Modeling, simulation and synthesis of multiferroic magnetoelectric CoFe2O4/BaTiO3 composite nanoparticles
Introduction
Multiferroic magnetoelectric (ME) composites are important and have attracted much attention due to their interesting new physics and potentials for exploring novel multifunctional devices [1]. These materials possess significant role in the electronic, magnetic and optical properties. Multiferroic magnetoelectric materials are used in many industrial applications, such as sensors, read heads, nonvolatile memory elements, nano-electronics and memories based on giant magnetoresistive effects [[2], [3], [4], [5]].
Among multiferroic magnetoelectric (ME) nanocomposites, cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) nanoparticles have an important advantage due to the spinodal decomposition of this binary system, which prevents reaction between the constituents during high-temperature processing [6,7]. They have been extensively used for numerous applications, such as electro-magnetic interference filters, capacitors, transducers, integral chip inductors [[8], [9], [10]], spintronics, memory, and sensors [[11], [12], [13], [14]].
Various fabrication methods such as wet chemical synthesis [[15], [16], [17]], co-precipitation [18,19], thermal decomposition, hydro/solvo thermal synthesis, sol-gel method [16,20], microemulsion, combined hydrothermal and annealing processes [21], ball milling method [8], etc. have been reported for preparing CoFe2O4/BaTiO3 nanoparticles.
The optical and magnetic properties of multiferroic magnetoelectric (ME) nanocomposites are currently of considerable interest, due to their wide applications in sensors, capacitors, transducers and memory. Among multiferroic magnetoelectric (ME) nanoparticles, cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) nanoparticles have been substantially studied due to their fascinating optical and magnetic properties and quantum confinement effect. The optical absorption of cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) nanoparticles is affiliated to electronic structure in terms of an inter-band electronic excitation from the valence band to the conduction band. The optical properties of the CoFe2O4/BaTiO3 nanoparticles can be precisely tuned by changing the core size, shell thickness as well as the core and shell shapes. Moreover, it is well recorded that ferroelectric properties of BaTiO3 and ferromagnetic properties of CoFe2O4 depend on particle size [6,22,23]. Correspondingly, one should anticipate a size impact on the magnetoelectric coupling in the composites.
In this research, we discuss the optical properties of cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) nanoparticles of various sizes and compare the predicted properties based on quantum mechanical principles using density functional theory (DFT) with the experimentally observed results, assisted via the finite element simulations using COMSOL Multiphysics. Moreover, we investigated the ferromagnetic behavior of the CoFe2O4/BaTiO3 nanoparticles.
Section snippets
Theoretical background
The most evolved model on light scattering and absorption by particles stems from Gustav Mie in 1908 [24,25]. This theory describes the quasi-elastic interaction between an electromagnetic plane wave and a homogeneous sphere defined by its (arbitrary) diameter and its (arbitrary) complex refractive index. It allows one to calculate scattered fields outside the sphere, internal fields, phase relations and various cross sections, including for radiation pressure forces [26].
Mie explained the
Materials and methods
The CoFe2O4/BaTiO3 magnetoelectric nanoparticle composites were synthesized employing a sol-gel technique [35,36]. The CoFe2O4 nanoparticles used were obtained from commercial sources MKnano Sales and US Research Nanomaterials, Inc. Barium carbonate (BaCO3)/DI water and titanium isopropoxide (Ti(OCH(CH3)2)4)/ethanol-based citrate solutions were prepared, and a precursor BaTiO3 solution was synthesized. The CoFe2O4 nanoparticles were dispersed in the precursor solution, vigorously sonicated, and
TEM image
Transmission Electron Microscopy image of barium titanate/cobalt ferrite nanoparticles is taken with a TEM model no. JEOL2010F. Fig. 2 shows the TEM image and size distribution of CoFe2O4/BaTiO3 nanoparticles.
XRD analysis of CoFe2O4/BaTiO3 nanoparticles
The crystalline structure of CoFe2O4/BaTiO3 nanoparticles was characterized by XRD.
Fig. 3 shows the XRD patterns of CFO:BTO core-shell nanocomposites consist of two single phases, i.e., a CFO core with a cubic spinel structure and a BTO shell with a tetragonal perovskite structure.
The mean
Conclusions
COMSOL multiphysics software package and density functional theory (DFT) model have been employed to determine the absorption spectra of CoFe2O4/BaTiO3 nanoparticles and compared to the values observed experimentally. For nanoparticles of 8 nm and 9 nm in dimension, it is found that both DFT and COMSOL produce similar predictions in terms of absorption peak maxima.
The numerical modeling of DFT simulation compared well with the experimental results. DFT model has been found to create more
Author statement
Elham Gharibshahi: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Resources, Data curation, Writing – original draft, Writing – review & editing, Visualization, Supervision, Project administration. Brandon D. Young: Methodology, Validation, Investigation, Formal analysis, Resources. Amar S. Bhalla: Writing – review & editing, Project administration, Supervision. Ruyan Guo: Writing – review & editing, Project administration, Supervision, Funding acquisition.
Declaration of competing interest
The authors declare that they have no conflict of interest.
Acknowledgments
This research work has been partially supported by the Office of Naval Research (ONR), United States of America (USA), under the grant number N00014-16-1-3096.
References (45)
- et al.
Acta Mater.
(2012) - et al.
Acta Mater.
(2015) - et al.
NPG Asia Mater.
(2010) - et al.
Acta Mater.
(2010) - et al.
J. Magn. Magn Mater.
(2010) - et al.
J. Magn. Magn Mater.
(2007) Prog. Solid State Chem.
(1979)- et al.
Superlattice. Microst.
(2013) - et al.
Ceram. Int.
(2015) - et al.
Mater. Chem. Phys.
(2009)
J. Phys. Chem. Solid.
J. Mater. Sci. Technol.
Nat. Mater.
In, ACS Publications
J. Phys. Condens. Matter
Sci. Rep.
In: 2011 Symposium on Piezoelectricity, Acoustic Waves and Device Applications (SPAWDA)
Appl. Phys. Lett.
J. Phys. Appl. Phys.
Adv. Mater.
Nanoscale
Sci. Rep.
Cited by (6)
Investigations on low temperature magnetic and magnetoelectric properties of multiferroic-NiO nanocomposites
2023, Journal of Alloys and CompoundsMultiferroic perovskite ceramics: Properties and applications
2022, Perovskite Ceramics: Recent Advances and Emerging ApplicationsSintering of layered ferrite-BaTiO<inf>3</inf> ceramics: Analysis of interfaces and effects of shrinkage mismatch
2022, Processing and Application of Ceramics