Journal of Sol-Gel Science and Technology最新文献

Based on industrial waste recycling, calcium silicate hydrate (CSH) powder was hydrothermally synthesized using carbide slag and silica fume from processes of hydrated acetylene and ferrosilicon alloy smelting with the mass ratio of 1:1. To address practical limitations of CSH powder as an adsorbent (e.g., particle loss, partial blocking and difficult separation), sodium alginate (SA) was introduced to fabricate SA/CSH composite gel beads and realize CSH immobilization. It was concluded that such gel entrapment did not impair Cu²⁺ and Ni²⁺ removal performance of CSH powder. When the mass ratio of CSH to SA was 0.5, Cu²⁺ and Ni²⁺ maximum adsorption capacities were up to 208.5 mg/g and 147.0 mg/g, respectively, with an initial concentration of 300 mg/L at 313 K under pH 6, in line with the fitting of the Langmuir isothermal model. And the kinetics were well fitted by the Ho quasi-second-order model. The coexisting Na⁺, Mg²⁺, and Ca²⁺ gradually weakened Cu²⁺ and Ni²⁺ adsorption with the increase in ion concentration. A large amount of Ca²⁺ active sites in SA/CSH gel promoted the chemisorption of Cu²⁺ and Ni²⁺ through ion exchange. In addition, functional groups such as COO-, -O-, and -OH in gel beads fully exerted synergistic complexation. A combined mode for SA/CSH regeneration using 0.02 mol/L EDTA-2Na elution coupled with 5 wt % CaCl₂ for Ca²⁺ replenishment achieved more than 85% of recovery rate after three cycles. Such SA/CSH gel thus presents a promising alternative for heavy metal removal from wastewater.

This work added to the increasing efforts to explore innovative materials for the future of photovoltaics, which was important given the solar industry’s pressing need for new and efficient materials. In this study, we revealed the promising optical and photovoltaic capabilities of mono phase lattice of barium ferrite by successfully incorporating Mn²⁺ ions for the first time to the best of our extent. Magnetic Ba_1-xMn_xFe₂O₄ (x = 0.0, 0.2, 0.3, 0.5) nanoparticles have been prepared by sol-gel auto combustion method. BaFe₂O₄ has received a little attention for its photovoltaic potential thus far, with much of its research focused on magnetic, radar absorption, and EMI (electromagnetic interference) shielding applications. Mn at varying substitutional concentration (20–50%) molar fraction was investigated to eliminate the disparity between magnetism and energy conversion encouraged by untapped potential of Mn incorporated ferrite nanoparticles as an innovative photo active material. X-ray diffraction demonstrated a structural transition from orthorhombic Pnma to Pmcn in pure barium ferrite to 20% Mn content, followed by orthorhombic Bb2₁m with 30% and 50% samples resulting in the reduction of crystallite size (43–39 ± 2 nm) with substitution. SEM and EDS settled the formation of sphere-shaped nanoparticles (229–61 ± 5 nm) and supported the presence of Mn with proposed scheme in all samples, respectively. With an increase in Mn concentration, VSM showed a notable improvement (M_s = 1.5–25 emu/g) in magnetism. The structural transition also correlated with increased light absorption and a narrowing of the optical band gap (1.5–2.0 ± 0.02 eV) revealed by DRS. The greenish-yellow portion of the CIE chromaticity diagram corresponded to the 573–576 nm range where visible emission was observed in PL spectra indicating defect levels and effective radiative recombination within the band structure refining charge carrier dynamics. The ferroelectric behavior reflected high leakage current for higher infused Mn samples by multiferroic system. Significantly, Mn-substituted samples showed elevated photo current density in current-voltage (I-V) directing their possibility as multipurpose material. Such optical behavior suggested the material’s potential to effectively absorb visible light and conversion. These results collectively strengthened that Mn infusion competently tailored the structural, magnetic, and optoelectronic characteristics of barium ferrite nanoparticles, hence enabling this combination as an efficient material for PV applications.

