Fe3O4 Compound Research Articles

Dielectric and Magnetic Composites of Fe3O4@APNs for Superior Microwave Thermal Effect.

As for the deep tissue infections of chronic osteomyelitis, antibiotics are hard to deliver into the infected bone tissue, which makes it difficult to be cured completely in clinic. Microwave has strong penetration, and the medium can produce a good bactericidal effect through the microwave thermal effect (MTE). Here, a new microwave sensitizer (Fe3O4@APNs) was prepared and evaluated. Black phosphorus nanosheets modified with phytic acid dodecasodium (APNs) were fabricated by a liquid-phase exfoliation method that exhibited good water oxygen stability. A complex with Fe3O4 compound and APNs (Fe3O4@APNs) was formed by an ultrasonic mixing process, which showed excellent MTE (quickly increased to 53.5 °C in 5 min at 2.45 GHz, 10 W/cm2) via dielectric versus magnetic loss (reflect loss value of -5.94 dB at 2.45 GHz). The Fe3O4@APNs microwave sensitizer developed in this study has an outstanding in vitro antibacterial effect and might show promise for the treatment of chronic osteomyelitis enabled by local tissue heating via the MTE.

The carbon-doped Fe3O4 montmorillonite particle electrode for the degradation of antiviral drugs in electro-Fenton system

Since the outbreak of COVID-19, the extensive use of epidemic control drugs such as Arbidol (ARB) and Acyclovir (ACV) has significantly increased and the environmental pollution caused by these residues has attracted increasing attention. In this article, a novel montmorillonite graphene-like carbon hybrid Fe3O4 compound (Mt/GH/Fe3O4) as particle electrode catalyst was prepared and applied in three-dimensional-electro-Fenton (3D-EF) for the ARB and ACV degradation. The structure and composition of the compound catalyst were characterized. The degradation efficiency of targets was significantly increased in the 3D-EF degradation system and even more thorough for the degradation of targets, compared with simple 2D, 3D, and EF catalytic degradation systems. The degradation rate of antiviral drugs can reach >90% in 5 min with excellent stability. The research demonstrated that the clay mineral with a special structure loaded with graphene-like carbon and Fe3O4 had supplied an ideal reaction medium for the electro-Fenton reaction. Mt./GH/Fe3O4-based 3D-EF degradation system would have promising applications in the degradation and removal of antiviral drug residuals in the environment.

Production and characterization of magnetic textiles

In this study, 100% cotton fabrics were imparted with magnetic field properties using a conventional screen printing method to obtain magnetic fabrics in the context of smart textiles. The magnetism in the fabrics was generated by using a Fe3O4 compound. In order to make this compound adhere more strongly to the fabric sample, printing method was used as a finishing application. The Fe3O4 compound was added to the printing paste without using any dyestuff since the Fe3O4 compound had a unique color itself. The washing durability of the printed functional textiles were investigated. The washing fastness, acidic sweat fastness, alkaline sweat fastness, water fastness, dry rubbing fastness, wet rubbing fastness, tear strength, pilling and degree of external magnetic induction of the fabrics were analyzed. In addition, the morphological analyzes of the fabrics were performed by scanning electron microscopy (SEM-EDX) and X-ray crystallography (XRD) to determine the crystallographic properties of the materials and the phases they contained. According to the result of quantitative evaluation of magnetic fields on textile surfaces, Fe3O4 microparticles were in the range of 25 mT when they constituted 50% of the weight.Thus, it was found that a magnetic field was successfully generated in the textiles. Moreover, the magnetic property of the fabric was durable after the washing process as the mT values were maintained even after 20 washing cycles, and the fastness and performance tests were also at the highest level. Increasing the Fe3O4 content in the formulations used in the study improved the tensile strength by 2-7%. Comparing the test results of the fabric sample with the optimum formulation with the untreated fabric sample, it was also determined that the tensile strength increased by 8-10% on average after 20 washes.

