Journal article
High coercivity of iron-filled carbon nanotubes synthesized on austenitic stainless steel
Dipartimento di Fisica, Università di Roma “Tor Vergata”, 00133 Roma, Italy1
INSTM – Unità di ricerca di Roma “Tor Vergata” – Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma “Tor Vergata”, 00133 Roma, Italy2
Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 44322 Nantes, France3
Unità CNISM – Dipartimento di Fisica, Università di L’Aquila, 67010 L’Aquila, Italy4
Multiwalled carbon nanotubes synthesized directly on austenitic stainless steel result in being filled with pure iron nanoparticles. X-ray diffraction shows that the nanoparticles are either in the γ- or α-phase, although iron in the original alloy is in γ-phase because of the presence of nickel. This phase transformation is due to the selective extraction of iron, performed by carbon nanotubes during their growth.
A high coercivity of iron-filled carbon nanotubes is measured although the starting steel is paramagnetic. The presence of the α-phase, the magnetic anisotropy and the single domain character of the Fe nanoparticles explain their magnetic behavior.
Language: | English |
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Year: | 2011 |
ISSN: | 18733891 and 00086223 |
Types: | Journal article |
DOI: | 10.1016/j.carbon.2011.09.034 |