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Title: Magnetic Alloys in Nanoscale Biomaterials

Abstract

Fe-Co composition gradient and Fe-Pt multilayer alloy films were tested as catalysts for growing vertically aligned carbon nanofibers (VACNFs) by plasma-enhanced chemical vapor deposition (PECVD). The Fe-Co film yielded nanofibers with alloy tips in a wide compositional range varying from 8.15 pct Fe at the Co-rich end to 46.29 pct Fe in the middle of the wafer as determined by energy-dispersive X-ray analysis. Two Fe-Co cubic phases (SG Pm3m, Pm{bar 3}m) were identified by preliminary X-ray diffraction (XRD) measurements. Magnetic measurements showed a substantially greater hysteresis loop area and coercivity in Fe-Co catalyst nanoparticles as compared to the as deposited Fe-Co film. The Fe-Pt film did not break into FePt alloy nanoparticles under the applied processing parameters and thus the utility of FePt as a VACNF catalyst has been inconclusive.

Authors:
 [1];  [2];  [1];  [2];  [2];  [3];  [2];  [2];  [2];  [2]
  1. Florida Atlantic University
  2. ORNL
  3. University of Tennessee, Knoxville (UTK)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931344
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Metallurgical and Materials Transactions A; Journal Volume: 37A
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; CARBON; CATALYSTS; CHEMICAL VAPOR DEPOSITION; HYSTERESIS; PROCESSING; X-RAY DIFFRACTION

Citation Formats

Leventouri, T. H., Melechko, Anatoli Vasilievich, Sorge, Korey D., Klein, Kate L, Fowlkes, Jason Davidson, Rack, P. D., Anderson, Ian M, Thompson, James R, McKnight, Timothy E, and Simpson, Michael L. Magnetic Alloys in Nanoscale Biomaterials. United States: N. p., 2006. Web. doi:10.1007/s11661-006-1036-4.
Leventouri, T. H., Melechko, Anatoli Vasilievich, Sorge, Korey D., Klein, Kate L, Fowlkes, Jason Davidson, Rack, P. D., Anderson, Ian M, Thompson, James R, McKnight, Timothy E, & Simpson, Michael L. Magnetic Alloys in Nanoscale Biomaterials. United States. doi:10.1007/s11661-006-1036-4.
Leventouri, T. H., Melechko, Anatoli Vasilievich, Sorge, Korey D., Klein, Kate L, Fowlkes, Jason Davidson, Rack, P. D., Anderson, Ian M, Thompson, James R, McKnight, Timothy E, and Simpson, Michael L. Sun . "Magnetic Alloys in Nanoscale Biomaterials". United States. doi:10.1007/s11661-006-1036-4.
@article{osti_931344,
title = {Magnetic Alloys in Nanoscale Biomaterials},
author = {Leventouri, T. H. and Melechko, Anatoli Vasilievich and Sorge, Korey D. and Klein, Kate L and Fowlkes, Jason Davidson and Rack, P. D. and Anderson, Ian M and Thompson, James R and McKnight, Timothy E and Simpson, Michael L},
abstractNote = {Fe-Co composition gradient and Fe-Pt multilayer alloy films were tested as catalysts for growing vertically aligned carbon nanofibers (VACNFs) by plasma-enhanced chemical vapor deposition (PECVD). The Fe-Co film yielded nanofibers with alloy tips in a wide compositional range varying from 8.15 pct Fe at the Co-rich end to 46.29 pct Fe in the middle of the wafer as determined by energy-dispersive X-ray analysis. Two Fe-Co cubic phases (SG Pm3m, Pm{bar 3}m) were identified by preliminary X-ray diffraction (XRD) measurements. Magnetic measurements showed a substantially greater hysteresis loop area and coercivity in Fe-Co catalyst nanoparticles as compared to the as deposited Fe-Co film. The Fe-Pt film did not break into FePt alloy nanoparticles under the applied processing parameters and thus the utility of FePt as a VACNF catalyst has been inconclusive.},
doi = {10.1007/s11661-006-1036-4},
journal = {Metallurgical and Materials Transactions A},
number = ,
volume = 37A,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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