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Synthesis of magnetite (Fe3O4) nanoparticles (NPs) with high purity, stability, and small sizes for biomedical applications is in high demand. The research on Fe3O4 NPs has been rapidly expanding and holds considerable promise for advancing new technologies and enhancing existing ones. Herein, Fe3O4 was synthesized from iron ferrous chloride (II) and sodium hydroxide (NaOH) on air, and then coated with gum Arabic (GA) in a single step. The characterizations were investigated using UV–Vis absorption, ultra-high-resolution scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). Compared to bare Fe3O4, GA-coated magnetite nanoparticles (GA-Fe3O4) showed a uniform cubic morphology with a mean size of 8.61 ± 1.31 nm. Stability studies were performed via dynamic light scattering (DLS) technique, zeta (ζ) potential, and observing the precipitation of NPs over 5 weeks. GA-Fe3O4 showed higher stability of -34.5 mV compared to -23.1 mV for bare Fe3O4. Further, GA-Fe3O4 NPs demonstrate interesting magnetic properties that can be efficiently separated from the reaction medium with the aid of an external magnet. The magnetic properties of GA-Fe3O4 were confirmed through VSM analysis, revealing a significantly high saturation magnetism of approximately 226 emu/g. GA-Fe3O4 NPs are promising magnetic NPS that can offer several benefits in biomedical applications, such as increased biocompatibility, improved stability, and enhanced functionality. [ABSTRACT FROM AUTHOR]

Pure and tin-doped magnetite nanoparticles (NPs) were synthesized successfully by co-precipitate method. Scanning electron microscope (SEM) and energy-dispersive X-rays (EDX) specified quantitative evidence for synthesized NPs. The pure and tin-doped magnetite NPs have average particle size of 30 nm and 200 nm, respectively. The magnetite NPs indicate well-defined magnetic behavior and doping of non-magnetic tin decrease its magnetization. The EDX graph indicated doping of Sn+2 ions, whereas XRD results were very effective in structural analysis. The rietveld refinement was helpful for determination of material's structure. The doping of tin in magnetite structure was also specified by FTIR peak at ∼ 546 cm - 1 . The pure and tin-doped magnetite NPs showed almost same antimicrobial behavior against Staphylococcus aureus, whereas tin-doped magnetite NPs showed more antimicrobial behavior against Escherichia coli. These NPs are biocompatible and show effective antimicrobial behavior; therefore, these NPs are potent candidates for biomedical application. These NPs also showed incredible adulticidal behavior against Aedes aegypti, which have been characterized for the first time in the literature. [ABSTRACT FROM AUTHOR]

Nickel matrix was electrodeposited on a conducting substrate from nickel Watts's bath having priorly dispersed graphene nanoplatelets (GNPs) to produce GNPs-Ni composite coatings. It was found, by atomic force microscopy, that addition of GNPs improved the hardness as well as the roughness of the coatings in proportion to the GNPs addition. While observing the torn surfaces under scanning electron microscope, pure nickel coatings showed a pure ductile behavior but as the volume of GNPs is increased, the torn surfaces showed nearly brittle behavior as for the 0.4 wt.% GNPs composites. The electrochemical and thermo-mechanical analysis showed 0.2 wt.% GNPs' addition as optimum concentration with highest corrosion resistance and strain recovery in comparison to other compositions. The corrosion rate of nickel matrix was best inhibited by 0.2 wt.% GNPs addition due to the uniform dispersion and dense structure overall. The thermomechanical analysis at 473 K temperature showed highest strain recovery rate for the 0.2 wt.% GNPs composites due to homogeneous dispersion. [ABSTRACT FROM AUTHOR]

Zinc Ferrite Nanoparticles were synthesized using the eco-friendly green synthesis protocol. Gongronema Latifolium (GL) leaf extract as a potential reducing and capping agent to influence the properties of ZFNPs for effective hyperthermia application is emplaced in this work. Characterizations techniques such as X-rays diffractometer (XRD), scanning electron microscope (SEM), Fourier transforms infrared (FTIR) spectroscopy, UV–visible spectroscopy and vibrating sample magnetometer were used to determine the properties of the samples. The SEM showed spherical morphology of the samples, XRD spectra revealed the crystallinity with a maximum crystallite size of 30.6 nm, the absorbance surface plasmon resonance peak from the UV result falls within the visible range. The FTIR result showed the various functional group responsible for the reduction of the sample. The VSM confirmed the superparamagnetic nature of the sample. The saturation magnetization increases as the concentration of GL increases. The hyperthermia application properties investigated revealed good specific loss power, which decreases from 207.8 to 105.3 W/g as the concentration of GL increases. Notably, the synthesized nanoparticles have the potential for hyperthermia application in cancer therapy. [ABSTRACT FROM AUTHOR]

