Synthesis, characterization and microstructural evaluation of ZnO nanoparticles by William-Hall and size-strain plot methods

ABSTRACT. At various calcination temperatures 450, 550 and 650 °C, zinc oxide nanoparticles were produced. Calcinated ZnO has high surface area as the BET was 119.12 m2g–1 and the average particle radius was calculated to be 1.16 nm. The dimension of crystallites and straining in ZnO nanoparticles' diffraction peaks remained measured. The Williamson–Hall (W–H) technique besides the size–strain approach stayed used. For each of XRD reflection peaks, physical characteristics like strain and stress were computed. Towards regulate the magnitude of crystallites, the Williamson–Hall (W–H) approach besides the size–strain technique are used that is good agreement with the size that determine from SEM as it was 22.6, 26.6 and 32.6 nm for ZnO calcinated at 450, 550 and 650 oC, individually. Using the W–H plot to modify the subversion shape, assuming an unvarying distortion model (UDM), unvarying stress deformation model (USDM), unvarying deformation energy density model (UDEDM), and The size–strain plan (SSP) approach was used to determine this. The SEM and Scherrer methods match well with the crystal size of ZnO NPs determined using W–H plots and the SSP technique.     KEY WORDS: Zinc oxide nanosphere, Calcination, Physical characterization, W–H investigation, SSP technique Bull. Chem. Soc. Ethiop. 2022, 36(4), 815-829.                                                           DOI: https://dx.doi.org/10.4314/bcse.v36i4.8                                                       &nbsp

A new simple route for synthesis of cadmium(II), zinc(II), cobalt(II), and manganese(II) carbonates using urea as a cheap precursor and theoretical investigation

ABSTRACT. The MnCO3.H2O, CoCO3.4H2O, ZnCO3, and CdCO3, respectively, were synthesized through a new precise, easy pathway for the reaction of MnI2, CoI2, ZnI2, or CdI2 aqueous solutions with a cheap precursor-urea for 10 h at ~ 70 oC. The IR spectra of reaction products designate the presence of characteristic bands of ionic carbonate, CO32– and absence of the individual bands of urea. The (CO3)2- ion is planar and therefore, it belongs to the D3h symmetry. It is expected to display four modes of vibrations. The stretching vibrations of the type; n(C-O) is observed in the range of (1376-1503) cm-1 while another stretching vibration n(C-O) is observed in the region 1060-1079 cm-1. The out of plane of vibration d(OCO) is observed in the range of (833-866) cm-1 while, the angle deformation bending vibration d(OCO) appear in the range of (708-732) cm-1. The infrared spectra of metal carbonate, show that, this product clearly has an uncoordinated water. The band related to the stretching vibration n(O-H) of uncoordinated H2O is observed as expected in the range of ~ 3000 cm-1. A general mechanism explaining the synthesis of carbonate compounds of cadmium(II), zinc(II), cobalt(II), and manganese(II), are described. Moreover, the DFT outcomes using B3LYP/LanL2DZ (basis set) agree with the experimental results.                 KEY WORDS: Carbonate, CoI2, Infrared spectra, Urea, DFT   Bull. Chem. Soc. Ethiop. 2022, 36(2), 363-372.                                                                DOI: https://dx.doi.org/10.4314/bcse.v36i2.10                                                     &nbsp

Efficient adsorption of Rhodamine B using a composite of Fe3O4@zif-8: Synthesis, characterization, modeling analysis, statistical physics and mechanism of interaction

ABSTRACT. The utilization of a metal organic framework (ZIF-8) modified by Fe3O4 nanoparticles was used to accomplish adsorption of Rhodamine B (RB) from aqueous solutions. SEM, XRD, IR, and BET analyses were all used to characterize the composite (Fe3O4@ZIF-8). The surface area of this adsorbent was 478.4 m2/g. X-Ray diffraction spectroscopy was used to detect surface modification utilizing electron microscopy (SEM) scanning with 48 nm in diameter average particle size according to a statistical physics method. Fe3O4@ZIF-8 appears to have dispersive interactions and pore characteristics, according to quantum chemistry simulations. On the adsorption of RB, the influences of contact time, adsorbent quantity, dye concentration, and temperature were studied. The Langmuir and Freundlich adsorption isotherm models were used to study the adsorption isotherms. Anticipated overall adsorption potential was 647.5 mg/g, with a zero-charge point (pHPZC) of 4.3. The adsorption isotherm was fitted using Langmuir whereas pseudo second order was used to match the kinetics. Energy of adsorption (Ea) is 28.7 kJ/mol, indicating a chemisorption phase. The adsorption process is endothermic and unpredictable, according to thermodynamic experiments. It was also looked into using ethanol as a solvent in the desorption of deposited cationic dye.   KEY WORDS: Fe3O4@ZIF-8, Rhodamine B, Adsorption models, Thermodynamics   Bull. Chem. Soc. Ethiop. 2023, 37(1), 211-229.                                                                DOI: https://dx.doi.org/10.4314/bcse.v37i1.17                                                     &nbsp

