Journal of Inorganic and Organometallic Polymers and Materials最新文献

The structural, optoelectronic, mechanical and thermoelectric features of Na₂PtX₆ (X = Cl and Br) for renewable energy applications are inspected by means of density functional theory DFT based calculations. Structural and thermodynamic stabilities are guaranteed by the Birch-Murnaghan equations of states, cohesive energy, and formation energy. The examined compounds are ductile, as indicated by the structural parameters and elastic constant analysis. For Na₂PtCl₆ and Na₂PtBr₆, the calculated direct band gaps of 3.20 eV and 2.24 eV ensure that light is absorbed in the visible and ultraviolet wavelength ranges. As a result, these materials are widely employed in solar cell and optoelectronic applications. The Boltztrap code is employed, which is based on the semi-classical Boltzmann transport equations (BTE), in order to investigate the thermoelectric properties. We have computed the electrical and thermal conductivities, Seebeck coefficient, power factor, and figure of merit (ZT) against temperature, carrier concentration, and chemical potential. According to the current study, Na₂PtX₆ (X = Cl and Br) is the most promising thermoelectric material for use in thermo power generation devices at a wide temperature range in the future.

In this study, we investigate the impact of diamagnetic Mg substitution on the crystal, magnetic and magnetocaloric effect (MCE) properties of the novel M-type Ba_0.5Ca_0.5Fe_12-xMg_xO₁₉ (x = 0.3, 0.4 and 0.5) BCFMO hexaferrites. The three series were synthetically prepared using the conventional solid-state process. X-ray diffraction (XRD) combined with Rietveld refinement, confirm the magnetoplumbite structure, alongside a secondary phase with space group R-3 m. The hexaplate-like grain sizes varied in the range of 2.37–1.9 µm, while the crystallite sizes are in the range of 119–104 nm. The FTIR spectra revealed two positions at 573 cm⁻¹ and 494 cm⁻¹ corresponding to the tetrahedral and octahedral sites, respectively, which confirmed the M-type hexagonal structure. The direct optical band gap energy (E_g) of BCFMO increases from 2.91 eV to 3.14 eV with varying Mg²⁺ concentration from 0.3 to 0.5. The presence of Fe in the + 3 oxidation state (Fe³⁺) and of Mg²⁺ is confirmed by XPS. The saturation magnetization M_s decreases from 111.18 to 72.34 emu/g which attributed to the addition of Mg²⁺ in Fe³⁺ in 12 k octahedral site and confirmed by DRX and XPS analyses. The increase of the coercivity H_C from 3.17 kOe to 5.81 kOe is due to the reduction in crystallite sizes. The anisotropy field H_a and the effective anisotropy constant K_eff rise from 12.13 to 21.78 kOe and 6.74 to 7.88 (10⁵emu/cm) for x = 0.3 to 0.5, respectively. The Para-Ferromagnetic phase transition at Curie Temperature T_C was identified for all compounds. The substitution by Mg²⁺ leads to a reduction of T_C from 730 to 693 K. The maximum entropy (− ΔS_m^max) decreases from 1.68 to 1.29 J/kg.K, while, the relative cooling power (RCP^max) increases from 110.58 J/kg to 217.9 J/kg for x = 0.3 to 0.5, respectively at µ₀H = 5 T. The results demonstrated that samples could be utilized for optoelectronic devices, permanent magnet, magnetic recording media and other magnetic applications.

