Nanocomposites (NCs) comprising BiFeO3(BFO) and CoFe2O4(CFO) with nominal composition, x CoFe2O4- (1-x) BiFeO3(x = 0.2, 0.3 and 0.4) have been synthesized adopting a sol-gel route. XRD patterns of the prepared samples exhibit presence of both BFO and CFO crystalline phases. TEM images of the NCs show that particles are mostly spherical with size in the range 15–25 nm. Room temperature Mössbauer spectra of the pristine samples and NCs reveal presence of Fe3+ions at different inequivalent sites of BFO and CFO. Room temperature dc magnetization measurements show significant enhancement in magnetization of the NCs compared to that of the pristine BFO. Variation of dielectric constant of the NCs with frequency shows a dispersive behavior in low frequency region which is attributed to grain boundary relaxation in the NCs. εr– T curves of all samples exhibit an anomaly near the antiferromagnetic transition temperature of BFO indicating presence of magnetoelectric (ME) coupling. Variation of capacitance of the NCs in presence of external magnetic field confirms an improvement of ME coupling in BFO after formation of the NCs.
|Number of pages||8|
|Journal||Journal of Alloys and Compounds|
|State||Published - 2017|
Bibliographical noteFunding Information:
The author A. Das thanks University Grants Commission (UGC), New Delhi, for providing Senior Research Fellowship. Authors would like to thank Mr. Binoy Krishna Hazra, School of Physics, University of Hyderabad, for high temperature dielectric measurements. Authors acknowledge Department of Science and Technology, India (Project no. IR/S2/PU-06/2006) for low temperature high magnetic field facility at UGC-DAE Consortium for Scientific Research, Kolkata Centre.
© 2016 Elsevier B.V.
- Mössbauer spectroscopy