Papers by Keyword: Fe₃O₄ Nanoparticle

Abstract: Novel multifunctional core shell structure CdTe-Fe₃O₄@CS drug nanocarriers were developed. The water soluble Fe₃O₄ nanoparticle was prepared by chemical coprecipitation method. The highly fluorescent CdTe QDs were prepared by refluxing method. The prepared Fe₃O₄ and CdTe QDs nanoparticles were capped with chitosan by ionic gel method to form multifunctional nanomaterials. After processing parameters affecting the end product properties were systematically optimized, folic acid, a model drug, was successfully incorporated into the polymeric complex.

Abstract: Cellulose nanocomposite is one of the most fascinating materials with broad applications. In this work, cellulose-magnetite nanocomposite has been prepared by dispersion of magnetite nanoparticles in a homogenous ionic liquid solution of grafted cellulose. Bagasse cellulose was first grafted with polymethacrylic acid in 1-butyl-3-methylimidazolium, and then fabricated with Fe3O4 nanoparticles during the homogeneous media. The obtained nanocomposite contained high content of iron due to the clelation of the grafted cellulose and Fe3O4 nanoparticles. It also exhibited superparamagnetic behavior with 8.606 emu/g saturation magnetizations. The cellulose-magnetite nanocomposite will be potential for the development of functional cellulose and protective materials for electromagnet radiation or microwaves.

Abstract: Novel Fe₃O₄/ordered mesoporous carbon (OMC) composite powders have been prepared by impregnation and reduction methods for the microwave absorbing application purpose. The Fe₃O₄ nanoparticles were encapsulated in the mesopores of OMCs, and Fe₃O₄ contents in the composite could be easily controlled by changing the concentration of ferric nitrate solution during the preparation. The Fe₃O₄/OMC composites show very excellent microwave absorbing properties with respect to pure OMC samples, in a frequency ranging of 8.2-12.4 GHz. A minimum reflection loss (RL) value of -32 dB at 11.35 GHz and a broader absorption band with the RL values under -10 dB are obtained when the thickness of samples is 1.6 mm. The enhanced microwave absorption of the Fe₃O₄/OMC nanocomposites is contributed to the better impedance match between dielectric loss and magnetic loss, which originates from the incorporation of magnetic species into OMC.

Abstract: Al-pillared bentonite supported Fe₃O₄ nanoparticles were prepared by co-precipitation and characterized with X-ray diffraction (XRD), specific surface area (BET) and scanning electron microscopy (SEM). The supported Fe₃O₄ nanoparticles exist on the surface of clays, with better dispersing and no obvious aggregation than the ones without bentonite support. Batch tests were carried out to investigate the catalytic oxidation Orange II by the obtained heterogeneous catalysts. The effect of pH, temperature and initial H₂O₂ concentration on degradation was discussed, and the regeneration ability of catalyst was also studied.

Abstract: We present an approach of synthesizing magnetic polyglycidyl methacrylate (PGMA) microspheres by a simple method of dispersion polymerization. Water-based Magnetic fluids which have different surface properties disperse in reaction system. The magnetic microspheres are appropriate to construct liquid chip carriers. In this work, citric acid-modified and citric acid sodium-modified magnetic nanoparticles for the preparation of magnetic microspheres are investigated. SEM results indicated that the magnetic microspheres have an average diameter of 3.78 μm with excellent monodispersity (PDI 1.09). Magnetization curve of Fe3O4 nanoparticles using superconducting quantum magnetometer showed their good performance in magnetic response characteristics. Chemical structures and crystal form of magnetic Fe3O4 were characterized and analyzed using FT-IR and XRD methods.

Abstract: In this paper, nano-Fe3O4 as sorbent was used to remove Congo red dye from aqueous solution, in order to investigate its adsorption properties. Fe3O4 nano-particles were synthesized by hydrothermal method, and were characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray Powder Diffraction (XRD) to examine their size, morphology and property. The adsorption and removal of Congo red dye from aqueous solution on nano-Fe3O4 was studied in batch equilibrium experiments. These results showed an excellent adsorption capability for Congo red with a maximum adsorption capacity of 1395mg•g-1 at 20°C and pH2.0. It indicates that Fe3O4 nano-particles can be effectively used to remove color from wastewater containing dyes.

Abstract: By using microbial reduction combining natural oxidation method, magnetic Fe₃O₄ nanoparticles have been synthesized. Sulfate-reducing bacterium(SRB) was used to reduce ferric sulfate to produce ferric sulfide, then ferric sulfide was oxidized to iron protoxide and ferroferric oxide in the end under natural air oxidation condition. The size and morphology of the product and SRB was examined by scanning electron microscopy(SEM), the microstructure were investigated by X-ray diffraction(XRD) and energy dispersive spectroscopy(EDS). There are only two components(xFeO and yFe₃O₄)which is testified by XRD and EDS. The constituents of product were analysed by using energy dispersive spectroscopy(EDS). In result, x,y actual numerical value which is respectively mole fraction of FeO and Fe₃O₄ in the product is figured out 0.678 and 0.322.

Abstract: The expanded graphite coated with different portions of Fe₃O₄ nanoparticles (EG/ Fe₃O₄) were synthesized by a simple hydrothermal reaction and the composite was characterized by scanning electron micrograph (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR). The catalytic performance of the composite was studied through the degradation of methylene blue. The results indicated that a complete and uniform Fe₃O₄ nanoparticles coating on expanded graphite could be obtained under routine pressure and temperature and the optimum content of Fe₃O₄ in the composite was 6wt% in the experiment of catalytic degradation of methylene blue.

Abstract: A facile chemical approach of preparing magnetic Fe₃O₄ nanoparticles with controlled sizes was developed by microwave-assisted co-precipitation method. By changing the synthetic conditions, particle diameter can be tuned from 9.6 to 19 nm. The results indicate that the hydrothermal temperature (HT) and consequent aging time play important roles in controlling of the particle size and crystallization.

Abstract: . Fe3O4 nanoparticles were synthesized and doped into two glass systems (Na2O-B2O3 glass and PbO-Bi2O3-B2O3-GeO2 glasses) at low concentrations using traditional glass melting method. The formation of Fe3O4 nanoparticles was obtained through coprecipitation of Fe(II) and Fe(III) in alkaline media.The size of the Fe3O4 nanoparticles was observed to be around 15 nm. The structure and properties of doped glasses were studied by X-ray diffraction (XRD), scanning electric microscope (SEM), UV-VIS spectray, FT-IR spectray analysis and Faraday rotation test. Compared to the host glass, Fe3O4 nanoparticles doped glasses shown enhanced Faraday Effect in term of Verdet constant and will have potential application in magneto-optical devices.