Ce-doped α-Fe2O3 nanoparticles were successfully synthesized by hydrothermal method at different pH. The relationship between the pH of the solution and the morphology, structure and electrochemical stability of the prepared Ce-doped α-Fe2O3 nanoparticles was investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscope, Fourier transform infrared, X-ray photoelectron spectroscopy, electrochemical methods and saltwater immersion experiment. The results showed that the Ce-doped α-Fe2O3 nanoparticles prepared at pH = 4 and pH = 6 had surface defects structure, and the Ce-doped α-Fe2O3 nanoparticles prepared at pH = 8 had adhesion structures, which were CeO2 nanoparticles adhered to the α-Fe2O3 nanoparticles' surface. The fact that Ce ions could be readily doped into the α-Fe2O3 lattice, causing lattice distortion and increasing the binding energy of Fe3+ in the lattice, thereby enhancing the stability of Fe–O bonds correspondingly. At the same time, the surface defect structure is produced, which has the effect of promoting the compactness of the coating. The surface defects structure of α-Fe2O3 has stronger electrochemical stability than the adhesion structure of α-Fe2O3 and Bayer α-Fe2O3. It was found that waterborne acrylic coatings prepared from of α-Fe2O3 with surface defects structure had a stronger hindering effect on the diffusion of charged ions. [ABSTRACT FROM AUTHOR]

The present work reports a simple approach for large-scale synthesis of hausmannite manganese oxide, Mn3O4 nanoparticles. The as-synthesized nanoparticles were subjected to different characterization techniques such as X-ray diffraction, FT-Raman, Fourier transform infrared spectroscopy, scanning electron microscope with energy-dispersive X-ray spectroscopy, transmission electron microscope and vibrating sample magnetometer analysis. The electrical properties are examined with current–voltage characteristics. Crystal phase and hausmannite structure were confirmed by X-ray diffraction and Raman analysis. The resulting nanoparticles exhibited uniform size distribution and good stability as confirmed from electron microscopy studies. The synthesized nano-Mn3O4 is further evaluated for its potential in dye degradation and photocatalytic applications. The coexistence of Mn3O4 and H2O2 plays an important role on efficient decomposition of methylene blue dye from water. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide MoS2 nanoparticles have been synthesized by an inexpensive slow evaporation method. The X-ray diffractogram (XRD) showed that the grown particles are in crystalline nature with mixed phase. The calculated average particle size of the prepared nanoparticles is 56 nm. The Fourier transform infra-red (FTIR) and Raman studies confirm the particles are bulk MoS2 in nature. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) images confirm the porosity and the presence of Mo and S elements. Photocatalytic activity of the prepared nanoparticles is tested against methylene blue (MB), and malachite green (MG) dyes and the efficiencies are found to be 93.68% and 85.33%, respectively. The degradation rate constant of MoS2 nanoparticles against MB and MG dyes are 0.0199, 0.01389 min−1, respectively, under visible light for 75 min irradiation. A density functional theory calculation has been performed to validate the photocatalytic experimental results based on bandgap, band edge potentials, and effective mass. The DFT results are related to the experimental values, and the discussions are presented. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanowires have attracted great interest in nanodevices. In this work, the tribological characteristics of vertically grown ZnO nanowires obtained by metalorganic chemical vapor deposition were investigated by using an atomic force microscope (AFM). The ZnO nanowires were slid against flattened silicon and diamond-coated AFM probes under 50–150 nN normal force while monitoring the frictional force. The wear of the ZnO nanowires was observed by a scanning electron microscope and quantified based on Archard’s wear law. Also, the wear debris accumulated on the silicon probe was analyzed by using a transmission electron microscope (TEM). The results showed that the wear of ZnO nanowires slid against the silicon probe was extremely small. However, when the ZnO nanowires were slid against the diamond-coated probe, the wear coefficients ranged from 0.006 to 0.162, which correspond to the range of severe wear at the macroscale. It was also shown that the friction coefficient decreased from 0.30 to 0.25 as the sliding cycles increased. From TEM observation, it was found that the ZnO wear debris was mainly amorphous in structure. Also, crystalline ZnO nanoparticles were observed among the wear debris. [ABSTRACT FROM AUTHOR]

