameworks based on early lanthanide(III) cations and trans-1,4-cyclohexanedicarboxylic acid (H₂chdc) were obtained. Their crystal structures were determined by single-crystal X-ray diffraction analysis. The structure of [La₂(H₂O)₄(chdc)₃]·2DMF·H₂O (1; DMF = N,N-dimethylformamide) contains one-dimensional infinite La(III)-carboxylate chains interconnected by cyclohexane moieties to form a highly porous polymeric lattice with 30% solvent accessible volume. Compounds [Ln₂(phen)₂(chdc)₃]·0.75DMF (2_Ln; Ln³⁺ = Ce³⁺, Pr³⁺, Nd³⁺ and Sm³⁺; phen = 1,10-phenanthroline) are based on binuclear carboxylate building blocks, which are decorated by chelate phenanthroline ligands and interconnected by cyclohexane moieties to form more dense isostructural coordination frameworks with primitive cubic pcu topology. Compound [Nd₂(phen)₂(chdc)₃]·2DMF·0.67H₂O (3) is based on secondary building units similar to 2_Ln and contains a coordination lattice isomeric to 2_Ln with a rare hexagonal helical snz topology. Thermal stability and luminescent properties were investigated. For 2_Sm, a strong and nonmonotonous dependence of the luminescence color on the variation of excitation wavelength was revealed, changing its emission from pinkish red at λ_ex = 340 nm to white at λ_ex = 400 nm, and then to yellow at lower excitation energies. Such nonlinear behavior was rationalized in terms of the contribution of several different luminescence mechanisms. Thus, 2_Sm is a rather rare example of a highly tunable monometallic lanthanide-based luminophore with possible applications in light-emitting devices and optical data processing. Full article

Metal-organic frameworks (MOFs) are porous coordination polymers with interesting structural frameworks, properties, and a wide range of applications. A novel 3D cadmium(II)-carboxylate framework, CdMOF ([Cd₂(L)(DMF)(H₂O)₂]_n), was synthesized by the solvothermal method using a tetracarboxylic bridging linker having amide functional moieties. The CdMOF crystal structure exists in the form of a 3D layer structure. Based on the single-crystal X-ray diffraction studies, the supramolecular assembly of CdMOF is explored by Hirshfeld surface analysis. The voids and cavities analysis is performed to check the strength of the crystal packing in CdMOF. The CdMOF followed a multistage thermal degradation pattern in which the solvent molecules escaped around 200 °C and the structural framework remained stable till 230 °C. The main structural framework collapsed (>60 wt.%) into organic volatiles between 400–550 °C. The SEM morphology analyses revealed uniform wedge-shaped rectangular blocks with dimensions of 25–100 μm. The catalytic activity of CdMOF for the solvent and cocatalyst-free cycloaddition of CO₂ into epichlorohydrin was successful with 100% selectivity. The current results revealed that this 3D CdMOF is more active than the previously reported CdMOFs and, more interestingly, without using a co-catalyst. The catalyst was easily recovered and reused, having the same performance. Full article

Inorganic materials with layered perovskite structures have a wide range of physical and chemical properties. Layered perovskites based on BaLa_nIn_nO_3n+1 (n = 1, 2) were recently investigated as protonic conductors. This work focused on the oxygen ion and proton transport (ionic conductivity and mobility) in alkali-earth (Sr²⁺, Ba²⁺)-doped layered perovskites based on BaLa₂In₂O₇. It is shown that in the dry air conditions, the nature of conductivity is mixed oxygen–hole, despite the dopant nature. Doping leads to the increase in the conductivity values by up to ~1.5 orders of magnitude. The most proton-conductive BaLa_1.7Ba_0.3In₂O_6.85 and BaLa_1.7Sr_0.15In₂O_6.925 samples are characterized by the conductivity values 1.2·10⁻⁴ S/cm and 0.7·10⁻⁴ S/cm at 500 °C under wet air, respectively. The layered perovskites with Ruddlesden-Popper structure, containing two layers of perovskite blocks, are the prospective proton-conducting materials and further material science searches among this class of materials is relevant. Full article

