Mössbauer and magnetization studies of nickel ferrites

Abstract

Nickel ferrites have been produced by the rf plasma deposition technique for the first time. This technique has promise for large scale fine particle production of ferrites. Powder x-ray diffraction linewidth measurements show an average particle size of about 55 nm. Mossbauer measurements show the presence of both the nickel ferrite and the nickel zinc ferrite with Fe3O4 created in each ferrite production process as an impurity. Magnetization and Mössbauer measurements show evidence that the aerosol prepared samples have small particle characteristics as compared to solid state reacted bulk materials.

Mössbauer spectroscopy study of aluminium substituted nickel-ferrites

“…The component associated with the tetrahedral site also has a lower IS than that associated with the octahedral site, a behavior which is expected for a lower coordination number around the Fe cations in the tetrahedral sites. These results are in good agreement with the hyperfine parameters for NiFe 2 O 4 prepared by solid state reaction and rf plasma aerosol deposition reported by De Marco et al [4]. The relative intensities for the two sextet components in the spectrum of the sample with x = 0 (NiFe 2 O 4 ) are expected to be equal based on the inverse spinel structure of the Ni-ferrite.…”

“…Other several methods have recently been used to prepare Ferrites in fine particle form, i.e. co-precipitation method and combustion in urea [2], mechanochemical activation [3] and rf plasma aerosol deposition technique [4].…”

Mössbauer Spectroscopic Studies of NiZn Ferrite Prepared by the Sol-Gel Method

“…The magnetic hyperfine fields for sample with x = 0.0 are H hf (A) = 48.5 and H hf (B) = 52.9, which are comparable to those reported by De Marco et al for the pure nickel ferrite [34]. To explain the difference between H hf (A) and H hf (B), it is worthy to note that the magnetic hyperfine interaction not only depends on the different covalences of the Fe-O bond at the A and B sites, but also originates from the average magnetization of each sublattice.…”

Structural and magnetic properties of NiFe2−xBixO4 (x=0, 0.1, 0.15) nanoparticles prepared via sol–gel method

“…Their unique properties, for instance, an enhanced chemical reactivity, an enhanced magnetization, and an enhanced magnetic ordering temperature [2][3][4], make them attractive, both from the scientific and application points of view. There are various techniques to obtain MFe 2 O 4 nanoparticles such as hydrothermal reactions [5], coprecipitation [6], combustion synthesis [7], thermal decomposition [8], mechanosynthesis [9], microwave processing [10], electrospinning [11], the reverse micelle technique [12], the plasma deposition method [13], the radio-frequency thermal plasma torch technique [14], the pulsed wire discharge [15], sonochemical synthesis [16], and sol-gel method [17]. The latter method generally refers to the hydrolysis and the condensation of a metal nitrate or citrate, leading to dispersions of oxide particles in a ''sol''.…”