This manuscript aims to investigate the structural, thermal, and dielectric properties of polyester/Ni0.5Zn0.5Fe2O4 nanocomposites. The synthesized samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscope, transmission electron microscope (TEM), thermogravimetric analysis (TGA), and dielectric measurements. The XRD patterns confirmed the existence of both polyester and Ni0.5Zn0.5Fe2O4 nanoparticles peaks. FTIR analysis confirmed the incorporation of Ni0.5Zn0.5Fe2O4 nanoparticles into the polyester matrix in agreement with XRD results. SEM micrographs showed distribution of nanoparticles inside the polymer and TEM image showed a little agglomeration of Ni0.5Zn0.5Fe2O4 with flake-like micrometer-sized particles. The incorporation of nanofiller into the polymer increases the thermal stability as the weight losses reduced with nanoparticles content. Dielectric analysis depicted the enhancement in both real and imaginary parts of permittivity when nanoparticles concentration increased. Additionally, the AC conductivity increased while the electric impedance decreased with increasing Ni0.5Zn0.5Fe2O4 concentration. [ABSTRACT FROM AUTHOR]

Since the advent of material science, nanomaterials have been the most attractive and alluring research domain of nanotechnology with a variety of applications. Considering the significance of nanomaterials specifically in industrial progressions, the present work demonstrates facile synthesis approach of copper–zinc ferrite nanoparticles and their thermo-physical characterization and evaluation. Analytical grade chemicals were used to synthesize the respective nanoparticles employing the co-precipitation method, with the base solution of NaOH to maintain pH of the solution within range of 12–14. A series of nanoparticles were synthesized varying the amount of copper and zinc precursors, and their thermal and physical properties were evaluated using various analytical tools including XRD (X-ray diffraction), SEM (Scanning Electron Microscope), FTIR (Fourier transform infrared spectroscopy) and thermal constant analyzer. [ABSTRACT FROM AUTHOR]

Abstract: A rapid combustion process for the preparation of magnetic NixCu(1−x)Fe2O4 (x = 0.1-0.9) nanoparticles was introduced. Magnetic NixCu(1−x)Fe2O4 nanoparticles were characterized by XRD, SEM, TEM, SAED, and VSM. The results showed that x value, the volume of absolute alcohol and the calcination temperature were the three key factors to the size and properties of NixCu(1−x)Fe2O4 nanoparticles. Ni0.5Cu0.5Fe2O4 nanoparticles calcined at 400 °C for 2 h with absolute alcohol of 25 mL were employed to research their adsorption characteristics of methyl blue (MB). The results indicated that the adsorption kinetics of MB onto Ni0.5Cu0.5Fe2O4 nanoparticles could match the pseudo-second-order kinetics model very well, while the adsorption isotherm could be described by Langmuir model. It revealed that the adsorption of MB onto Ni0.5Cu0.5Fe2O4 nanoparticles was monolayer adsorption mechanism. Besides, the effect of pH on adsorption was investigated, and the maximum adsorption capacity was up to 78.3 mg/g when the pH value of solution was 5.Graphical abstract: Magnetic NixCu(1−x)Fe2O4 nanoparticles were prepared via a rapid combustion process, and were characterized by XRD, SEM, TEM, SAED, and VSM. The three key factors of x value, the volume of absolute alcohol, and the calcination temperature for the preparation of NixCu(1−x)Fe2O4 nanoparticles were investigated. Ni0.5Cu0.5Fe2O4 nanoparticles were employed to research their adsorption characteristics of methyl blue (MB), and the adsorption kinetics, the adsorption isotherm, and the adsorption mechanism were analyzed. [ABSTRACT FROM AUTHOR]

A simple method, which was based on self-assemble of silica nanoparticles and heptadecafluorodecyl trimethoxysilane, was used to fabricate a transparent superhydrophobic thin film with a water contact angle higher than 146°. The film has a uniform thickness of about 200 nm and a certain surface roughness about 20 nm, which makes it both transparent and superhydrophobic. [ABSTRACT FROM AUTHOR]