Graphical Abstract

In this study, a novel hydrogel nanocomposite based on carboxymethyl cellulose (CMC) polysaccharide was fabricated by graft free radical co-polymerization of Itaconic acid and acrylamide monomers in the presence of Palygorskite clay. The nanocomposite, known as CMC-g-poly(AM-co-ITA)/Clay, was synthesized using potassium persulfate (KPS) as the initiator and N, N′-methylene bisacrylamide (MBA) as the cross-linker. The goal was to create nano adsorbents with excellent adsorption capacity, easy separation, selectivity, and superior reusability for eliminating dyes from aqueous solutions. The nanocomposite’s structure was analyzed using various techniques including FTIR, XRD, HRTEM, FESEM, TGA, and BET. The study of the nanocomposite’s thermal stability revealed that the one with 15% clay exhibited the best thermal stability. FESEM images showed a high cross-linking density and a porous surface, facilitating water diffusion and affecting the swelling behavior. The nanocomposites’ gel content and swelling behavior were compared with those of a hydrogel without clay when placed in water. The results indicated that as the clay content increased, the swelling ratio decreased while the gel content increased. The CMC-g-poly (AM-co-ITA)/Clay nanocomposite was found to have high stability in an aqueous solution and a negatively charged surface at a pH higher than 3.1. The findings indicated that adding clay to the hydrogel improved its ability to remove Brilliant Green from water. Introducing 15% clay into the hydrogel raised its maximum adsorption capacity for BG dye removal from 199.67 to 1513.55 mg/g. Various models were used to analyze the experimental results, with the pseudo-second-order demonstrating the best fit for the kinetic model. Equilibrium data were assessed using Langmuir, Freundlich, and Temkin isotherm models. The Freundlich model was found to best describe the uptake of BG dye, suggesting heterogeneous multilayer adsorption onto the nanocomposite. Thermodynamic parameters indicated that the adsorption of BG dye onto the nanocomposite was endothermic (ΔH > 0) and spontaneous (ΔG < 0). Additionally, the nanocomposite showed high reusability and easy separation, maintaining an 88.23% removal capacity for BG dye after 6 cycles.

A biopolymer matrix of chitosan (CTS) and algae (AGA) was chemically modified with a natural genipin (GEN) cross-linker agent via hydrothermal process. The resulting green adsorbent (CTS-GEN/AGA) was evaluated for removal of the cationic dye (methyl violet, MV) from aqueous media. The optimization of MV adsorption onto CTS-GEN/AGA was performed using the Box–Behnken design (BBD), considering the variables of adsorbent dose (0.02–0.1 g/100 mL), pH (4–10), and time (20–300 min). The CTS-GEN/AGA demonstrated the highest MV removal (76.49%) for optimal operational parameters: CTS-GEN/AGA dosage (0.0938 g/100 mL), pH (8.4), and contact time (215.3 min). The adsorption isotherm analysis revealed a close fit between the experimental data of MV adsorption and the Temkin model. Furthermore, the adsorption kinetics are well-described by the pseudo-second-order model. The maximum adsorption capacity of CTS-GEN/AGA was 71.9 mg/g at 25 °C. The probable adsorption mechanism can be assigned to H-bonding, electrostatic forces, and n–π stacking interactions. These findings highlight the potential of CTS-GEN/AGA as an effective adsorbent for treatment of wastewater for the removal of organic dyes.

The traditional inorganic flame-retardant magnesium hydroxide (MH) has since many years been dominating in flame-retardant applications. However, due to its poor compatibility with the epoxy resin matrix, it seriously affects the mechanical properties of the matrix. In the present study, MH has been organically modified to investigate the potential of a novel organic–inorganic hybrid as a flame-retardant curing agent (CEPPM-MH) for flame retardancy of epoxy resins. CEPPM-MH and ammonium polyphosphate (APP) were synergistically introduced into the epoxy thermosets to improve the fire resistance of the composites. For the S7 composite samples that contained 10% of APP and 10% of CEPPM-MH, the LOI was increased to 30.1. Also, the UL-94 test rating was increased to V-0, and the peak heat release rate (pHRR), total heat release (THR), total smoke production (TSP), and peak CO production rate(pCOPR)were reduced by 86%, 53%, 69%, and 79%, respectively, as compared with the pure sample S1. In addition, the flexural strength and flexural modulus were found to be improved by 76.8% and 45.1%, respectively, in the flexural performance test. Furthermore, the organic–inorganic hybrid curing agent, which was prepared by modifying the magnesium hydroxide with water as the only solvent, could be introduced into epoxy resins as both curing agent and flame retardant, which not only effectively reduced the fire risk but also improved the comprehensive performance of the materials. This provides a new idea for the preparation of intrinsically flame-retardant epoxy resins.

