Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-30T23:37:18.843Z Has data issue: false hasContentIssue false
  • English
  • Français

Magnetism and Recoilless Fraction of Cerium-Doped Hematite Nanoparticles System

Published online by Cambridge University Press:  26 February 2011

Monica Sorescu  and
Lucian Diamandescu
Monica Sorescu
Affiliation:
[email protected], Duquesne University, Physics, 600 Forbes Ave, Pittsburgh, PA, 15282, United States, (412) 396-4166, (412) 396-4829
Lucian Diamandescu
Affiliation:
[email protected], National Institute for Materials Physics, Materials Science, Bucharest, 77125, Romania
Get access

Abstract

Cerium-doped hematite particles of the type xCeO2-(1-x)α-Fe2O3 (x=0.1, 0.5) were synthesized using mechanochemical activation and characterized by X-ray diffraction (XRD) and Mössbauer spectroscopy. XRD patterns yielded the dependence of lattice parameters and particle size as a function of ball milling time for each value of the molar concentration x. For x=0.1, the Mössbauer spectra were fitted with one or alternatively, two sextets, corresponding to Ce ions substituting Fe ions in the hematite structure. For x=0.5, Mössbauer spectra fitting required the addition of a quadrupole-split doublet, representing Fe substituting Ce in the CeO2 lattice. We evidenced this transition using our recently developed method for precise determination of the recoilless fraction in a single room-temperature transmission Mössbauer measurement of a two-absorber sample. We observed the occurrence of a minimum in the values of the recoilless fraction for t=4 hours of milling, followed by a further decrease of the f factor due to the appearance of nanoparticles in the system.

Keywords

mechanical alloyingmagnetic propertiesx-ray diffraction (XRD)
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1032: Symposium I – Nanoscale Magnetic Materials and Applications , 2007 , 1032-I14-13
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Gopel, W., Sens. Actuators B 18–19, 1 (1994).Google Scholar
2. Yamazoe, N., Miura, N., Sens. Actuators B 20, 95 (1994).10.1016/0925-4005(93)01183-5Google Scholar
3. Tamaki, J., Naruo, C., Yamamoto, Y., Matsuoka, M., Sens. Actuators B 83, 190 (2002).10.1016/S0925-4005(01)01039-5Google Scholar
4. Jiang, J. Z., Liu, R., Nielsen, K., Poulsen, F. W., Berry, F. J., Clasen, R., Phys. Rev. B 55, 11 (1997).10.1103/PhysRevB.55.11Google Scholar
5. Jiang, J. Z., Liu, R., Nielsen, K., Morup, S., Dam-Johansen, K., Clasen, R., J. Phys. D: Appl. Phys. 30, 1459 (1997).Google Scholar
6. Zhu, W., Tan, O. K., Jiang, J. Z., J. Mater. Electron. 9, 275 (1998).10.1023/A:1008820605197Google Scholar
7. Tan, O. K., Zhu, W., Yan, Q., Kong, L. B., Sens. Actuators B 65, 361 (2000).10.1016/S0925-4005(99)00414-1Google Scholar
8. Reddy, C. V. Gopal, Cao, W., Tan, O. K., Zhu, W., Sens. Actuators B 81, 170 (2002).10.1016/S0925-4005(01)00948-0Google Scholar
9. Cassedanne, J., An. Bras. Cienc. 38, 265 (1966).Google Scholar
10. Takano, H., Bando, Y., Nakanishi, N., Sakai, M., Okinaka, H., J. Solid State Chem. 68, 153 (1987).10.1016/0022-4596(87)90298-2Google Scholar
11. Sorescu, M., Mater. Lett. 54, 256 (2002).10.1016/S0167-577X(01)00572-9Google Scholar