Analysis of the protection performance of admixed citronella and myrrh essential oil extracts on high carbon steel corrosion in CH3COOH and C6H8O7 solution

Protection performance of admixed citronella and myrrh essential oil extract (CNM) on the corrosion resistance of high carbon steel (HCS) in 3 M of CH3COOH and C6H8O7 solution was evaluated by potentiodynamic polarization, open circuit potential measurement, weight loss measurement, x-ray diffractometry and ATF-FTIR spectroscopy. Results showed CNM performed effectively in CH3COOH with optimal inhibition of 87.47% and 80.12% at 1.67% concentration from potentiodynamic polarization and weight loss. CNM performed poorly in C6H8O7 solution with highest value of 41.29% and 43.81% at 1.67% CNM concentration from both tests. In both acids inhibition efficiency increased with increase in CNM concentration coupled with the exhibition of mixed-type inhibition effect. Open circuit potential plots show CNM significantly reduces the activation barrier for HCS to corrode wherewith the plots in the presence of CNM extract where significantly electropositive compared to the plot from C6H8O7 solution without CNM. In CH3COOH, the action of protonated CNM molecules and CH3CO2− anions results in the formation of complexes that increases the reactivity of HCS surface and its thermodynamic tendency to corrode despite effective inhibition performance. X-ray diffractometry shows admixed extract caused significant decrease in intensity/counts for diffraction peaks of Fe2O3 and Fe3O4 compounds on the spectrum plots compared to the plots without the extracts. ATF-FTIR spectroscopy shows significant reduction in transmittance at specific range of wavenumbers occurred within CNM/CH3COOH solution after corrosion, and on HCS surface after corrosion in the presence of the extracts compared to CNM/CH3COOH before corrosion. This contrast the results obtained from CNM/C6H8O7 solution.

Top-down and bottom-up approaches to obtain magnetic nanoparticle of Fe3O4 compound: Pulsed laser deposition and chemical route

Our goal in this work was to prepare nanoparticles (NPs) of Fe3O4 using two approaches: top-down and bottom-up. In the former two wavelengths (1064 and 532 nm) were used in the pulsed laser deposition (PLD) technique to produce NPs from α-Fe bulk, with subsequent heat treatment to produce Fe3O4, and in the latter the NPs were produced by chemical co-precipitation route (CR).Transmission Electron Microscopy (TEM) revealed that the as-deposited NPs exhibit a spherical morphology with core/shell structure and with diameters of (8 ± 4) nm (1064 nm) and (16 ± 5) nm (λ = 532 nm) for PLD approach, while for the CR, diameters of 8.0 ± 0.3 and 18.0 ± 0.3 nm were obtained for pure and SiO2-coated samples, respectively. X-Ray diffraction technique with Rietveld method was used to quantify the phases of oxidized NPs, and the percentages obtained were: 58% of Fe3O4 and 42% of α-Fe (532 nm) and 85% of Fe3O4 and 15% of α-Fe (1064 nm). For the samples obtained by CR, no spurious phase was observed in the diffractograms, only a very broad peak of SiO2 was observed around 25°, which indicates that the NPs were coated with SiO2, and this layer is amorphous. From Rietveld refinement, we found that the SiO2-coated sample has the highest Fetet-O-Feoct bond angle, which indicates a greater magnetic coupling between Fe atoms for these samples. Measurements of AC magnetization in different frequencies were carried out for all NPs and a detailed analysis of the dependence of the χ′ peak with T(K) helped to find out the relaxation time of the sample coated with SiO2 is 8.7 × 10−6 s, while for the other samples it was on the order of 10−9 s. Based on the results, it was possible to conclude that the coated sample presents a super spin-glass behavior, while in the other samples a magnetic interaction between NPs and oriented ferromagnetic clusters may be present.

The effect of 6 hours stirring time on natural iron sand base on magnetics Fe3O4 nanoparticle by sonification

In this research, ferrite magnetic nanoparticles (Fe3O4) from natural iron sand have been synthesized by co-precipitation technique with varying stirring time and sonification process. The purpose of this study was to determine the effect of 6 hours of synthesized magnetic nanoparticles (MNPs) on the resulting crystal size. The different structures and properties of the synthesized Fe3O4 nanoparticles were investigated using X-Ray Diffraction (XRD), Scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), and Energy Dispersion X-ray (EDX), respectively. XRD and SEM produced mean crystal sizes over the range of 13.93 nm and particle sizes of 14.8 nm. The EDX test explained that the Fe3O4 compound was successfully formed at 6.00 KeV. FTIR showed the element content of Fe-O at 555 cm-1. This study’s results indicate the MNPs synthesis process at 6 hours and the sonification process can produce Fe3O4 nanoparticles with a minimum size at the optimal time compared to synthesis at 8 hours, 7 hours, and 5 hours.

