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Title: Size Dependent Magnetic Properties and Cation Inversion in Chemically Synthesized MnFe2O4 Nanoparticles

Abstract

MnFe{sub 2}O{sub 4} nanoparticles with diameters ranging from about 4 to 50 nm were synthesized using a modified coprecipitation method. X-ray diffractograms revealed a pure phase spinel ferrite structure for all samples. Transmission electron microscopy showed that the particles consist of a mixture of both spherical (smaller) and cubic (larger) particles dictated by the reaction kinetics. The Neel temperatures (T{sub N}) of MnFe{sub 2}O{sub 4} for various particle sizes were determined by using high temperature magnetometry. The {approx}4 nm MnFe{sub 2}O{sub 4} particles showed a T{sub N} of about 320 C whereas the {approx}50 nm particles had a T{sub N} of about 400 C. The high Neel temperature, compared with the bulk MnFe{sub 2}O{sub 4} T{sub N} of 300 C, is due to a change in cation distribution between the tetrahedral and octahedral sites of the spinel lattice. Results of extended x-ray absorption fine structure measurements indicate a systematic change in the cation distribution dependent on processing conditions.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930659
Report Number(s):
BNL-81141-2008-JA
Journal ID: ISSN 0021-8979; JAPIAU; TRN: US200901%%18
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; MANGANESE OXIDES; IRON OXIDES; NANOSTRUCTURES; MAGNETIC PROPERTIES; PARTICLE SIZE; COPRECIPITATION; CRYSTAL STRUCTURE; NEEL TEMPERATURE; national synchrotron light source

Citation Formats

Chinnasamy,C., Yang, A., Yoon, S., Hsu, K., Shultz, M., Carpenter, E., Mukerjee, S., Vittoria, C., and Harris, V. Size Dependent Magnetic Properties and Cation Inversion in Chemically Synthesized MnFe2O4 Nanoparticles. United States: N. p., 2007. Web. doi:10.1063/1.2710218.
Chinnasamy,C., Yang, A., Yoon, S., Hsu, K., Shultz, M., Carpenter, E., Mukerjee, S., Vittoria, C., & Harris, V. Size Dependent Magnetic Properties and Cation Inversion in Chemically Synthesized MnFe2O4 Nanoparticles. United States. doi:10.1063/1.2710218.
Chinnasamy,C., Yang, A., Yoon, S., Hsu, K., Shultz, M., Carpenter, E., Mukerjee, S., Vittoria, C., and Harris, V. Mon . "Size Dependent Magnetic Properties and Cation Inversion in Chemically Synthesized MnFe2O4 Nanoparticles". United States. doi:10.1063/1.2710218.
@article{osti_930659,
title = {Size Dependent Magnetic Properties and Cation Inversion in Chemically Synthesized MnFe2O4 Nanoparticles},
author = {Chinnasamy,C. and Yang, A. and Yoon, S. and Hsu, K. and Shultz, M. and Carpenter, E. and Mukerjee, S. and Vittoria, C. and Harris, V.},
abstractNote = {MnFe{sub 2}O{sub 4} nanoparticles with diameters ranging from about 4 to 50 nm were synthesized using a modified coprecipitation method. X-ray diffractograms revealed a pure phase spinel ferrite structure for all samples. Transmission electron microscopy showed that the particles consist of a mixture of both spherical (smaller) and cubic (larger) particles dictated by the reaction kinetics. The Neel temperatures (T{sub N}) of MnFe{sub 2}O{sub 4} for various particle sizes were determined by using high temperature magnetometry. The {approx}4 nm MnFe{sub 2}O{sub 4} particles showed a T{sub N} of about 320 C whereas the {approx}50 nm particles had a T{sub N} of about 400 C. The high Neel temperature, compared with the bulk MnFe{sub 2}O{sub 4} T{sub N} of 300 C, is due to a change in cation distribution between the tetrahedral and octahedral sites of the spinel lattice. Results of extended x-ray absorption fine structure measurements indicate a systematic change in the cation distribution dependent on processing conditions.},
doi = {10.1063/1.2710218},
journal = {Journal of Applied Physics},
number = ,
volume = 101,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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