Anticandidal activity of the extract and compounds isolated from Cyperus conglomertus Rottb

The phytochemical screening of Cyperus conglomeratus showed that carbohydrates and/or glycosides, flavonoids, tannins, sterols and/or triterpenes, and proteins and/or amino acids are present. The fatty acid profile comprised major; palmitic, oleic, heptadecanoic, linoleic and minor; arachidonic, lignoceric, stearic, and myristic acid. Two compounds; namely, α-amyrin and β-sitosterol were isolated by the fractionation of unsaponifiable matter.The acute toxicity study showed that the reported after oral administration of the alcohol extract (TAE) showed that the plant was highly safe as the LD50 was more than 4000 mg/kg. These results were well supported by the sub-chronic toxicity, as the TAE administrated to rats for 15 consecutive days at dose 1000 mg/kg showed no alteration in the liver and kidney functions. Moreover, the extract of the plant exhibited anti-candidal activity against different Candida species. The most potent activity, (23.1 ± 2.1, 0.98 µg/ml) and (22.3 ± 0.53, 0.98 µg/ml), was obtained by the chloroform and total extract, respectively against Candida albicans. Keywords: Cyperus conglomeratus, Phytochemical screening, Antimicrobial activity, Fatty acids, α-amyrin, β-sitostero

Green synthesis of thioxoimidazolidine derivative ligand: Spectroscopic, thermal and biological assignments of new Cu(II), Co(II), and Ni(II) chelates in neutral system

Eco-friendly synthesis of ethyl 3-(4-oxo-3-(1-(pyridin-3-yl)ethylideneamino)-2-thioxoimidazolidin-1-yl)propanoate (4) ligand (L) using microwave irradiation technique was described. The structure of thioxoimidazolidine derivative ligand compound has been established based on different types of analyses such as infrared, 1H-NMR, 13C-NMR, and mass spectra as well as elemental analysis. The copper, cobalt, and nickel(II) complexes with molecular for-mula [M(L)(H2O)4]Cl2 (where M = Co(II), Ni(II), and Cu(II), L = thioxoimidazolidine derivative ligand), have been prepared and well-characterized using microanalytical, conductivity measurements, magnetic, spectroscopic, and physical analyses. Upon the outcome results of analyses, the stoichiometry of the synthesized complexes is 1:1 (M:L). The molar conductance values concluded that the behavior of metal complexes was electrolytes. The 3-(4-oxo-3-(1-(pyridin-3-yl)ethylideneamino)-2-thioxoimidazolidin-1-yl)propanoate chelate acts as a monovalent bidentate fashion via nitrogen and oxygen atoms of both thioxoimidazolidine and propanoate ester moieties. The geometric structures of the synthesized metal complexes are an octahedral confi guration based on spectroscopic and magnetic moment studies. The thermogravimetric assignments deduced that the presence of four coordinated water molecules. The synthesized copper(II), cobalt(II), and nickel(II) complexes were biologically checked against G+ and G- bacteria and two species of fungi (Aspergillus Nigaer, and Penicillium Sp.)

Fe₃O₄-Carbon-Based Composite Derived from the Charge-Transfer Reaction Using Waste Tea Leaves as the Carbon Precursor for Enhanced Removing of Azocarmine G2, Methyl Violet 2B, Eosin B, and Toluidine Blue from Aqueous Solution

Ferric chloride salt (FeCl3) is a typical vacant orbital acceptor that accepts electrons from urea molecules. This donor-acceptor interaction yields a Fe3O4 oxide, which can be used for preparing novel adsorbent material. Activated carbon (AC) materials, derived from biomass precursors and used for environmental remediation, have gained increasing attention owing to their sustainability, eco-friendly nature, ease of fabrication, and cost-effectiveness. Globally, a large amount of consumed tea leaf materials is discarded as solid waste. The present study aimed to reuse consumed tea leaves to generate biomass-derived-ACs and coupling AC with Fe3O4 oxide to generate Fe3O4-carbon-based composite for environmental remediation. The synthesized Fe3O4-carbon-based composite was examined to remove four common organic pollutant dye models from an aqueous solution. The effects of several parameters on the adsorption capacity of the synthesized composite were analyzed, and equilibrium data were examined. We found that the synthesized composite displayed promising adsorption activity against the investigated dyes

