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arXiv · 1004.1151

Iron oxide doped boron nitride nanotubes: structural and magnetic properties

Ronaldo J. C. Batista·Alan B. de Oliveira·Daniel L. Rocco
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Abstract

A first-principles formalism is employed to investigate the interaction of iron oxide (FeO) with a boron nitride (BN) nanotube. The stable structure of the FeO-nanotube has Fe atoms binding N atoms, with bond length of roughly $\sim$2.1 Å, and binding between O and B atoms, with bond length of 1.55 Å. In case of small FeO concentrations, the total magnetic moment is (4$μ_{Bohr}$) times the number of Fe atoms in the unit cell and it is energetically favorable to FeO units to aggregate rather than randomly bind to the tube. As a larger FeO concentration case, we study a BN nanotube fully covered by a single layer of FeO. We found that such a structure has square FeO lattice with Fe-O bond length of 2.11 Å, similar to that of FeO bulk, and total magnetic moment of 3.94$μ_{Bohr}$ per Fe atom. Consistently with experimental results, the FeO covered nanotube is a semi-half-metal which can become a half-metal if a small change in the Fermi level is induced. Such a structure may be important in the spintronics context.

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Ronaldo J. C. Batista, Alan B. de Oliveira, Daniel L. Rocco. 2010-05-26. Iron oxide doped boron nitride nanotubes: structural and magnetic properties. https://doi.org/10.1088/0953-8984%2F22%2F35%2F355302

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