Investigation of electrical transport in hydrogenated multiwalled carbon nanotubes

Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115, USA
Physica B Condensed Matter (Impact Factor: 1.32). 02/2011; 406(4):841-845. DOI: 10.1016/j.physb.2010.12.009


Highly disordered multiwalled carbon nanotubes of large outer diameter (∼60 nm) fabricated by means of chemical vapor deposition process inside porous alumina templates exhibit ferromagnetism when annealed in a H2/Ar atmosphere. In the presence of an applied magnetic field, there is a transition from positive to negative magnetoresistance. The transition may be explained in terms of the Bright model for ordered and disordered carbon structures. Additionally, temperature dependent electrical transport experiments exhibit a zero-bias anomaly at low temperature.

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Available from: Yung Joon Jung, Dec 23, 2013
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    • "In contrast to graphite and in spite of theoretical predictions on the possibility to have magnetic order due to hydrogen or vacancies in carbon nanotubes (CNT) [3] [4] [5], the observation of this phenomenon in these carbon structures appears to be more difficult. Apparently, only the hydrogenated CNT prepared in [6] [7] showed the existence of magnetic order at room temperature. However, and in clear contrast, several studies reported the existence of superconductivity through measurements in single nanotubes as well as bundles of them (single-and multiwall) [8– 15]. "
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