SYNTHESIS AND CHARACTERIZATION OF HEMATITE (Fe2O3) OF IRON ORE AND MAGNETITE (Fe3O4) FROM IRON SAND THROUGH PRECIPITATION METHOD FOR INDUSTRIAL RAW MATERIALS

Indonesia is a country that has enormous iron ore and iron sand mine that can be utilized for various industrial purposes. This research has been successfully conducted synthesis and characterization of hematite iron ore and magnetite from iron sand. Iron sand and iron ore that has been crushed manually repaired with a magnet was carried out with the HCl, and NH4OH then dried in the temperature of 150 oC and calcinated at a temperature of 500 oC. Characterization was carried out using X-ray diffraction (XRD) and X-ray fluorescence (XRF), where the preliminary information obtained from XRF results in an iron ore sample by manual separation have 95.99% of Fe2O3 and followed by compounds SiO2 (2.10%). While the iron sand contains 81.42% of Fe3O4 and 2.5% of SiO2. After the precipitation process, Fe2O3 compounds contained in iron ore has a content of 96.58% and Fe3O4 compounds contained in iron sand (86.73%). The results of XRD indicate the dominant primary phase in iron ore is hematite or Fe2O3, and in iron, sand is magnetite Fe3O4, Before the extraction process, Fe2O3 was 58.009 μm in size and after the process of extracting the particles was reduced to 20.950 μm. While the Fe3O4, prior to the extract, has a grain size of 59.009 μm, and after an extraction process, the grain size reduced into 25.950 μm. The calculation results indicate there is a slight size difference between the grain size of iron sand and iron ore.

Hierarchical Fe3O4-reduced graphene oxide nanocomposite grown on NaCl crystals for triiodide reduction in dye-sensitized solar cells

Cost-effective reduced graphene oxide sheets decorated with magnetite (Fe3O4) nanoparticles (Fe3O4-rGO) are successfully fabricated via a chemical vapor deposition (CVD) technique using iron (III) nitrate as an iron precursor, with glucose and CH4 as carbon sources, and NaCl as a supporting material. TEM analysis and Raman spectroscopy reveal hierarchical nanostructures of reduced graphene oxide (rGO) decorated with Fe3O4 nanoparticles. Fe K-edge x-ray absorption near edge structure (XANES) spectra confirm that the nanoparticles are Fe3O4 with a slight shift of the pre-edge peak position toward higher energy suggesting that the fabricated Fe3O4 nanoparticles have a higher average oxidation state than that of a standard Fe3O4 compound. The hierarchical Fe3O4-rGO is found to exhibit an excellent catalytic activity toward the reduction of triiodide to iodide in a dye-sensitized solar cell (DSSC) and can deliver a solar cell efficiency of 6.65%, which is superior to a Pt-based DSSC (6.37%).

Characterization of magnetite (Fe3O4) minerals from natural iron sand of Bonto Kanang Village Takalar for ink powder (toner) application

This research is about magnetite’s characterization (Fe3O4) from natural iron sands of Bonto Kanang Village, District of Takalar for ink powder (toner) application. This study aims to determine the process parameters to obtain magnetite of high purity degree and to observe its physical characteristics as a supporting toner material which synthesized through co-precipitation method. The iron sand was first separated by the magnetic technique and dissolved into HCl solution before conducting the precipitation process. Precipitation was done by dripping ammonium hydroxide (NH4OH). The precipitated powder was dried at 100°C, and then calcined at 400°C. The purity degree and magnetite mineral grain size were analyzed by XRD and SEM-EDS. The EDS elemental test before and after precipitation shown an increase of iron oxide composition from 66.70% to 87.76%. Diffractogram of XRD before and after precipitation showed Fe3O4 compounds with magnetite phase of 59% and 98%, respectively. The crystal structure iron sand powder structure before and after precipitation is cubic with each lattice parameters a = b = c = 8.384971 Å, V = 589.528423 Å3 and a = b = c = 8.386829 Å and V = 589.920291 Å3 when angle α = β = γ = 90°. SEM images (using SE and HV 20kV) showed inhomogeneous magnetite morphology. The magnetite phase percentage that obtained based on the XRD analysis gives information that magnetite precipitation has been successfully performed with high degree of purity. The material obtained can be applied as a support toner material.