This paper explores the various characteristics of the Li₂Zr₆MnCl₁₅ chloroperovskites, including their structural, electronic, magnetic, optical, phononic, and thermoelectric properties. The computed phonon dispersions and formation energies provide strong evidence for the stability of this compound. Based on the analysis of magneto-electronic properties, it is observed that Li₂Zr₆MnCl₁₅ demonstrates a semiconductor (2.2 eV Up/0.55 Dn) behaviour with a magnetic moment of 4.00 µ_B. Comprehensive analysis of optical properties involved intricate calculations of various parameters related to the behaviour of light, such as dielectric constants, refractive indices, reflectivity, extinction coefficients, electron energy loss, absorption coefficients, and optical conductivity functions up to 14.0 eV. The research was carried out in the temperature range of 50 to 800 K to determine the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor (PF), Hall coefficient, and figure of merit for the investigated material, which showed great promise for use in thermoelectric devices, with PFs of about 7.5 × 10⁴ W/K²ms, respectively. Using the application known as phy-x: PDS, All of the gamma radiation shielding parameters of Li₂Zr₆MnCl₁₅ were determined, including mass attenuation coefficient (G_MAC), linear attenuation coefficient (G_LAC), half value (G_HVL), mean free path (G_MFP), the effective, effective atomic number (Z_eff), and effective electron density (N_eff). The research indicates that the G_MAC and G_LAC values for Li₂Zr₆MnCl₁₅ fall as the photon energy rises, with a noteworthy increase near K-edge absorption owing to the photoelectric effect dominance at low energy. Both Z_eff and N_eff declined as the photon energy increased, with Z_eff reducing from 25.56 to 25.27 and N_eff decreasing from 3.22 × 10²³ to 3.18 × 10²³ electrons/g. Due to their robust absorption patterns and high PF, these compounds show great promise as thermoelectric and optoelectronic materials.

Friction stir welding (FSW) is a new type of welding that is widely used in the automotive and manufacturing industries. The purpose of this work is to maximize the strength of dissimilar welded connections by examining how tensile strength is affected by tilt angle, axial force, welding speed, and rotating speed. The current study investigates the effect of rotational speed, welding speed, axial force, and tilt angle on the output response of tensile strength; these parameters were also studied with the use of a surface plot and a contour plot. The AA5052 and AA2219 alloys are chosen as the workpiece material due to their usefulness in a variety of settings. Materials are sized and shaped in accordance with the criteria of ASTM standard. Each output response is then assessed across all welding conditions when the tests are completed. The Taguchi L9 orthogonal array (OA) will be used to guide the planning of the experimental design. Taguchi based Grey relational analysis (GRA) was used to the experimenting data in order to optimize the multi-responses. Using the GRA method, numerous responses in an FSW approach may be optimized simultaneously. During GRA optimization, S/N ratios, Grey relational coefficients (GRC), and Grey relational grades (GRG) are calculated, with the latter used to establish ranks. In most cases, this strategy works well for enhancing the various results produced by the FSW approach.

Catalyst for ammonium percholorate (AP) decomposition was limited to inert particles, with subsequent decrease in main decomposition temperature. Recently much attention has been directed to reactive catalyst particles with high decomposition enthalpy. Energetic metal-organic frameworks (EMOFs) could contribute to the decomposition enthalpy; with the exclusive evolution of catalyst nanoparticles. UiO-66-NH₂ is a three-dimensional metal-organic framework (MOF) composed of tetravalent metal ions Zr(IV) and ditopic 2-Amino Terephthalic acid linker (H₂ATPT). UiO-66-NH₂ is multi-functional MOF with exceptional surface area and thermal stability. UiO-66-NH₂ can expose superior combustion enthalpy of 18 KJ/g. This study reports on facile solvothermal synthesis of UiO-66-NH₂; that was integrated into ammonium percholorate (AP) matrix via anti-solvent technique. UiO-66-NH₂ boosted AP decomposition enthalpy by + 227.3%, with decrease in main decomposition temperature by 92.72 °C. Decomposition kinetics was investigated via isoconversional (model free) and model fitting. Kissinger, Kissinger–Akahira–Sunose (KAS), integral isoconversional method of Ozawa and Flyn and Wall (FWO). UiO-66-NH₂/AP demonstrated apparent activation energy of 75 KJ mol^− 1 compared with 176.1 KJ mol^− 1 for virgin AP. While virgin AP experienced complex decomposition models beginning with F3 to A2; UiO-66-NH₂/AP nanocomposite demonstrated A3 decomposition model. The developed UiO-66-NH₂ exposed a dual function as high energy dense material with superior catalytic effect due to the exclusive evolution c-ZrO₂ nanocatalyst on decomposition.

