Structural, Ferroelectric, Magnetic and Magnetoelectric Response in Multiferroic (1-x)Bi(Ni1/2Ti1/2)O3-PbTiO3/xNi0.6Zn0.4Fe2O4 Particulate Composites

TL;DR

This study investigates multiferroic composites combining ferroelectric and magnetic phases, revealing structural changes, magnetic behavior evolution, and significant magnetoelectric effects, highlighting their potential for multifunctional device applications.

Contribution

It introduces a new multiferroic composite with tunable properties and demonstrates a large magnetoelectric response, advancing multifunctional material development.

Findings

Tetragonality increases with magnetic phase concentration, indicating ionic diffusion.

Superparamagnetic behavior observed in ferroelectric-rich compositions.

Large magnetoelectric coefficient of 30 mV/Oe-cm demonstrated in the composite.

Abstract

Multiferroic particulate composites have been fabricated by taking the morphotropic phase boundary composition of ferroelectric phase Bi(Ni1/2Ti1/2)O3-PbTiO3 and magnetic phase (Ni,Zn)Fe2O4. The ferroelectric phase has coexisting monoclinic and tetragonal perovskite structures with space group Pm and P4mm, respectively whereas the magnetic phase has spinel cubic structure with space group Fd3m. Rietveld structural analysis for the each components of composite reveals that the tetragonality (c/a) of the ferroelectric phase continuously increases with increasing the concentration of magnetic phase suggesting partial ionic diffusion between ferroelectric and magnetic phases, after composite formation. Composition dependent M\"ossbauer spectra of (1-x)Bi(Ni1/2Ti1/2)O3-PbTiO3/x(Ni,Zn)Fe2O4 reveals the superparamagnetic like behavior for the ferroelectric rich composition with x=0.2. The magnetic ordering increases for the composition with x=0.4 and 0.6 which completely transform into ferrimagnetic for the composition with x=0.9 for the magnetic phase rich compositions. Unlike the ferroelectric or magnetic components which do not exhibit the magnetoelectric response separately, large value of magnetoelectric coefficient (30 mV/Oe-cm) in (1-x)Bi(Ni1/2Ti1/2)O3-PbTiO3/xNi0.6Zn0.4Fe2O4 composite makes it promise for multifunctional applications.