One of the global problems is environmental pollution by different biowaste. To solve the problem, biowaste must be recycled. Waste-free technology is also a way of saving exhaustible raw materials. Research on electrochemical energy sources is currently the most dynamically developing area of off-grid energy. Electrochemical capacitors can operate for a long time without changing performance, they have smaller dimensions, high mechanical strength, and a wide operating temperature range. These properties are effective energy-saving devices. Therefore, supercapacitors are widely used in various industries. This review discussed the methods of obtaining and the characteristics of biowaste-derived activated carbon and carbon–manganese oxide (AC-MnO₂)-based supercapacitor electrodes. Full article

Synthetic saponite clay was impregnated with either linear saturated or unsaturated aldehydes through an incipient-wetness deposition approach. To increase the aldehyde loading, saponite was also intercalated with positively charged cetyltrimethylammonium (CTA⁺) species, aiming to expand the clay gallery and to increase the hydrophobic character of the host solid. A multitechnique, physicochemical investigation was performed on the organic–inorganic hybrid solids. The analyses revealed that the aldehydes are mainly adsorbed on the clay particles’ surface, with a small fraction inside the interlayer space. In CTA⁺-modified saponites, the concentration of saturated aldehydes was higher than the one observed in the pure clay. These features are quite promising for the development of novel layered solids containing bioactive molecules for ecocompatible and economically sustainable applications, especially in agriculture, for the development of innovative hybrid materials for crop protection. Full article

It has been shown that the interaction of tris(triphenylphosphine)ruthenium dichloride RuCl₂(PPh₃)₃ (1) with 10-vertex monocarborane [6-Ph-nido-6-CB₉H₁₁]⁻[Et₄N]⁺ (2) under mild thermolysis conditions is not selective due to the undesired coordination of ruthenium to a phenyl substituent in the carborane and phosphine ligands, giving the series of new classical and non-classical metallacarborane complexes. In contrast, the reaction of 1 and monocarborane [arachno-6-CB₉H₁₄]⁻[Et₄N]⁺ (3) proceeds more selectively with the formation of the only one product, a isocloso-structured metallacarborane. The structures of two ruthenacarboranes were resolved by X-ray diffraction. Full article

Pure TiO₂ synthesized by the sol-gel method and subsequently deposited at 5% by weight with Co, Cu, Fe, and Ni ions by the deposition–precipitation method was studied as photocatalysts. The nanomaterials were analyzed by SEM, TEM, UV-Vis DRS, DRX, Physisorption N₂, and XPS. The SEM and TEM images present a semi-spherical shape with small agglomerations of particles and average size between 63 and 65 nm. UV-Vis results show that a reduction below 3.2 eV exhibits a redshift displacement and increment in the optical absorption of the nanoparticles promoting the absorption in the UV-visible region. XRD spectra and analysis SAED suggest the characteristic anatase phase in TiO₂ and deposited materials according to JCPDS 21-1272. The specific surface area was calculated and the nanomaterial Ni/TiO₂ (21.3 m² g⁻¹) presents a slight increment when comparing to TiO₂ (20.37 m²g⁻¹). The information generated by the XPS spectra present the deposition of metallic ions on the support and the presence of different valence states for each photocatalyst. The photocatalytic activity was carried out in an aqueous solution with 80 mg L⁻¹ of 2,4-D or 2,4-DCP under UV light (285 nm) with 100 mg L⁻¹ of each photocatalysts for 360 min. The nanomaterial that presented the best efficiency was Ni/TiO₂, obtaining a degradation of 85.6% and 90.3% for 2,4-D and 2,4-DCP, respectively. Similarly, this material was the one that presented the highest mineralization, 68.3% and 86.5% for 2,4-D and 2,4-DCP, respectively. Photocatalytic reactions correspond to the pseudo-first-order Langmuir–Hinshelwood model. Full article

In this study, four new Secnidazole metal complexes have been synthesized through the reaction of Secnidazole drug with AuCl3, PtCl2, PdCl2, AgNO3 salts. The structures of the synthesized complexes were elucidated using elemental analysis, molar conductivity, thermal analysis, IR, ¹H-NMR and UV-Vis spectroscopy. The spectroscopic results confirm that Secnidazole drug act as a bidentate ligand, coordinated to the metal ion with N3 of the imidazole ring and oxygen atom of OH group. The antimicrobial data revealed that the complexes possess a better antibacterial activity against most of the selected bacteria species than the free drug. In addition, the cytotoxic data showed that Ag-complex possesses a potent anticancer activity against MCF-7 cell line. The docking data showed that the synthesized complexes displayed a good and effective binding model against breast cancer protein (3hb5) which was confirmed by the low values of binding energy and multiple H-bonds. Full article