Fe3O4-Carbon-Based Composite Derived from the Charge-Transfer Reaction Using Waste Tea Leaves as the Carbon Precursor for Enhanced Removing of Azocarmine G2, Methyl Violet 2B, Eosin B, and Toluidine Blue from Aqueous Solution

Ferric chloride salt (FeCl3) is a typical vacant orbital acceptor that accepts electrons from urea molecules. This donor-acceptor interaction yields a Fe3O4 oxide, which can be used for preparing novel adsorbent material. Activated carbon (AC) materials, derived from biomass precursors and used for environmental remediation, have gained increasing attention owing to their sustainability, eco-friendly nature, ease of fabrication, and cost-effectiveness. Globally, a large amount of consumed tea leaf materials is discarded as solid waste. The present study aimed to reuse consumed tea leaves to generate biomass-derived-ACs and coupling AC with Fe3O4 oxide to generate Fe3O4-carbon-based composite for environmental remediation. The synthesized Fe3O4-carbon-based composite was examined to remove four common organic pollutant dye models from an aqueous solution. The effects of several parameters on the adsorption capacity of the synthesized composite were analyzed, and equilibrium data were examined. We found that the synthesized composite displayed promising adsorption activity against the investigated dyes

Synthesis and spectroscopic interpretations of Co(II), Ni(II) and Cu(II) decxycholate complexes with molecular docking of COVId-19 protease

Co(II), Ni(II) and Cu(II) decxycholate complexes are interesting due to their biologically active and deliberate interest in the research due to their coordination properties. The microanalytical ‘elemental analysis’, molar conductivity, (infrared and Raman) spectroscopy, thermal analyses (TGA/DSC), UV-vis spectra, and ESR for copper(II) decxycholate complex investigations were performed in the structural assignments of Co(II), Ni(II) and Cu(II) decxycholate complexes. Reaction of the sodium deoxycholate ligand (C24H39O4Na) with three transition metal ions form the complexes of formulae, [M(C24H39O4)2(H2O)2] . xH2O where M = Co(II), Ni(II) and Cu(II) where x = 2 for Cu(II) and x = 4 in case of M = Co(II) or Ni(II) metal ions. The FTIR spectra of the complexes show that decxycholate molecule is present as bidentate ligand. Molecular docking utilizing to additionally examine the interaction of COVID-19 (6LU7) with different complexes of deoxycholic acid with Co(II), Ni(II) and Cu(II). Furthermore, in the case of Co(II) deoxycholate complex, the probe is surrounded by amino residues Met235, Pro241, Glu240, Pro108, Gln110, Phe294, and Ile152. The probe molecule of Ni(II) deoxycholate complex is sited close to amino acids Tyr126, Tyr239, Leu287, Leu272, and Lys137. For, Cu(II) deoxycholate complex, the residues of amino acids comprise of Pro132, Pro108, Gln110, Gly109, Ile200, Asn203, Val202, His246, Pro293 and Tyr154. The binding energy was determined from the docking reads for Co(II)–6LU7, Ni(II)–6LU7 and Cu(II)–6LU7 deoxycholate compounds were found to be −446.99, −500.52, −398.13 kcal mol−1 individually

In situ thermal decomposition route: Preparation and characterization of nano nickel, cobalt, and copper oxides using an aromatic amine complexes as a low-cost simple precursor

The main interest now is the development of metallic or inorganic-organic compounds to prepare nanoparticle materials. The use of new compounds could be beneficial and open a new method for preparing nanomaterials to control the size, shape, and size of the nanocrystals. In this article, the thermal decomposition of [M2(o-tol)2(H2O)8]Cl4 (where o-tol is ortho-tolidine compound, M = Ni2+, Co2+, Cu2+) new precursor complex was discussed in solid-state conditions. The thermal decomposition route showed that the synthesized three complexes were easily decomposed into NiO, Co3O4 and CuO nanoparticles. This decomposition was performed at low temperatures (~600°C) in atmospheric air without using any expensive and toxic solvent or complicated equipment. The obtained product was identified by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). FT-IR, XRD and EDX analyses revealed that the NiO nanoparticles exhibit a face-centered-cubic lattice structure with a crystallite size of 9–12 nm. The formation of a highly pure spinel-type Co3O4 phase with cubic structure showed that the Co3O4 nanoparticles have a sphere-like morphology with an average size of 8–10 nm. The XRD patterns of the CuO confirmed that the monoclinic phase with the average diameter of the spherical nanoparticles was approximately 9–15 nm