Microwave-shielding behavior of silanized Cu and Cu–Fe3O4 compound particle-reinforced epoxy resin composite in E-, F-, I-, and J-band frequencies

In this work, microwave-shielding behavior of epoxy thermosetting plastic reinforced with silanized Cu and Cu–Fe3O4 compound particles were studied in frequency bands E, F, I, and J. The principal aim of this work is to evaluate the significant advantage of surface-modified magnetic and conductive fillers over as-received fillers in microwave shielding. The conductive and magnetic properties of epoxy resin were improved by additions of Cu and Fe3O4 particles. Compound particles of Cu–Fe3O4 were produced by mechanical alloying process (ball milling). The compound particles were surface treated by 3-Aminopropyltrimethoxysilane (APTMS) for better dispersion in epoxy resin matrix. Functional groups on particle’s surface after silane surface treatment were confirmed by FT-IR spectra analysis. The TEM images revealed that effective Cu–Fe3O4 particle compounding was formed at 1 h milling time. The maximum dielectric constant of 6.8 and magnetization of 675E−6 were observed for surface-modified compound particle-reinforced epoxy composite designation RCF2. Similarly, maximum microwave attenuation of 35% (44 dB) was observed for surface-modified compound particle-reinforced composite designation RCF2 in ‘J’-band frequency.

One-pot Synthesis and Surface Modification of Fe3O4 Nanoparticles Using Polyvinyl Alcohol by Coprecipitation and Ultrasonication Methods

Among the various substances developed through nanoparticles, iron oxide (Fe3O4) nanoparticle is one of the substances that have been widely used in various fields such as industry, agriculture, biotechnology and biomedicine. The synthesis of Fe3O4 nanoparticle can be carried out by two methods, consist of chemical and mechanical synthesis methods. Coprecipitation is one of the most commonly used methods for chemical synthesis. Fe3O4 compounds are easily oxidized because they are amphoteric. To avoid the continuous oxidation process, chemical modification process should be carried out with the addition of a solution of polyvinyl alcohol (PVA). In this study, PVA-coated Fe3O4 nanoparticles were synthesized by in-situ coprecipitation and ultrasonication methods through direct mixing (one-pot synthesis) of the iron (II) chloride tetrahydrate (FeCl2.4H2O), iron (III) chloride hexahydrate (FeCl3.6H2O), and PVA under alkaline condition. The effects of addition amount of NH3solution (by adjusting its flow rate using automated syringe pump) and PVA concentration were gently studied. Interaction of PVA with Fe3O4 nanoparticle was identified by infrared spectroscopy whereas lattice parameters and crystallite sizes of the synthesized Fe3O4 nanoparticles and PVA-coated Fe3O4 nanoparticles were assessed by X-ray diffraction (XRD).

Unmodified Fe3O4 nanostructure promoted with external magnetic field: safe, magnetically recoverable, and efficient nanocatalyst for N- and C-alkylation reactions in green conditions

Transition metal compounds have emerged as suitable catalysts for organic reactions. Magnetic compounds as soft Lewis acids can be used as catalysts for organic reactions. In this report, the Fe3O4 nanostructures were obtained from Fe2+ and Fe3+-salts, under an external magnetic field (EMF) without any protective agent. The X-ray photoelectron spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy tools were used to characterize these magnetic compounds. The two-dimensional (2-D, it showed nanometric size in the two dimensions, nanorod structure) Fe3O4 compound showed high catalytic activity and stability in N- and C-alkylation reactions. A diverse range of N- and C-alkylation products were obtained in moderate to high yield under green and mild conditions in air. Also the N- and C-alkylation products can be obtained with different selectivity and yield by exposure reactions with EMF. Results of alkylation reactions showed that the presence of Fe(II) and Fe(III) species on the surface of magnetic catalysts (phase structure of magnetic compounds) are essential as very cheap active sites. Also, morphology of magnetic catalysts had influence on their catalytic performances. After the reaction, the catalyst/product(s) separation could be easily achieved with an external magnet and more than 95% of catalyst could be recovered. The catalyst was reused at least four times without any loss of its high catalytic activity for N- and C-alkylation reactions.

