Distribution Of Fe3O4 Nanoparticles Research Articles

Investigating The Effect of Magnetite (Fe3O4) Nanoparticles on Mechanical Properties of Epoxy Resin

In this paper, study the effects of magnetite nanomaterial Fe3O4 on the mechanical properties of epoxy. Dispersion of Fe3O4 nanoparticles in the epoxy resin was performed by ultrasonication. The samples of the nanocomposites were prepared using the casting method. The nanocomposites contain epoxy resins as a matrix material incorporated by different weight percentages of magnetite Fe3O4 that varies from 0wt.% to 15wt.% as a reinforcing material. The epoxy with the additive reinforcement materials Fe3O4 was slowly mixed in a sonication bath for 15 minutes, then the mixture poured into silicon molds. Field Emission Scanning Electron Microscopy FESEM and X-ray diffraction spectra XRD were used to characterize the morphological and structural properties of preparing samples and the distribution of Fe3O4 nanoparticles to the epoxy resin. Mechanical testing consists of tensile, hardness shore, and three-point flexural tests were performed on the samples at room temperature according to ASTM standards. The results showed that reinforcement by 15wt.% of Fe3O4 nanoparticles maximizes these mechanical properties of nanocomposites compared with pure epoxy except for the young modulus's preferred weight at 9 wt.%, this is due to aggregation of the additives nanomaterials in epoxy resin above 9 wt.%.

Preparation and properties of magnetic polymer microspheres

Magnetic particles are widely used in medical diagnosis and treatment owing to their ever-increasing magnetic targeting ability and superparamagnetism. However, small particle size and low magnetic saturation (MS) are disadvantageous for targeted delivery of magnetic particles. In this study, Fe3O4@polyvinyl alcohol (PVA) microspheres were prepared by an on-chip droplet microfluidic technology on a polydimethylsiloxane microchip. The morphology and elemental analysis test results demonstrate that Fe3O4@PVA microspheres have a uniform particle size and even distribution of Fe3O4 nanoparticles on microspheres. The MS reaches 15.43 emu·g−1 when the concentration of Fe3O4 is 33.3%, which linearly increases with an increase in the content of Fe3O4 in the microspheres. The microscopic observation results of magnetic motion further prove that Fe3O4@PVA microspheres maintain good superparamagnetism and drivability. This preparation process is simple, fast, and accurate. Fe3O4@PVA microspheres show many potential applications in medical diagnosis and treatment.

Structure and magnetic properties of PP+Fe3O4 nanocomposites depending on manufacturing techniques

The structures and magnetic properties of the PP[Formula: see text]+[Formula: see text]Fe3O4 nanocomposites manufactured by different technological techniques were studied in this work. Polymeric nanocomposite materials based on PP[Formula: see text]+[Formula: see text]Fe3O4 were obtained by two technological methods: hot pressing and extrusion. Scanning electron microscopy (SEM) and AFM investigations of nanocomposites were carried out for structure analysis. It was found that the distribution of Fe3O4 nanoparticles in the polymer matrix for nanocomposites obtained by the hot pressing method is uniform and monodisperse. Compared to this, the heterogeneous and inhomogeneous distribution of nanoparticles in the polymer matrix for the samples that were produced through extrusion method was observed. Furthermore, the nanocomposite samples produced via the extraction method have a lower surface regularity rather than those obtained by hot pressing. M(H) and M(T) studies of polymer nanocomposite samples synthesized through both technological methods were performed. Studies have shown that for relatively low concentrated samples — PP[Formula: see text]+[Formula: see text]10% Fe3O4, the values of the saturation magnetization were close, but the magnetization of nanocomposites obtained by heat pressing was slightly higher than the other samples. This is because the samples obtained by hot pressing method are characterized by higher uniformity and structure that is called “flat packaging”.

Structure and electrophysical properties of polyvinylidene fluoride (PVDF)/magnetite nanocomposites

In the present study, the effect of magnetite (Fe3O4) nanoparticles on the structural and dielectric properties of poly(vinylidene fluoride) (PVDF) matrix was investigated. Distribution of Fe3O4 nanoparticles in the polymer matrix has been studied by scanning electron microscopy (JEOL JSM-7600 F). The structure of the nanocomposite samples was investigated by the X-ray diffraction and Fourier-transform infrared spectroscopy. It was shown that the dielectric permittivity of PVDF + Fe3O4 nanocomposite samples was gradually increased up to 7 wt% of Fe3O4 content. Further increase in the concentration of the filler leads to decrease in the dielectric permittivity. The subsequent decrease in dielectric permittivity at higher Fe3O4 content can be explained by the increase in defects in the structure of the nanocomposite. The comparison of experimental data and the results of theoretical calculations show that the reduction in the empirical value of dielectric permittivity of the nanocomposite is obviously linked with the threshold value of filler. While calculating the theoretical value of the dielectric permittivity for the higher content of the filler, defects in the nanocomposite structure should be considered.

