| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1785914 | Current Applied Physics | 2014 | 7 Pages |
•We find the existence of CuO-rich grain boundary segregation in NiCuZn ferrite after the sintering process.•Phase segregation makes the present ferrite electrically heterogeneous giving rise to dielectric relaxation process.•The relaxation principally originates from heterogeneity and has Maxwell–Wagner origin.
The present work investigates the polarization response in polycrystalline Ni0.9−yCuyZn0.1Fe1.98O4−δ (y = 0, 0.1, 0.2, 0.3, 0.4, 0.5) ferrite synthesized by solid–state reaction method. X-ray diffraction analysis confirmed cubic spinel phase formation in the calcined samples. Sintered samples contain a continuous network of CuO-rich segregation along the grain boundaries for y ≥ 0.2. Dielectric spectra showed a relaxation peak for y ≥ 0.2 in the frequency range of 1 kHz–1 MHz. This relaxation has been explained based on Maxwell–Wagner polarization considering two-layer model in connection with two heterogeneous dielectric media.