In the present study, the aqueous seed extract of an Origanum marjorana plant and the fruit rind extract of a Garcinia indica plant were used to prepare ZnO nanoparticles. The antimicrobial effects of the prepared nanoparticles on bacterial pathogens and their antiproliferative effects on the HCT 116 cancer cell line were evaluated, with a specific focus on colon cancer. The prepared ZnO nanoparticles were characterized via XRD, SEM, FTIR, and UV‒Vis spectroscopy. The antibacterial activities of the synthesized nanoparticles were studied against both the gram-positive and gram-negative microorganisms B. cereus and S. typhi. These compounds presented moderate activity compared with the standard ciprofloxacin. The MICs for OM-ZnO were 2 µg/mL for S. typhi and 2 µg/mL for B. cereus. For GI-ZnO, 4 µg/mL for S. typhi and 4 µg/mL for B. cereus were observed. These results confirmed that the antibacterial efficacy of the nanoparticles depends on their concentration. The antiproliferative effects of the ZnO nanoparticles were evaluated using the MTT assay and cell cycle analysis. ZnO nanoparticles showed good antiproliferative effects on the tested cell lines. Studies on the cell cycle have suggested that ZnO nanoparticles effectively induce cell cycle arrest at the G2/M phase and trigger apoptosis. Compared with untreated HCT 116 cells (9.31%), those treated with 80 and 160 µg/mL ZnO nanoparticles arrested 25.92% and 33.57%, respectively, at the G2/M phase of the cell cycle. This study effectively demonstrates the synthesis of ZnO nanoparticles using plant extracts, highlighting their antimicrobial and antiproliferative properties. The detailed characterization underscores their potential for applications in antimicrobial therapies and cancer treatment.

Conventional antifungal therapies becoming less effective in treating dermatophytic infections. For this reason, researchers are looking for alternative treatments. The current research has tested the antifungal efficacy of eight novel synthesized metallic nanoparticle compounds: Ag_0.49Cr_2.51O₄, Ag_0.99Fe_1.01O₃, CoLa_0.019Fe_1.981O₄, Co_0.99Fe_1.99O₄, Ag_0.99Cr_1.01O₂, Ca_0.99Fe_1.99O₄, CoBi_0.019Fe_1.981O₄, and Cu_0.99Fe_1.99O₄ were synthesized by a flash auto-combustion reaction to evaluate synergistic potential of the Np’s exhibited antifungal activity in combination with Cinnamon, clove, lemongrass, tea tree and thyme essential oils extracted by soxhlet method against Microsporum canis, Trichophyton tonsurans, T. violaceum, T. verrucosum, and Epidermophyton floccosum. Four nanoparticle compounds exhibited antifungal activity which were: Ag_0.49Cr_2.51O₄, Ag_0.99Fe_1.01O₃, CoLa_0.019Fe_1.981O₄, and Co_0.99Fe_1.99O₄ against all tested dermatophytes. Maximum inhibition was recorded in the cases of Ag_0.99Fe_1.01O₃, Ag_0.99Fe_1.01O₃ + cinnamon against M.canis. Least minimum inhibitory concentrations were attained by Cinnamon against M. canis, Ag_0.99Fe_1.01O₃ against M.canis, T. tonsurans, and T.violaceum, Ag_0.99Fe_1.01O₃+Cinnamon against M. canis, T. violaceum and, T. verrucosum, Ag_0.99Fe_1.01O₃ + Clove, and Ag_0.99Fe_1.01O₃ + Lemongrass against M. canis. The study showed promising results regarding the synergistic antifungal efficacy of nanoparticle compounds combined with essential oils in the cases of Ag_0.99Fe_1.01O₃ with cinnamon, Ag_0.99Fe_1.01O₃ with clove and Ag_0.99Fe_1.01O₃ with lemon grass against all tested dermatophytes.