Iron oxide nanoparticles and VOx/Hexadecylamine nanotubes composite

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:320

Article; Proceedings Paper

Saleta, M. E.¹  Troiani, H. E.¹  Guevara, S. Ribeiro¹  Sanchez, R. D.¹  Malta, M.²  Torresi, R. M.³ 

[1] Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina

[2] Univ Estado Bahia, Dept Ciencias Exatas & Terra, Salvador, BA, Brazil

[3] Univ Sao Paulo, Inst Quim, BR-05513970 Sao Paulo, Brazil

关键词: magnetic properties of nanostructures;    vanadium oxide nanotube;    nanocomposite;    EPR;    TEM;   

DOI  :  10.1016/j.jmmm.2008.02.088

来源: Elsevier

【 摘 要 】

In this work, we present the synthesis and characterization of a hybrid nanocomposite constituted by iron oxide nanoparticles and vanadium oxide/Hexadecylamine (VOx/Hexa) nanotubes. Transmission Electron Microscopy (TEM) images show small particles (around 20 nm) in contact with the external wall of the multiwall tubes, which consist of alternate layers of VOx and Hexa. By Energy Dispersive Spectroscopy (EDS), we detected iron ions within the tube walls and we have also established that the nanoparticles are composed of segregated iron oxide. The samples were studied by Electron Paramagnetic Resonances (EPR) and dc-magnetization as a function of the magnetic field. The analysis of the magnetization and EPR data confirms that a fraction of the V atoms are in the V4+ electronic state and that the nanoparticles exhibit a superparamagnetic behavior. The percentage of V and Fe present in the nanocomposite was determined using Instrumental Neutron Activation Analysis (INAA). (C) 2008 Elsevier B.V. All rights reserved.

【 授权许可】

Free