Effect of Zn doping on temperature and frequency dependence of dielectric permittivity and dielectric relaxation for synthesized tetragonal copper–gallium ferrite

Preparation and Characterization of Zinc-Containing Nickel Gallate Ferrite

“…The behavior of the samples is similar to that of most ferrites. 6,8,15 Dispersion behavior is observed for e¢ at low frequencies, and becomes frequencyindependent at high frequency. It is also observed from Fig.…”

“…[26][27][28] These results can be interpreted on the basis of the strong correlation between tan d and the type of conduction mechanism in the spinel ferrites. 8 The conduction mechanism is mainly depends on the hopping process in the octahedral B site, and a maximum loss peak is observed when the frequency of the external field is equal to the frequency of the hopping process. Ata-Allah 29,30 explained that both cation-cation and cation-anion-cation interactions occur in the spinel ferrite because of the presence of transition metal ions in the B sites.…”

“…10 considering that at the maximum loss xs = 1. 8,31 The activation energy E a can be calculated from a plot of ln s against the reciprocal of the absolute temperature Fig. 11; the values are listed in Table III.…”

“…Samples were pressed into pellets of diameter $1 cm and thickness $4 mm. 8 For measurement of electrical properties the two surfaces of each pellet were coated with silver paste and checked for good electrical contact. Figure 1 shows XRD spectra of the samples; these confirm that pure NiGaFeO 4 and Zn-doped Ni 1Àx Zn x GaFeO 4 occur as single spinel phases.…”

Electrical and Dielectric Relaxation Characterization of Ni1−x Zn x Ga0.5Fe1.5O4

“…Figure 8 shows that there are also abrupt changes in (ε ) at temperatures 558, 517, 496, 464, 433, and 405 K for x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, respectively. These changes related to a transformation from the ferromagnetic to the paramagnetic state [29]. The values of transition temperature T C obtained from Fig.…”