Magnetic and Dielectric Properties of Mg Substituted Nanocrystalline Li Ferrite Obtained by the Method Auto-Ignition Sol-Gel
The ultrafine particles of magnesium-substituted lithium ferrites of the general formula were synthesized by a low-temperature gel-citrate auto-combustion method. The structural characteristics of the samples were obtained on the basis of X-ray diffraction (XRD) and SEM (emission electron spectroscopy) analyzes. XRD studies have confirmed the formation of a single-phase spinel structure with crystallite sizes around 15 - 30 nm. The M-H loop was recorded using an F-64 ferrometer for all formulations at room temperature and 50 Hz and the hysteresis parameters obtained. The hysteresis loop of the obtained samples showed a clear saturation at the applied field ± 60 E and by its very nature the loop is very symmetrical. Dielectric parameters such as dielectric steel, resistivity (s) and conductivity of samples () were investigated as a function of frequency in the range of 0.01 Hz to 100 kHz and in the temperature range 293 - 493 K using an impedance spectrometer. The dielectric constant of the samples revealed a normal frequency dependence of the dielectric, indicating that the dispersion is due to the polarization of the boundaries of the Maxwell-Wagner type grains and the jump of the electron between ions.
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