Colossal permittivity, resistive and magnetic properties of zinc substituted manganese ferrites

Experimental Investigations on the Electrical Conductivity and Complex Dielectric Permittivity of ZnxMn1−xFe2O4 (x = 0 and 0.4) Ferrites in a Low-Frequency Field

“…At the same time, the increas conductivity σDC with temperature is due to the increase in the drift mobility of the ch carriers, according to Mott's VRH (variable range hopping) conduction mechanism [1 In the case of sample B (Zn0.4Mn0.6Fe2O4), the conductivity σDC(T) increases when temperature increases from 30 °C to about 60 °C (Figure8b) and then decreases increasing temperatures from 60 °C to 128 °C. Thus, unlike the results published in [13], we highlighted that, around the temperature of 60 °C, there is a transition fro semiconductor behavior to a conductor behavior. In the low-temperature range, electrons are not free, and the conductivity increases with increasing temperatures, this behavior being a semiconductor-type behavior.…”

“…From Figure 8a, it can be seen that, in the case of sample A (MnFe2O4), the σD component increases slightly when the temperature increases from 30 °C approximately 70 °C, after which the increase is more pronounced at temperat between 70 °C and 127 °C, indicating that the conduction process is thermally activ over the two temperature ranges, as in Ref. [13]. At the same time, the increas conductivity σDC with temperature is due to the increase in the drift mobility of the ch carriers, according to Mott's VRH (variable range hopping) conduction mechanism [1 In the case of sample B (Zn0.4Mn0.6Fe2O4), the conductivity σDC(T) increases when temperature increases from 30 °C to about 60 °C (Figure8b) and then decreases increasing temperatures from 60 °C to 128 °C.…”

“…where D is given by the equation From Figure 8a, it can be seen that, in the case of sample A (MnFe 2 O 4 ), the σ DC (T) component increases slightly when the temperature increases from 30 • C to approximately 70 • C, after which the increase is more pronounced at temperatures between 70 • C and 127 • C, indicating that the conduction process is thermally activated over the two temperature ranges, as in Ref. [13]. At the same time, the increase in conductivity σ DC with temperature is due to the increase in the drift mobility of the charge carriers, according to Mott's VRH (variable range hopping) conduction mechanism [19].…”

“…where the round bracket and the square bracket represent the tetrahedral site (A-site) and the octahedral site (B-site), respectively [10]. The substitution of Mn 2+ with Zn 2+ ions in the tetrahedral site will lead to the improvement of the structural, morphological, magnetic, and electrical properties of Mn-Zn ferrite [11][12][13]. More researchers have obtained significant results regarding the obtaining methods, morpho-structural characterization, and magnetic properties of Mn-Zn compounds [14][15][16].…”

Enhancement in the dielectric and magnetic properties of Ni2+–Cu2+ co-doped BaFe11Cu1−xNixO19 hexaferrites (0.0 ≤ x ≤ 1.0)

“…Moreover, a dielectric relaxation peak was observed for all the samples, which indicates that the frequency at which electrons/holes hop between different ionic states is synchronized with the frequency of the applied alternating current. 29 However, as the Ni 2+ doping concentration increases, the observed peaks shied to a lower frequency, and the peak intensity decreased slightly. This peak shiing is due to the increased relaxation time of the polarizable entities in the prepared samples, which is inuenced by the presence of additional dipoles introduced by the Ni 2+ doping content.…”