Dielectric Anomalies and Competing Magnetic Interactions in NiFe2O4–PMN–PT Nanocomposite Materials

Abstract

We report on dielectric anomalies, competing magnetic interactions and relaxor ferroelectric behaviors of xPMN–PT–(1 – x)NiFe2O4 (x = 0.2 and 0.4) nanocomposites. The crystal structure and surface morphology of the pure and composite nanomaterials were examined by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Phase formation and purity of the NiFe2O4, PMN–PT and the composites were confirmed from XRD measurements. Uniformly distributed nanoparticles and nanowires and the presence of Ni, Fe, O, Pb, Nb, Mg, and Ti in NiFe2O4 and PMN–PT are confirmed from FESEM and energy dispersive X-ray (EDX) measurements. Structural disordering due to phase transition around 453 K in both composites was examined from temperature variation Raman studies. Magnetization measurements at room temperature and at 40 K, zero field cooled (ZFC) and field cooled (FC) magnetization measurements for both composites were carried out from 2 to 350 K. Competing magnetic interacti...