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Nitrate contamination poses a severe environmental threat due to its detrimental impact on aquatic ecosystems and human health, necessitating efficient remediation strategies. This study explores the potential of silver-doped titanium dioxide (Ag-TiO₂) nanoparticles as an advanced photocatalyst for nitrate removal from wastewater. Ag doping enhances the photocatalytic activity of TiO₂ by narrowing its bandgap energy and improving charge carrier separation, thereby facilitating efficient nitrate reduction under ultraviolet A (UVA) irradiation. The crystalline structure, morphology, oxidation states, and optical properties of the synthesized Ag-TiO₂ nanoparticles were characterized using various analytical techniques. A series of controlled batch experiments was conducted to investigate the effects of photocatalyst dosage (0.1, 0.5, 1.0, and 2.0 g) and initial nitrate concentrations (10, 25, 50, 80, and 100 mg-N/L) on the photocatalytic reduction process. The results indicate that 1.0% Ag-TiO₂ exhibits superior nitrate removal efficiency (over 97% within 90 min) compared to undoped TiO₂, with predominant conversion to environmentally benign nitrogen gas (N₂) and minimal accumulation of undesired byproducts such as nitrite (NO₃⁻) and ammonium ions (NH₄⁺). The enhanced performance is attributed to the plasmonic effect of silver, which extends the light absorption range into the UVA spectrum and suppresses electron-hole recombination. This study highlights the environmental sustainability of Ag-TiO₂ as an efficient, photocatalytically active material for nitrate remediation, presenting a promising solution for wastewater treatment applications.

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In this report, we used a cost-effective, green, and sustainable synthesis method for zinc oxide (ZnO) nanoparticles (NPs) using Azadirachta indica leaf extract. XRD results confirmed the hexagonal crystalline phase (average crystallite sizes 20–30.5 nm), FTIR identified the main functional groups, SEM revealed rod-like morphology, and EDX confirmed the elemental purity. The UV-vis spectra exhibited a blue shift, indicating a reduction in particle size and an increase in the bandgap. The in vitro and in vivo anti-diabetic activities of the prepared ZnO-NPs demonstrate an increase in glucose adsorption and promote glucose uptake by yeast cells. In diabetic mice, NPs reduced blood glucose levels (274–140 mg/dL), comparable to those of the standard drug (278–134 mg/dL). The heat-induced hemolysis and human red blood cell (HRBC) membrane stabilization assays were used to study the anti-inflammatory activity, showing inhibition rates ranging from 9.2% to 64%, consistent with those of the standard drug (12–67%). Antibacterial activity against E. coli bacteria using the well diffusion method (WDM) exhibited inhibition zones of up to 19.6 mm, comparable to the standard drug’s 21.6 mm. The overall findings of the study highlight the biomedical potential of ZnO-NPs using Azadirachta indica leaf extract.

The production and characterization of MoS₂@({{Co}}_{3}{S}_{4}) nanocomposites have primary importance in the enhanced uses of electrolytic energy storage. The utilization of Camellia sinensis (green tea) extract as a natural, green reducing and stabilizing agent in a hydrothermal synthesis method is what makes this work novel. Packed with flavonoids and polyphenols, the extract reduces the need for dangerous chemicals while promoting the regulated nucleation and development of the MoS₂@({{Co}}_{3}{S}_{4}) composite. The successful creation of a crystalline MoS₂@({{Co}}_{3}{S}_{4}) heterostructure with a 25.7 nm crystallite size was verified by X-ray diffraction (XRD). The presence of distinctive Co–S and Mo–S bonds, as well as surface hydroxyl and organic functional groups, was further confirmed by FTIR analysis, suggesting successful integration and surface functionalization. The redox peaks were detected by cyclic voltammetry (CV), supporting pseudocapacitive behavior. Excellent electrochemical performance was shown by galvanostatic charge-discharge (GCD) experiments, which demonstrated an 865 F/g maximal specific capacitance at 0.8 A/g. Following cycling, electrochemical impedance spectroscopy (EIS) demonstrated enhanced ion transport and low charge transfer resistance. High dielectric constant and AC conductivity were found in the dielectric characterization, confirming its multifunctionality. The present MoS₂@Co₃S₄ material can be considered an advanced green-synthesized electrode material due to its high specific capacitance (865 F/g at 0.8 A/g), low charge-transfer resistance, and enhanced dielectric properties, which collectively represent a significant improvement over many reported MoS₂ and Co₃S₄-based materials.

Graphical Abstract

Synergistic electrochemical and structural properties of MoS₂@Co₃S₄ nanocomposite for high-performance energy storage.

