Ecofriendly synthesis and characterization of Ni2+ codoped silica magnesium zirconium copper nanoceramics for wastewater treatment applications

Structural, optical, and electrochemical properties of tungsten-doped cadmium zinc phosphate nanoporous materials for energy storage and peroxide detection

The demand for clean, efficient, and sustainable energy storage solutions drives significant advancements in materials science. This study investigates the synthesis and characterization of cadmium zinc phosphates (CdO-ZnO-P2O5) doped with different tungsten (CZWP) concentrations using the sol-gel method. The structural, binding energy, morphological, Brunauer-Emmett-Teller (BET) analysis, thermal, optical, and electrochemical properties were thoroughly examined. X-ray diffraction (XRD) confirmed a crystalline structure with tunable properties influenced by tungsten doping. Scanning Electron Microscopy (SEM) revealed well-ordered nanoparticles exhibiting a homogeneous distribution that was enhanced by W doping. BET reveals a moderate specific surface area, mesoporous structure, and dual-porosity characteristics, offering insights into their potential applications in photocatalysis, energy storage, and gas sensing. The TGA results indicate that tungsten doping in cadmium zinc phosphate reduces the material's coordinated water content and increases the thermal stability of the material. Optical analyses demonstrated a shift in the bandgap and an increase in optical electronegativity, highlighting the material's potential in optoelectronics. Electrochemical characterization using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) identified an optimal doping level of 2.0% W for improved charge transfer and specific capacitance, confirming its suitability for supercapacitors. Furthermore, the 2.0% W-doped electrode exhibited outstanding performance in hydrogen peroxide (H2O2) sensing, achieving high sensitivity, a wide linear range, and low detection limits. These findings highlight CZWP nanostructures as promising candidates for energy storage and sensing applications.

CuO/rGO doped with silver nanoparticles for humidity sensing applications

Determination of the relative humidity in the surrounding environment is essential for numerous industrial and technological applications. In this work, we successfully prepared CuO-rGO doped with varied Ag concentrations (0-1.5 wt%). The XRD measurements demonstrated that the structures were successfully developed with an average crystallite size of 30-40 nm as reflected from the (111) plane, with a dominating cubic phase. The SEM morphological characteristics demonstrated that the cubic structure was Cu-based, whilst the sheet-like structure was attributable to 2D rGO. The cubic structure tended to lose its regular shape, while the size tended to be reduced as the Ag doping ratio increased. Elemental analysis was confirmed through EDX for CuO-rGO doped with 1.5 wt% Ag, reflecting 35, 13, 1.4, and 50.6 wt% of C, O, Ag, and Cu, respectively. Assessment of the antimicrobial assets of the nanostructures versus G+ve (Staphylococcus), and G-ve bacteria (Escherichia coli) presented the highest activity for CuO-rGO doped with 1 wt% Ag. The humidity sensing evaluations were revealed throughout a wide set of frequencies (50-10 kHz) and humidity levels (11-97% RH). The optimum frequency was optimized as 50 Hz. The acquired response and recovery times were 154, and 172 s, respectively, while the sensitivity was 2 × 106 Ω per RH for CuO-rGO doped with 1.0 wt% Ag. Remarkably, the recovery time for CuO-rGO doped with 1.5 wt% Ag was 17 s. The sensor demonstrate decent repeatability for four cycles between 11% and 75% RH at a testing frequency of 50 Hz. The results nominate this structure as an affordable, low-cost, and applicable humidity sensor valid for nanotechnological and materials science routes.

Plant extract-mediated biosynthesis of sulphur nanoparticles and their antibacterial and plant growth-promoting activity

This study reports green synthesis of sulphur nanoparticles using sodium thiosulfate pentahydrate (Na2S2O35H2O) and Cannabis sativa leaf extracts. X-ray diffraction (XRD) pattern and scanning electron microscopy (SEM) was employed to examine the crystallinity of the particles and morphological characteristics, proved both spherical and rod-shaped morphology of the S NPs having porous nature. The FTIR spectra revealed the interaction of the synthesized SNPs with the biomolecules present in the leaf extract. UV-VIS spectral investigations confirmed the production of SNPs from C. sativa leaf extract and that these SNPs can be used for visible region photocatalysis for the removal of pollutants from wastewater. Energy dispersive X-ray (EDX) spectrum of the SNP shows a single peak around 2.4 keV, confirmed S NPs purity. TEM image revealed the formation of mainly nanorods having a width of ∼20-25 nm and a length of 50-100 nm. Furthermore, some spherical particles (∼20-30 nm) were also formed. HRTEM image of the rod-shaped particles clearly shows the crystal fringe spacing of 0.38 nm. Further, disc diffusion method (DDM) was used to check the antibacterial activity of S NPs against gram-positive S. aureus (MTCC737) 18 ± 0.12 mm and gram-negative bacteria against E. coli (MTCC443) 21.5 ± 0.12 mm, A. salmonicida (MTCC1522) 19.1 ± 0.12 mm, K. pneumoniae (MTCC3384) 17.8 ± 0.10 mm. Among all the strains of bacteria, E. coli (MTCC443) showed a maximum zone of inhibition of 21.5 ± 0.12 mm and its antibacterial activity is somewhat like streptomycin sulfate. These SNPs also promote growth of C. sativa in pot experiment, resulting in a 30 % increase in biomass, 90 cm in shoot length and 28 cm in root length and higher fresh and dry weight (50g and 20g, respectively) with 1.0 mg mL-1 NPs treatment. In addition, SEM-EDX confirmed the accumulation of nanomaterial in plant leaves. This environmentally friendly approach to SNP synthesis using C. sativa extracts demonstrates both potent antibacterial properties and plant growth-promoting effects, making it a promising solution for agriculture and biomedicine.

