Giant magnetic moment enhancement of nickel nanoparticles embedded in multiwalled carbon nanotubes
Abstract
We report a giant magnetic moment enhancement of ferromagnetic nickel nanoparticles (11 nm) embedded in multiwalled carbon nanotubes (MWCNTs). High-energy synchrotron x-ray diffraction experiment and chemical analysis are used to accurately determine the ferromagnetic nickel concentration. Magnetic measurements show that the room-temperature saturation magnetization of the nickel nanoparticles embedded in the MWCNTs is enhanced by a factor of about 3.4±1.0 as compared with what they would be expected to have for free nanoparticles. The giant moment enhancement is unlikely to be explained by a magnetic proximity effect but possibly arise from the interplay between ferromagnetism in nickel nanoparticles and strong diamagnetism in multiwalled carbon nanotubes.
- Publication:
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Physical Review B
- Pub Date:
- November 2010
- DOI:
- Bibcode:
- 2010PhRvB..82s3410W
- Keywords:
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- 75.50.Tt;
- 61.48.De;
- 81.05.U-;
- Fine-particle systems;
- nanocrystalline materials;
- Structure of carbon nanotubes boron nanotubes and closely related graphitelike systems