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Updated: Jun 22, 2026

Biofunctionalization of Magnetic Nanomaterials
Published on: July 16, 2020
Attachment of magnetite nanoparticles on carbon nanotubes bundles and their response to magnetic fields
F Marquez1, C Morant, J M Sanz
1Departamento de Física Aplicada, C-XII, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain.
Abstract:
We present an alternative method to control the alignment of carbon nanotube bundles by applying an external magnetic field on magnetic nanoparticles functionalized nanotubes. Carbon nanotubes have been modified by pi-pi stacking of a carboxylic acid and the previously synthesized Fe3O4 nanoparticles have been bounded to the acid groups. Results obtained by TEM, SEM and FESEM show that the magnetite nanoparticles are distributed along the nanotube surfaces, showing a high dispersion and a mean particle size of ca. 4-5 nm. In presence of a magnetic field the modified nanotube bundles have been clearly oriented along the axis parallel to the field.
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