The electronic structures of four tin-based 0D hybrid perovskites ((NH₃(CH₂)₂C₆H₅)₂[SnCl₆], (C₆H₁₀N₂)[SnCl₆], (C₉H₁₄N)₂[SnCl₆], and (C₈H₁₂N)₂[SnCl₆]) were determined by the DFT method employing the pseudopotential plane wave as implemented in the CASTEP code, and the first transition in each compound has been investigated based on the partial density states and dielectric function. According to the structural properties, incorporating organic cations with the appropriate structure, shape, and strong H-bonding functionality into hybrid perovskite crystals is very beneficial for preventing ion migration and thus enhances the efficiency of hybrid perovskite-based devices. Based on those properties employing the DFT+D method for the dispersion force, the effect of Van der Waals interaction on electronic structure was explained based on the nature of the first electronic transition. The similarity between the experimental and optimized structure was investigated by using a Bilbao crystallographic server. The study of optical properties shows that the Van der Waals interactions have a slight effect on the energy level of the curves. However, the profiles of curves are conserved. The absorption curves of the researched compounds are elaborated. Full article

⁹⁹Mo/^99mTc generators are mainly produced from ⁹⁹Mo of high specific activity generated from the fission of ²³⁵U. Such a method raises proliferation concerns. Alternative methods suggested the use of low specific activity (LSA) ⁹⁹Mo to produce ^99mTc generators. However, its applicability is limited due to the low adsorptive capacity of conventional adsorbent materials. This study attempts to investigate the effectiveness of some commercial metal oxides nanoparticles as adsorbents for LSA ⁹⁹Mo. In a batch equilibration system, we studied the influence of solution pH (from 1–8), contact time, initial Mo concentration (from 50–500 mg∙L⁻¹), and temperature (from 298–333 K). Moreover, equilibrium isotherms and thermodynamic parameters (changes in free energy ΔG⁰, enthalpy change ΔH⁰, and entropy ΔS⁰) were evaluated. The results showed that the optimum pH of adsorption ranges between 2 and 4, and that the equilibrium was attained within the first two minutes. In addition, the adsorption data fit well with the Freundlich isotherm model. The thermodynamic parameters prove that the adsorption of molybdate ions is spontaneous. Furthermore, some investigated adsorbents showed maximum adsorption capacity ranging from 40 ± 2 to 73 ± 1 mg Mo∙g⁻¹. Therefore, this work demonstrates that the materials used exhibit rapid adsorption reactions with LSA ⁹⁹Mo and higher capacity than conventional alumina (2–20 mg Mo∙g⁻¹). Full article

In the present study, the concentration series of MgAl₂O₄:Ce³⁺ ceramics have been fabricated by the Spark Plasma Sintering (SPS) method. Cerium-doping concentration was varied within a range of 0.1–5 wt.%. The prepared ceramics have been tested using the various experimental techniques: X-ray diffraction (XRD), scanning electron microscopy, as well as optical and cathodoluminescence spectroscopy. According to XRD, all synthesized samples are biphasic with structural impurities. The cerium ion concentration effect on the cathodoluminescent characteristics of MgAl₂O₄:Ce³⁺ ceramics has been studied in terms of emission intensity and decay time. Before annealing the concentration, quenching is observed. The optimal doping Ce³⁺ concentration was determined to be 5 wt.% after temperature annealing at 1300 °C. The successfully prepared spinel ceramics could be potentially applying for high-energy electrons detection. Full article

This manuscript is reviewing the superior catalytic activity and selectivity of ferrocene ligands in a wide range of reactions: reduction of ketones, hydrogenation of olefins, hydroboration, cycloaddition, enantioselective synthesis of biaryls, Tsuji–Trost allylation. Moreover, the correlation between a ligand structure and its catalytic activity is discussed in this review. Full article

