Electron spin resonance of carbon nanotubes
โ Scribed by Mayumi Kosaka; Thomas W. Ebbesen; Hidefumi Hiura; Katsumi Tanigaki
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 338 KB
- Volume
- 225
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
โฆ Synopsis
The electron spin resonance (ESR) of carbon nanotubes at various stages of purification have been measured between 4 and 296 K The conduction electron spin resonance is identified and the results imply that metallic and/or narrow gap semiconducting nanotubes are actually present as predicted by theory. From the temperature dependences of the ESR intensity, linewidth and g-value, the electronic properties of the observed nanotuhes are found to be similar to those of graphite.
๐ SIMILAR VOLUMES
The ESR was investigated for a series of samples of glassy carbon hear-treated to various temperatures in the range 10~~30~5C using a Q and X band spectrometers. For the sotid material, the width first increases slightly, then goes through a rninil~u~~~ at around 1400ยฐC and increases greatly above H
The electron spin resonance in nearly amorphous carbon has been studied. Amorphous carbon was produced by arc evaporation of spectroscopic pure graphite in argon atmosphere. Carbon deposits were collected and measurements performed without exposing samples to the air, as well as after admission of a
Carbon films deposited on Pyrex, silica and alumina substrates have free spin concentrations similar to those found for chars. The results of heat treatment show that a maximum in the spin concentration occurs at a heat treatment temperature of about 150ยฐC and that when silica and alumina substrates
Samples of P33 carbon black, heat treated in the range 1600"-26OO"C, were studied by E.P.R. The lineintensity, localized and free spins contributions, and g-factor, are examined as a function of residence time at H.T.T. (a few minutes to several hours). The correlation between the g-factor and diama