Complex impedance and magnetoelectric effect analyses of a novel three-ply-structured (Tb_0.3Dy_0.7)_0.75Pr_0.25Fe_1.55-Pb(Zr_0.53Ti_0.47)O₃nanoceramic composites

New magnetoelectric (ME) three-ply-structured nanoceramic composites consisting of nano-sized alloy-based magnetostrictive and ferroelectric powders were fabricated successfully by a conventional ceramic process. X-ray diffraction patterns exhibited the presence of the constituent phases in the composite. Transmission electron microscopy (TEM) showed the metal particles mainly located at the intergrain and the grain boundaries of the ferroelectric particulates. Temperature dependent complex impedance analysis was carried out to distinguish the grain-grain, grain-boundary, electrode-electrolyte effects, and discerned the contribution from insulating and interlaid layers in the new three-layer-structure. The AC conductivity was independence of frequency between 10 Hz and 200 kHz measured at room temperature; while the DC resistivity had a value over 1010Ω·cm and was only slightly varied with the metal content. A stable ME effect was found in the frequency range of 1-150 kHz except for the resonance region. The maximumαEwas ∼32 mV cm-1Oe-1at a resonance frequency of around 111 kHz.