Core/shell Nanostructures Due To Ce Into CoFe2O4 Induce Lattice And Vibrational Defects For Magnetic And Dielectric Enhancement

¹Centre of Advanced Study in Physics, Department of Physics, Panjab University, Chandigarh 160014, India

²CSIR-National Physical Laboratory, New Delhi 110012, India

Adv. Mater. Lett., 2016, 7 (8), pp 622-629

DOI: 10.5185/amlett.2016.6278

Publication Date (Web): Jul 01, 2016

Copyright © IAAM-VBRI Press

E-mail: kuldeep0309@yahoo.co.in , dkuldeep.physics@gmail.com

Abstract

We reported the Core/Shell structures of CoFe_2-xCe_xO₄ (CFCeO) nanoparticles were prepared by a chemical combustion method. The Rietveld refinement of X-ray diffraction pattern results into CoFe2O4 spinel structure and thevariation in lattice parameters have been found with doping of Ce ions. Transmission Electron Microscopy analysis has shown Core/Shell type nanoparticles. The stoichiometric composition of Co, Fe, Ce and O atoms has been analyzed through X-ray fluorescence elemental detection. Fourier transform infrared spectra could detect organic extent, tetrahedral (Fe-O), octahedral (Fe(Ce)-O-Co) and lattice disorder in CFO nanoparticles with Ce doping. Defects related oxygen vacancies are analyzed in Photoluminescence emission spectra. The room temperature magnetic measurement of CFO nanoparticles is highly influenced with Ce ions. The magnetic interactions are antiferromagnetic at room temperature that confirmed by zero field cooling and field cooling magnetic measurements at 100 Oe. However, the spin glass and ferromagnetic clustered growth may also exist in CFCeO samples that reduce room temperature ferromagnetism. The dielectric measurement indicates polarization up to higher frequency region that enhanced with Ce ions.

Keywords

Core/shell nanoparticles, magnetism, chemical combustion, rietveld refinement, defects.