| Popis: |
The conventional ceramic double sintering method was used to prepare a series of mixed Li-Zn spinel ferrites (SFs) Direct electric (DC) electrical conductivity (σ) and inductance (L) were studied for the prepared series of samples from room temperature to well beyond the Curie point (TC). σ was measured as a function of temperature, the relation between lnσ with 1/T indicated that σ was increased with increasing of the temperature, which proves that the prepared samples have a semiconductor behavior. The maximum value of the σ was reported for the sample of x = 0.8. The σ results were interpreted in terms of hopping model. The relation between lnσT and 1/T showed a change in the slope which is attributed to the change of samples from ferrimagnetic to paramagnetic at TC. The values of L increased exponentially from room temperature up to TC, and then they decreased sharply. The calculated activation energy Ea in the ferromagnetic region was less than that in paramagnetic region. The calculated activation energy (Ea) decreased with increasing of Zn content. The values of the TC for the prepared samples were determined from σ and L measurements, which decreased with increasing of Zn content. The conventional ceramic double sintering method was used to prepare a series of mixed Li-Zn spinel ferrites (SFs) Direct electric (DC) electrical conductivity (σ) and inductance (L) were studied for the prepared series of samples from room temperature to well beyond the Curie point (TC). σ was measured as a function of temperature, the relation between lnσ with 1/T indicated that σ was increased with increasing of the temperature, which proves that the prepared samples have a semiconductor behavior. The maximum value of the σ was reported for the sample of x = 0.8. The σ results were interpreted in terms of hopping model. The relation between lnσT and 1/T showed a change in the slope which is attributed to the change of samples from ferrimagnetic to paramagnetic at TC. The values of L increased exponentially from room temperature up to TC, and then they decreased sharply. The calculated activation energy Ea in the ferromagnetic region was less than that in paramagnetic region. The calculated activation energy (Ea) decreased with increasing of Zn content. The values of the TC for the prepared samples were determined from σ and L measurements, which decreased with increasing of Zn content. |