Copper doped nickel-zinc ferrites nanoparticles with formula Cu_XNi_(0.5-X)Zn_0.5Fe₂O₄ where, X = 0.0, 0.1, 0.2, and 0.3 were successfully synthesized using a facile and rapid sol-gel technique at room temperature. X-ray diffraction studies were performed to assess the crystallinity and phase purity, revealing the formation of well-defined single phase spinel nanostructures. The variation in Cu concentration appeared to influence lattice properties and crystallite sizes, exhibiting as these ions were successfully incorporated into the spinel lattice. The change in grain size with evolving x values reveals that the Cu substitution levels play a pivotal role in the ferrite nanoparticles sintering and growth process. The electrical conduction mechanism in ferrites is predominantly attributed to electron migrating among Fe(II) and Fe(III) ions onto octahedral (B) sites of spinel nanostructures. This route is influenced by the proportions of divalent and trivalent iron ions, which are additionally affected by Cu substitution levels. The regular variation in copper content in nickel zinc ferrite has significant implications for the material’s structural, electrical, and magnetic characteristics. Structural changes, especially changes in the lattice constant and particle size, are accompanied by variations in electrical conductivity, which are modulated by the hopping process of mixed-valence iron ions. The magnetic characteristics are further impacted by magnetic interactions between cations onto both tetrahedral (A) and octahedral (B) sites, which are modified by varying the concentration of substituent ions. This work sheds light on how controlled doping may be used to alter the multifunctional attributes of ferrite nanoparticles for possible applications in magnetic, electrical, and catalytic sectors.

Spintronics, which merges principles of magnetism and electronics, has emerged as a transformative field with the potential to revolutionize data storage, logic devices, and quantum technologies. Metal oxide nanostructures synthesized via sol–gel techniques are particularly promising for spintronic applications due to their low-cost fabrication, tunable structures, and magnetic functionalities. This mini-review summarizes recent advances in sol–gel-derived magnetic metal oxides, including transition-metal-doped TiO₂, La_1−xSr_xMnO₃, Co-doped ZnO, and Fe₃O₄, focusing on their synthesis, structural control, and room-temperature ferromagnetism. The influence of the sol–gel process on dopant distribution, grain boundary effects, and defect-mediated magnetism is discussed in detail. Key spintronic properties such as magnetoresistance, spin polarization, and magnetodielectric behavior are highlighted, along with current challenges in reproducibility and phase purity. Finally, the review outlines future directions for integrating sol–gel-derived metal oxides into practical spintronic devices, aiming to connect sol–gel chemistry with condensed matter physics and provide guidance for researchers at the intersection of materials science and spintronics.

In this novel research, an effective S-scheme Bi₂O₂CO₃/TiO₂ heterostructure was constructed by coupling TiO₂ with various proportions of Bi₂O₂CO₃ for mitigating rhodamine B dye under commercial visible LED lamp. Mesoporous Bi₂O₂CO₃/TiO₂ heterojunction with 10 wt% Bi₂O₂CO₃ nanoparticles were generated via sonochemical method. Through the employment of DRS, XPS, SEM, PL, HRTEM, XRD, SEM, EDX and N₂-adsorption-desorption isotherm, the complete characterization of the specimens was evaluated. Photoluminescence analysis recorded that the transportation rate of electron-hole pairs of TiO₂ has been strongly promoted after being hybridized with Bi₂O₂CO₃ nanoparticles. The experimental results revealed that Bi₂O₂CO₃ recorded a crucial role in both photocatalytic activity and light harvesting of titania by depressing the optical band gap energy and elevated the surface parameters to more positive direction. The heterojunction with 10 wt% Bi₂O₂CO₃ improved and optimized the photocatalytic activity which destroyed 85.5% of RhB dye during 240 min of exposure to visible radiation with kinetic rate of 0.0082 min⁻¹.The pronounced improvement in the photocatalytic efficiency of Bi₂O₂CO₃/TiO₂ heterojunctions was attributed to the proper production of an auspicious S-scheme heterostructure with strong redox capability, employing reactive species OH^. and O₂^.- radicals in the photocatalytic reaction. PL spectrum of hydroxyterephthalic acid and reactive oxygen trapping experiments implied that S-scheme pathway was the appropriate model for elucidating the mechanism of the charge transfer mechanism between TiO₂ and Bi₂O₂CO₃ semiconductors.

The proliferation, differentiation or viability of cells on a bioactive surface such as ß-tricalcium phosphate (ß-TCP) is a key aspect of regenerative medicine and biomaterials research. In this study, a sol-gel solution specifically developed for biomaterial applications was used, into which crystalline ß-tricalcium phosphate (ß-TCP) powder was added at various concentrations. This approach differs from conventional methods where ß-TCP is synthesized directly within the sol–gel matrix. The direct incorporation of powder into the base sol allows for better control over particle distribution and size, influencing the morphology, mechanical properties, and biological activity of coatings applied to titanium substrates. The surfaces were characterized in terms of changes in roughness, wettability, and mechanical parameters. Biological tests with the MG63 cell line showed increased cell proliferation and adhesion, particularly during the first 48 h of cultivation, confirming the bioactive effect of the added ß-TCP powder. These results suggest the potential of this approach for developing bioactive coatings on titanium implants with improved osseointegration and stability.