Shape dependent multiferroic behavior in Bi2Fe4O9nanoparticles

Aditi Sahoo; Dipten Bhattacharya; Moumita Das; Prabhat Mandal

doi:10.1088/1361-6528/ac667d

Shape dependent multiferroic behavior in Bi₂Fe₄O₉nanoparticles

Nanotechnology. 2022 May 4;33(30). doi: 10.1088/1361-6528/ac667d.

Authors

Aditi Sahoo¹, Dipten Bhattacharya¹, Moumita Das², Prabhat Mandal²

Affiliations

¹ CSIR-Central Glass & Ceramic Research Institute, Kolkata 700032, India.
² Saha Institute of Nuclear Physics, Kolkata 700064, India.

PMID: 35413693
DOI: 10.1088/1361-6528/ac667d

Abstract

Ferroelectric and magnetic properties are investigated for Bi₂Fe₄O₉nanoparticles with different shapes (cuboid and sphere-like) synthesized by hydrothermal and sol-gel method. The magnetic study reveals that coercivity, Neel temperature and remanent magnetization strongly depend on shape of the particle. The nanoparticle with sphere-like shape exhibits magnetization curve of antiferromagnetic (AFM) ordering with ferromagnetic (FM) component. As the particle shape changes from sphere-like to cuboid, the AFM component is dominating over the ferromagnetic component. A small exchange bias is also observed at low temperature in both the sphere-like and cuboid nanoparticle. The coercivity, remanent magnetization and Neel temperature of sphere-like nanoparticle is greater than cuboid nanoparticle. Ferroelectric measurement shows the remanent polarization of cuboid is greater than sphere-like nanoparticle but the coercivity is almost same. This Bi₂Fe₄O₉nanoparticle shows a small change in polarization under magnetic field. The polarization value decreases with magnetic field increases. The magnetoelectric coupling-measured by change of remanent polarization under magnetic field are found to be greater in Bi₂Fe₄O₉sphere-like nanoparticles. These shape dependent magnetic and ferroelectric properties are coming because of shape anisotropy.

Keywords: Bi2Fe4O9 nanoparticle; ferroelectricity; magnetism; magnetoelectric coupling; shape anisotropy.