About this Journal Submit a Manuscript Table of Contents
Advances in Materials Science and Engineering
Volume 2010 (2010), Article ID 715872, 14 pages
http://dx.doi.org/10.1155/2010/715872
Research Article

Critical Analysis on the Structural and Magnetic Properties of Bulk and Nanocrystalline Cu-Fe-O

1Materials Science Centre, Department of Nuclear Physics, University of Madras, Guindy Campus, Chennai 600 025, India
2Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
3Center for Study of Matter at Extreme Conditions, Florida International University, Miami, FL 33199, USA
4Lawrence Berkeley National Laboratory, Advanced Light Source, Berkeley, CA 94720, USA

Received 1 November 2010; Accepted 16 December 2010

Academic Editor: Jacques Huot

Copyright © 2010 D. Paul Joseph et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Nanocrystalline and bulk samples of “Fe”-doped CuO were prepared by coprecipitation and ceramic methods. Structural and compositional analyses were performed using X-ray diffraction, SEM, and EDAX. Traces of secondary phases such as CuFe2O4, Fe3O4, and α-Fe2O3 having peaks very close to that of the host CuO were identified from the Rietveld profile analysis and the SAED pattern of bulk and nanocrystalline Cu0.98Fe0.02O samples. Vibrating Sample Magnetometer (VSM) measurements show hysteresis at 300 K for all the samples. The ferrimagnetic Neel transition temperature ( 𝑇 𝑁 ) was found to be around 465°C irrespective of the content of “Fe”, which is close to the 𝑇 𝑁 value of cubic CuFe2O4. High-pressure X-Ray diffraction studies were performed on 2% “Fe”-doped bulk CuO using synchrotron radiation. From the absence of any strong new peaks at high pressure, it is evident that the secondary phases if present could be less than the level of detection. Cu2O, which is diamagnetic by nature, was also doped with 1% of “Fe” and was found to show paramagnetic behavior in contrast to the “Fe” doped CuO. Hence the possibility of intrinsic magnetization of “Fe”-doped CuO apart from the secondary phases is discussed based on the magnetization and charge state of “Fe” and the host into which it is substituted.