Electrical conductivity of some nickel-zinc ferrites

Abstract

The electrical conductivity of some nickel-inc ferrites is studied as a function of temperature. The ferrites with iron in excess show n-type conduction and those with iron in deficiency show p-type conduction. Seebeck coefficient, X-ray analysis, and saturation magnetisation are also carried out to discuss the conductivity of these ferrites.Es wird die elektrische Leitfihigkeit einiger Nickel-Zinkferrite als Funktion der Temperatur gemessen. Ferrite mit EisenfiberschuD zeigen n-Leitfihigkeit, solche mit Eisenmangel p-Leitfiihigkeit. Untersuchungen des Seebeckkoeffizienten, der SLttigungsmagnetisiernng sowie Riintgenanalysis werden durchgefiihrt, um die Leitfiihigkeit dieser Ferrite zu diskutieren.

Finite size effect and influence of temperature on electrical properties of nanocrystalline Ni–Cd ferrites

“…Due to these size effects the conductivity of the samples of 4 and 3 nm is smaller. Moreover, it is seen that the value of the activation energy for the grain size of 5 nm is found to be 0.31 eV, which indicates that below 5 nm the conduction process is due to the holes, i.e., ferrites formed are p-type semiconductors [22,23], as a result the value of activation energy are also found to increase on the basis of Verwey conduction mechanism [24]. The scattering due to the grain boundary dominates; in addition to electrical resistivity and the temperature coefficient of materials are increased if the size of the crystallite is smaller than the electron mean free path.…”

Thermoelectric power studies of Ca–Co ferrites

“…produced across the sample due to the temperature difference T. The electrical conductivity of the samples has been measured at room temperature by a two-probe method [4] using a Keithley electrometer model 6517A. The electrical conductivity (σ) of the Ca-Co ferrites under investigation has been computed using the formula,…”

Structural, optical and dielectric properties of Ni substituted NdFeO3

“…Therefore, substitution of trivalent Fe with homovalent Ni involves an increased number of interactions in the system which may effect their structural, optical and other transport properties of the system. The transport properties of Ni substituted NFO and other ferites are thoroughly studied by many researchers [15][16][17]. However, not much attention has been paid on the optical and dielectric properties of NFO in which Fe is replaced with Ni.…”