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Study of structural, morphological, Mössbauer and dielectric properties of NiFeCoO4 prepared by a sol gel method
Authors: A. Omri, E. Dhahri, B.F.O. Costa, M.A. Valente
Ref.: J. Sol-Gel Sci. Technol. 98, 364-375 (2021)
Abstract: A methodical study on structural, electrical and dielectric properties of NiFeCoO4 nanoparticles, synthesized via sol-gel technique has been reported in this article. X-ray diffractogram confirmed phase purity of the synthesized sample. Raman spectra show the five predicted Raman bands that appear around 600–720, 250–360, 500–590, 450–520 and 180–220 cm−1 corresponding to A1g, Eg, T2g (3), T2g (2) and T2g (1), respectively. From the dielectric measurements, we have determined the different dielectric parameters such as the conductivity σac, complex permittivity ε*, complex impedance Z*, and the tangent loss (tanδ). The electrical properties strongly depend on temperature and frequency. The relaxation activation energy deduced from the Z” vs. frequency plots was similar to the conduction activation energy obtained from the conductivity. Hence, the same type of charge carriers are attributed to the relaxation process and the conduction mechanism. The complex impedance plots have revealed the presence of only one semicircular arc corresponding to grains and grain boundaries contributions at all the temperatures and an equivalent electric circuit was proposed as a model of the sample.
