Synthesis, characterization and effects of citric acid and PVA on magnetic properties of CoFe2O4

Cobalt ferrite (CoFe2O4) particles were synthesized by sol-gel method using metal nitrates, citric acid (CA) and polyvinyl alcohol (PVA). X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), thermogravimetry/differential scanning calorimetry analysis and vibrating sample magnetometer were used to study the structural, thermal and magnetic properties of the CoFe2O4 powder. XRD results indicate that the resultant particles have crystalline, pure single phase spinel structure. From HR-SEM images, a systematic decrease in particle size is observed with an increase in PVA concentration, along with addition of CA. CA at various concentrations of PVA significantly enhance the magnetic properties of the materials

Effect of TEA on the structural and magnetic properties of ferromagnetic ZnFe2O4 nanoparticles

Ferromagnetic ZnFe2O4 nanoparticles were synthesized by surfactant assisted hydrothermal method using different amount of triethylamine (TEA). The synthesized nanoparticles were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution transmission electron microscopy and vibrating sample magnetometer. The formation of single phase ZnFe2O4 was investigated by addition of different amount of TEA. Regular spinel structure was obtained for all synthesized product except for lower amount of TEA, owing to the less alkaline atmosphere. All the synthesized nanoparticles were spherical in shape with a small aggregation. Observed size of the nanoparticles was 10 nm as determined from TEM measurement for the sample synthesized with a higher amount of TEA. Room temperature ferromagnetic behavior was observed in all the samples

Study of CoFe2O4 particles synthesized with various concentrations of PVP polymer

CoFe2O4 particles were synthesized using metallic nitrates and polyvinylpyrolidone (PVP) using sol-gel method followed by calcination for 2 h at 960 C. PVP performed as a surfactant and the effect of various concentrations of PVP on the resultant CoFe2O4 powder was studied. The resultant samples were characterized by XRD, TG/DSC, HR-SEM and VSM. X-ray diffraction results indicated the crystalline phase of CoFe2O4 particles and impurity phase of hematite was observed for higher PVP concentrations. SEM images demonstrated the influence of PVP concentration on the size of the particles. By VSM measurements, the variations in magnetic properties with respect to PVP concentration are studied. All the magnetic characteristics H c, M s and M r increased for 6 wt% and 15 wt% of PVP concentration. The CoFe 2O4 particles synthesized with the optimum concentration of PVP may be very attractive for potential applications because of their outstanding magnetic properties (M s =81.1 Am2/kg, H c =831 Gauss)

Study of CoFe2O4 particles synthesized with various concentrations of PVP polymer

CoFe2O4 particles were synthesized using metallic nitrates and polyvinylpyrolidone (PVP) using sol-gel method followed by calcination for 2 h at 960 C. PVP performed as a surfactant and the effect of various concentrations of PVP on the resultant CoFe2O4 powder was studied. The resultant samples were characterized by XRD, TG/DSC, HR-SEM and VSM. X-ray diffraction results indicated the crystalline phase of CoFe2O4 particles and impurity phase of hematite was observed for higher PVP concentrations. SEM images demonstrated the influence of PVP concentration on the size of the particles. By VSM measurements, the variations in magnetic properties with respect to PVP concentration are studied. All the magnetic characteristics H c, M s and M r increased for 6 wt% and 15 wt% of PVP concentration. The CoFe 2O4 particles synthesized with the optimum concentration of PVP may be very attractive for potential applications because of their outstanding magnetic properties (M s =81.1 Am2/kg, H c =831 Gauss)

Hydrous ferric oxide-magnetite-reduced graphene oxide nanocomposite for detection of arsenic using surface plasmon resonance

Surface plasmon resonance sensor coated with hydrous ferric oxide-magnetite-reduced (Fe2H2O4-Fe3O4-rGO) graphene oxide nanocomposite film was demonstrated to detect two toxic heavy metals; Arsenic (III) [As(III)] and Arsenic (V) [As(V)] in aqueous solution. The proposed nanocomposite film exhibited successful absorption of As with enhanced sensitivity and selectivity. Resultantly, when tested with different concentrations of As(III) and As(V), (0.1-1.0 ppb) the sensor ranged linearly with sensitivity of 2.196 °ppb-1 and 0.960 °ppb-1, respectively, and achieved a detection limit as low as 0.1 ppb. These results validate the potential of Fe2H2O4-Fe3O4-rGO nanocomposite material for optical sensing applications in As detection

Effect of microwave sintering on microstructural and magnetic properties of strontium hexaferrite using sol-gel technique

The sol–gel method is used to prepared hexaferrite using d-Fructose as a fuel. The effect of sintering temperature on the microstructure of SrFe12O19 ceramics is analyzed. The observed XRD results indicate a well-formed crystalline phase of dense hexagonal SrFe12O19 ceramics. From this analysis, no secondary phases are identified. The microstructure of the sintered single phase M-type ferrites ceramics displays a hexagonal-platelet like morphology. Sintering temperature can markedly affect the grains in sintered ferrite. The sintered product is shown to be dense microstructure with relatively small grains. The maximum sintered density 95 % was obtained at lower temperature of 1,150 °C. In addition, saturation magnetization (50.43 emu/g) and the coercivity (Hc) 5,594.53 Gauss were observed

Synthesis, Characterization, and Cytotoxicity of Iron Oxide Nanoparticles

In order to study the response of human breast cancer cells' exposure to nanoparticle, iron oxide (α-Fe2O3) nanoparticles were synthesized by a simple low temperature combustion method using Fe(NO3)3·9H2O as raw material. X-ray diffraction studies confirmed that the resultant powders are pure α-Fe2O3. Transmission electron microscopy study revealed the spherical shape of the primary particles, and the size of the iron oxide nanoparticles is in the range of 19 nm. The magnetic hysteresis loops demonstrated that the sample exposed ferromagnetic behaviors with a relatively low coercivity. The cytotoxicity of α-Fe2O3 nanoparticle was also evaluated on human breast cancer cells to address the current deficient knowledge of cellular response to nanoparticle exposure