Zn doped NiFe2O4- Pb (Zr0.58Ti0.42)O3 multiferroic nanocomposites: Magnetoelectric coupling, dielectric and electrical transport

Abstract

We have investigated the room temperature magnetoelectric coupling, temperature dependent impedance and dielectric properties of xZn0.3Ni0.7Fe2O4 – (1-x) Pb (Zr0.58Ti0.42)O3 (x = 0.2, 0.3, 0.4 and 0.5) nanocomposites. The nanocomposites have been prepared through low temperature chemical pyrophoric reaction process followed by solid state reaction route. The magnetoelectric coupling has been measured as a function of applied magnetic field at different frequencies and different angles between applied magnetic field and measured electric field. The observed magnetoelectric coupling may be due to the field dependent magnetostriction of the piezomagnetic phase of the composite. Noticeably, the magnetoelectric coupling is strongly depended on the frequencies, angles and volume fraction of the piezomagnetic phase of the nanocomposites. Polarization – Electric field loop shows the room temperature ferroelectric nature of nanocomposites. The ac electrical properties of the nanocomposites have been studied employing impedance spectroscopy technique. The temperature dependent impedance studies reveal the grain boundaries plays the dominating role. Thermally tunable dielectric properties of nanocomposites exhibit the Maxwell – Wagner interfacial polarization in the system. Electromechanical resonance response is observed at the higher frequency region. The ac conductivity of the nanocomposites has been investigated at different temperatures and fitted by Jonscher's power law. The conduction mechanism is mainly due to the small and large polaronic hopping in the system.