Structure and Properties of Nanostructured YBa2Cu3O7–δ, BiFeO3, and Fe3O4

The development of new nanostructured materials based on YBa2Cu3O7–δ, BiFeO3, and Fe3O4 compounds is considered. The structure, morphology, and properties of these materials are studied. The possibilities of fabricating YBa2Cu3O7–δ ceramics with given densities from nanopowders in a single stage by an energy efficient method and growing superconducting films of the same composition on a silicon substrate (on a SiO2 layer) are demonstrated. The technique for fabricating BiFeO3 nanopowder, making it possible to obtain nanostructured ceramics without additional accompanied phases commonly forming during BiFeO3 synthesis is developed. Two methods of the single-stage synthesis of Fe3O4 nanopowder are presented: burning of nitrate-organic precursors and the electrochemical three-electrode method in which one of the electrodes, i.e., an anode containing scrap iron and slurry, is used as an expendable material.

Mössbauer study of oxide films of Fe-, Sn-, Cr- doped zirconium alloys during corrosion in autoclave

Mossbauer investigations were used to compare iron atom states in oxide films of binary Zr-Fe, ternary Zr-Fe-Cu and quaternary Zr-Fe-Cr-Sn alloys. Oxide films are received in an autoclave at a temperature of 350–360 °C and at pressure of 16.8 MPa. The corrosion process decomposes the intermetallic precipitates in alloys and forms metallic iron with inclusions of chromium atoms α–Fe(Cr), α–Fe(Cu), α–Fe 2O3 and Fe 3O4 compounds. Some iron ions are formed in divalent and in trivalent paramagnetic states. The additional doping influences on corrosion kinetics and concentration of iron compounds and phases formed in oxide films. It was shown the correlation between concentration of iron in different chemical states and corrosion resistance of alloys.

Study on Ginger Extract Performance as Corrosion Inhibitor in Acid and Neutral Environments

Study about organic inhibitor has been performed to analyze effect of ginger extract concentration (Zingiber officinaler) to corrosion characteristic of API 5L grade steel under 3.5% NaCl and 0.1M HCl. Amount of 100 to 500 ppm inhibitor injected into each solution and electrochemistry tests were performed. Ginger extract has been prepared previously with maceration method and tested with FTIR to identify type compound in it. Tafel test result showed that corrosion rate of steel decreased in accordance with the increase of inhibitors concentration. Corrosion rate decreased to 12.13 mpy at 500 ppm inhibitor under NaCl solution, with efficiency 54.79%. While in HCl, corrosion rate showed similar trend, with corrosion rate 8.19 mpy at 500 ppm, with efficiency 81.66%. EIS result showed that impedance increased with the increase of inhibitors concentration, while FTIR result showed that ginger extract inhibitor contain 2-Methoxy-4-propylphenol which is known as antioxidant compound. According to XRD test, Fe2O3 and Fe3O4 compound were identified on steel surface. Ginger extract might worked better in acid environment since it decrease corrosion rate significantly compared to neutral solution.

Changes in the state of iron atoms in Zr alloys during corrosion tests in an autoclave

Mossbauerinvestigations were carried out on oxide films formed on specimens of zirconium alloys Zr-1.0 %wtFe-1.2 %wtSn-0.5 %wtCr subjected to corrosion in steam-water environment at a temperature of 360 °C and at a pressure of 16.8 MPa with lithium and boron additions, and on Zr-1.4 %wtFe-0.7 %wtCr corroded in steam-water environment at 350 °C and 16.8 MPa as well as in steam-water environment at 500 °C and 10 MPa. In the metal part of the samples, under the oxide film, the iron atoms are in form of intermetallic precipitates of Zr(Fe, Cr)2. The corrosion process decomposes the intermetallic precipitates and particles are formed of metallic iron with inclusions of chromium atoms –Fe(Cr), α–Fe2O3 and Fe3O4 compounds. Part of the iron ions are in divalent and part in trivalent paramagnetic states. It is proposed that some part of the iron containing oxide precipitates in the oxide film may be in the form of nanoparticles which pass from the superparamagnetic to the ferromagnetic state with decreasing temperature.