Carbon nanotubes loaded with magnetic particles

Abstract

We describe a simple and versatile technique to produce magnetic tubes by filling carbon nanotubes (CNTs) with paramagnetic iron oxide particles (∼10 nm diameter). Commercial ferrofluids were used to fill CNTs with an average outer diameter of 300 nm made via chemical vapor deposition into alumina membranes. Transmission electron microscopy study shows a high density of particles inside the CNT. Experiments using external magnetic fields demonstrate that almost 100% of the nanotubes become magnetic and can be easily manipulated in magnetic field. These one-dimensional magnetic nanostructures can find numerous applications in nanotechnology, memory devices, optical transducers for wearable electronics, and in medicine. © 2005 American Chemical Society.