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

Abstract

This study was aimed to study the effect of Zn content on the hyperfine parameters and the structural variation of Ni 1-x Zn x Fe 2 O 4 for x = 0, 0.2, 0.4, 0.6, and 0.8. To achieve this, a sol-gel route was used for the preparation of samples and the obtained ferrites were investigated by X-ray diffraction, scanning electron microscopy, and Mössbauer spectroscopy. The formation of spinel phase without any impurity peak was identified by X-ray diffraction of all the samples. Moreover, the estimated crystallite size by X-ray line broadening indicates a decrease with increasing Zn content. This result was in agreement with the scanning electron microscopy result, indicating the reduction in grain growth with further zinc substitution. The room-temperature Mössbauer spectra show that the hyperfine fields at both the A and B sites decreased with increasing Zn content; however, the rate of reduction is not the same for different sites. Moreover, the best fit parameter showed that the quadrupole splitting values of B site increased from the pure nickel ferrite to the sample with x = 0.8.

Magnetism and Structure Evolution in Ni-Zn Ferrites Thin Films - CEMS Study

“…When x = 0 (a) the spectrum is typical of the ferromagnetic inverse NiFe 2 O 4 spinel and consist of two Zeeman sextets A and B0, corresponding to tetrahedral A and octahedral B sites of Fe, respectively. In most of the references the sextet of higher hyperfine field is attributed to B position [3][4][5] (Table I) are lower by 5-8% than those reported in literature [3][4][5][6] for respective bulk materials, which is a sign of thermal magnetic relaxation effects in thin layers -like in the case of Ni-Zn ferrites nanoparticles [7,8]. In CEMS spectrum obtained for x = 0.2 zinc content besides B0 and A sextets (with small variance ∆B hf of hyperfine field distribution) the broadened sextet BN occurs which corresponds to the iron in B sites possessing n = 1−3 Zn neighbors in the nearest A sites (instead of Fe) [6].…”

“…The structural and magnetic order were effectively studied by means of transmission Mössbauer spectrometry in bulk [3][4][5][6] and nanocrystalline [7,8] Ni-Zn ferrites. In this work, a conversion electron Mössbauer spectrometry (CEMS) and X-ray diffraction (XRD) have been utilized for the investigation of structural and magnetic order in 500 nm thick Ni 1−x Zn x Fe 2 O 4 (0 ≤ x ≤ 1) ferrite films deposited on Si(100) substrate by laser ablation.…”