Composite BNT-BT0.08/CoFe2O4 with core-shell nanostructure for piezoelectric and ferromagnetic applications

摘要： In this work, we report on the synthesis and characterization of BNT-BT0.08/CoFe2O4 biphasic composite with core-shell structure. This artificial core (BNT-BT0.08)/shell (CoFe2O4) heterostructure was prepared by sol-gel method and the resulting composite was characterized in term of microstructure, dielectric, piezoelectric and magnetic properties. BNT-BT0.08/CoFe2O4 sintered ceramic shows high permittivity (ε′ ≥ 30) and high dielectric losses (tan δ ≥ 10) in the low frequency range (ν ≤ 104 Hz), remnant polarization (Pr) of ～7.7 μC/cm2 and, remanent magnetization (Mr) of 24 emu/g at 5 K and of 14 emu/g, at room temperature. The present study reveals that the ferroelectric, piezoelectric and magnetic properties of this new architectured composite depend on the amount of each component and, can be tailored by adjusting their synthesis conditions. BNT-BT0.08/CoFe2O4 core-shell material investigated in this work provides a novel way to exploit new applications for the multifunctional composite, such as piezoelectric sensor, magnetoelectronic sensors and data storage devices.