Optimizing magnetic, dielectric, and antimicrobial performance in chitosan-PEG-Fe2O3@NiO nanomagnetic composites

There is a growing interest in eco-friendly and cost-effective organic-inorganic nanocomposites due to their alignment with the principles of "green" chemistry, as well as their biocompatibility and non-toxicity. This study focused on producing Chitosan-PEG-Fe2O3@NiO nanomagnetic composites to improve the stability, dielectric properties, and antimicrobial effectiveness of these nanocomposite materials. The process involved synthesizing Fe2O3@NiO via sol-gel and polymerizing chitosan-PEG. The nanocomposites were characterized by XRD, TEM, FTIR, optical, dielectric, and VSM. Incorporating Fe2O3@NiO significantly improved stability, and the interaction with Fe2O3 during the sol-gel process facilitated the formation of NiFe2O4 with an increase in the crystallinity within the chitosan-PEG matrix. The study examined optical and dielectric properties, highlighting that the 3 NiO-doped chitosan-PEG-Fe2O3 composites had high electrical conductivity (1.8 ∗ 10-3 S/cm) and a significant dielectric constant (106 at low frequencies). As the ratio of NiO NPs within the chitosan-PEG-Fe2O3 increases, the energy band gap of chitosan-PEG-Fe2O3 films decreases up to 3.7 eV. This decrease is owing to the quantum confinement effect. These composites also demonstrated improved antimicrobial activity against E. coli and S. aureus and higher activity in the presence of nanomagnetic particles. The minimum inhibitory concentrations of CS-PEG-Fe2O3/NiO NPs against (Bacillus cereus, M. luteus, S. aureus and (S. enterica, H. pylori, E. coli) were (22-35 mm) and (21-34 mm), respectively.

Construction and characterization of nano-oval BaTi0.7Fe0.3O3@NiFe2O4 nanocomposites as an effective platform for the determination of H2O2

Talented di-phase ferrite/ferroelectric BaTi₀.₇Fe₀.₃O₃@NiFe₂O₄ (BFT@NFO) in oval nano-morphology was chemically synthesized using controlled sol-gel processes and calcined at 600 °C. The effects of shielding using NiFe₂O₄ (NFO) nanoparticles on the microstructure, phase transition, thermal, and relative permittivity of BaTi₀.₇Fe₀.₃O₃ (BTF) nano-perovskite were systematically explored. X-ray diffraction patterns and Full-Prof software exhibited the forming of the BaTi₂Fe₄O₁₁ hexagonal phase. TEM and SEM images demonstrated that the coating of BaTi0.₇Fe₀.₃O₃ has been successfully controlled with exquisite nano-oval NiFe₂O₄ shapes. The NFO shielding can significantly promote the thermal stability and the relative permittivity of BFT@NFO pero-magnetic nanocomposites and lowers the Curie temperature. Thermogravimetric and optical analysis were used to test the thermal stability and estimate the effective optical parameters. Magnetic studies showed a decrease in saturation magnetization of NiFe₂O₄ NPs compared to their bulk system, which is attributed to surface spin disorder. Herein, characterization and the sensitive electrochemical sensor were constructed for the evaluation of peroxide oxidation detection using the chemically adjusted nano-ovals barium titanate-iron@nickel ferrite nanocomposites. Finally, The BFT@NFO exhibited excellent electrochemical properties which can be ascribed to this compound possessing two electrochemical active components and/or the nano-ovals structure of the particles which can further improve the electrochemistry through the possible oxidation states and the synergistic effect. The result advocates that when the BTF is shielded with NFO nanoparticles the thermal, dielectric, and electrochemical properties of nano-oval BaTi_0.7Fe_0.3O₃@NiFe₂O₄ nanocomposites can be synchronously developed. Thus, the production of ultrasensitive electrochemical nano-systems for the determination of hydrogen peroxide is of extensive significance.