Reactions between Zn(II) nitrate, pentaiodobenzoic acid (HPIBA) and different pyridines in dimethylformamide (DMF) result in the formation of the heteroleptic neutral complexes [Zn(3,5-MePy)₂PIBA₂] (1) and [Zn(DMF)₃(NO₃)PIBA] (2). Both compounds were isolated in pure form, as shown by the PXRD data. The features of specific non-covalent interactions involving halogen atoms (halogen bonding) were examined by means of DFT calculations (QTAIM analysis and the estimation of corresponding energies). Full article

Cadmium (Cd) contamination in agricultural soils has caused extensive concern to researchers. Biochar with iron-compound modifications could give rise to the synergistic effect for Cd restriction. However, the related capture mechanism based on physicochemical properties is unclear. In this study, first principles calculations are proposed to explore the adsorption ability and potential mechanism of the ferric hydroxide modified graphene (Fe@G) for capturing CdCl₂. The simulation results show that the adsorption energy to CdCl₂ could enhance to −1.60 eV when Fe(OH)₃ is introduced on graphene. Subsequently, analyses of electronic properties demonstrated a significant electron transfer between Cd s-orbital and O p-orbital, thereby leading to strong adsorption energy. This theoretical study not only identifies a powerful adsorption material for Cd reduction in agricultural soils and reveals the capture mechanism of Fe@G for Cd but also provides a foundation and strategy for Cd reduction in agricultural soils. Full article

This article proposes a definition for the term “pnictogen bond” and lists its donors, acceptors, and characteristic features. These may be invoked to identify this specific subset of the inter- and intramolecular interactions formed by elements of Group 15 which possess an electrophilic site in a molecular entity. Full article

A titanium (Ti) commercial cathode material and high purity Ar and O₂ were used in the cathodic arc physical vapor deposition (arc-PVD) process. The TiO_x coating was deposited on the three sets of Raschig rings using decreasing ratios of Ar/O₂:440/60, 400/100 and 300/100. The cross sections of the TiO_x PVD coating were analyzed using field emission scanning electron microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). A homogeneous layer of Ti with small O content was observed, and the data suggest that a thin TiO_x oxide film was deposited. For this reason, a thermal treatment was applied to the coating to oxidize it and form the rutile phase of TiO₂ in the coating, which was demonstrated by grazing incidence XRD. In addition, the TiO_x coatings absorb radiation, which was observed by diffuse reflectance band gap energy measurement. Silver (Ag) was added by the photo-reduction method, using UVC light to activate the TiO₂ coating, and the band gap energy was analyzed by diffuse reflectance. The photocatalytic activities of the films were evaluated by degradation of the model dye rhodamine B and in the removal of fecal coliforms using two matrices, water from a secondary treatment effluent, and synthetic water. Full article

In the reaction of zinc(II) sulfate and the chloride salt of 2-acetylpyridine-aminoguanidine, two types of complex were obtained, i.e., [Zn(H₂O)₆](H₂L)₂(SO₄)₃·3H₂O and [Zn(L)H₂O(SO₄)]·H₂O, depending on the presence of LiOAc as the deprotonating agent. The physicochemical, structural, and photoluminescence properties of the complexes were examined. In the first complex, obtained in the absence of LiOAc, the Schiff base had the role of a counter-ion in its doubly protonated form, while in the presence of LiOAc, upon deprotonation, coordination takes place, and thus the Schiff base acts as a tridentate N₃ ligand. In the latter complex, the ligand is coordinated through pyridine, azomethine, and the imino nitrogen of the aminoguanidine residue, leading to formation of two fused five-membered chelate rings. Both the examined complexes, as well as the ligand itself, show high photoluminescence. Full article

The reaction of ammonium N-methyl-N-phenyl dithiocarbamate with In³⁺ resulted in the In(III) tris (N-methyl-N-phenyldithiocarbamate) complex. The spectroscopic characterization of the complex was carried out using FTIR, ¹H, and ¹³C NMR spectroscopy. Single-crystal X-ray diffraction analysis (SCXRD) revealed that the complex crystallizes in a triclinic system with a centrosymmetric P-1 space group. The stabilization of the structure was via weak hydrogen bonds and C-H···π contacts. The non-covalent interactions in the crystal network were identified using computational analysis based on SCXRD data, such as Hirshfeld surface analysis. The thermal decomposition behaviour of the complex was studied by thermogravimetric analysis, which showed a one-step decomposition to yield In₂S₃ at 380 °C. Full article