Sodium ascorbate assisted uniform distribution of Fe3O4 nanoparticles on rGO surface: improved cycling and rate performance of rGO/Fe3O4 anode material for lithium ion batteries

Reduced graphite oxide (rGO)–magnetite (Fe3O4) composites, promising anode materials for lithium ion batteries, have aroused extensive interest. However, the effects of reducing agents of graphite oxide (GO) on the detailed morphology of the composite were rarely reported. Herein, reducing agents of GO, sodium ascorbate and hydrazine hydrate were selected, and sodium ascorbate was able to control the uniform distribution of Fe3O4 on rGO sheets, resulting in stable cycling performance of above 500 mA h g− 1 after 100 cycles and high capacity of above 1200 mA h g− 1 in the first discharge/charge process. While in the composite reduced by hydrazine hydrate, severe aggregation of Fe3O4 particles and their weak bonding to rGO sheets depleted the buffer effect of rGO, resulting in continuously fading of cycling performance. This work provided a convenient and an effective way of morphology control of rGO–Fe3O4 composite during its one-pot formation.

Study on Electromagnetic Properties of Fe3O4 Nanoparticles Dispersed in Cellulose Matrix with Core-Shell Structure

Fe3O4/cellulose composite, a novel microwave absorption material, was successfully synthesized by the surface-initiated free-radical polymerization. The broad absorption peak at ∼3000 cm−1 indicated that the Fe3O4 polymerized with nanoscale cellulose through hydrogen bonding and electrostatic interactions. Synthesized composite consists of two phases, matrix (cellulose) and substrate (Fe3O4) with a uniform distribution of Fe3O4 nanoparticles in the matrix from SEM micrographs. Compared to other inorganic–organic composites, the composite showed a lowest density of 1.48 g/cm3, fulfilling the requirements of an excellent electromagnetic (EM)-wave absorbing material. The permeability and permittivity of the composite using 5 wt% initiator varied remarkably at ∼17 GHz, and the reflection loss value reached –13 dB at 17 GHz. The partial demagnetization caused by the uniform dispersion of Fe3O4 nanoparticles enhanced the magnetic anisotropy of the composite, thus increasing the EM-wave absorption characteristics. The excellent physiochemical and microwave absorption properties could promote the development of EM-wave absorbing material consisting of inorganic–organic composites.

Influence of the synthesis conditions on the size of Fe3O4 nanoparticles obtained by the sonochemical method

The influence of the synthesis conditions (duration and accepted acoustic power, concentration of the precipitator and initial reagents) on the size and size distribution of Fe3O4 nanoparticles was determined. The optimum ultrasonication time with a frequency of 35 kHz and an accepted acoustic power of 3.7 W for the synthesis of the nanoparticles with the narrowest size distribution is 5 min. The synthesized nanoparticles were characterized by scanning electron microscopy and X-ray diffraction analysis.

Investigation of nanostructured Fe3O4 polypyrrole core-shell composites by X-ray absorbtion spectroscopy and X-ray diffraction using synchrotron radiation

In this article, we focus on the structural peculiarities of nanosized Fe3O4 in the core-shell nanocomposites obtained by polymerization of conducting polypyrrole shell around Fe3O4 nanoparticles. The local structure of Fe atoms was determined from the Extended X-ray Absorption Fine Structure analysis using our own package computer programs. An X-ray diffraction method that is capable to determine average particle size, microstrains, as the particle size distribution of Fe3O4 nanoparticles is presented. The method is based on the Fourier analysis of a single X-ray diffraction profile using a new fitting method based on the generalized Fermi function facilities. The crystallites size obtained by X-ray diffraction spectra analysis was estimated between 3.2 and 10.3 nm. Significant changes in the first and the second Fe coordination shell in comparison with standard bulk were observed. The global and local structure of the nanosized Fe3O4 are correlated with the synthesis conditions of the core-shell polypyrrole nanocomposites.

Handling the particle size and distribution of Fe3O4 nanoparticles through ball milling

Handling the particle size and distribution of Fe3O4 nanoparticles through ball milling