Exchange bias and Verwey transition in Fe5C2/Fe3O4 core/shell nanoparticles

M. Xing; Jeotikanta Mohapatra; J. Elkins; D. Guragain; S. R. Mishra; J. Ping Liu

doi:10.1039/D1NR04520B

You do not have JavaScript enabled. Please enable JavaScript to access the full features of the site or access our non-JavaScript page.

Exchange bias and Verwey transition in Fe₅C₂/Fe₃O₄ core/shell nanoparticles†

M. Xing,^a Jeotikanta Mohapatra,

^a J. Elkins,^a D. Guragain,^b S. R. Mishra^b and J. Ping Liu*^a

Author affiliations

* Corresponding authors

^a Department of Physics, The University of Texas at Arlington, Arlington, Texas 76019, USA
E-mail: pliu@uta.edu
Tel: +1-817-272-2815

^b Department of Physics and Materials Science, The University of Memphis, Memphis, TN 38152, USA

Abstract

This report presents new findings of exchange bias and related structural and magnetic properties in iron carbide/magnetite (Fe₅C₂/Fe₃O₄) core/shell nanoparticles. The exchange bias emerges from an energetic landscape, namely a first-order phase transition–the Verwey transition at 125 K, during which the Fe₃O₄ shell changes from the cubic to monoclinic structure. The phase transition leads to the exchange bias because it results in abrupt changes in magnetocrystalline anisotropy and exchange coupling. Another unique phenomenon identified in this composite system is enhanced magnetic coercivity due to the uniaxial anisotropy of the monoclinic phase. An analysis of the correlations between the observed phenomena is given based on the temperature dependence of the coercivity, the exchange bias field values, and the Verwey transition temperature.

Download options Please wait...

Supplementary files

Supplementary information PDF (338K)

Article information

DOI: https://doi.org/10.1039/D1NR04520B
Article type: Paper
Submitted: 12 Jul 2021
Accepted: 05 Sep 2021
First published: 06 Sep 2021

Download Citation

Nanoscale, 2021,13, 15837-15843

Permissions

Request permissions

Exchange bias and Verwey transition in Fe₅C₂/Fe₃O₄ core/shell nanoparticles

M. Xing, J. Mohapatra, J. Elkins, D. Guragain, S. R. Mishra and J. Ping Liu, Nanoscale, 2021, 13, 15837 DOI: 10.1039/D1NR04520B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Social activity

Fetching data from CrossRef.
This may take some time to load.

Nanoscale