X-ray absorption and photoelectron spectroscopy studies on graphite and single-walled carbon nanotubes: Oxygen effect
Abstract
We have investigated the electronic states of highly oriented pyrolitic graphite and single-walled carbon nanotubes using x-ray absorption spectroscopy (XAS) before and after annealing treatment in ultrahigh vacuum, and observed that the small peak between π* and σ* features, which has been previously assigned to free-electron-like interlayer states, disappears after in situ annealing treatment, suggesting that the signal may be assigned to a surface contamination, especially oxygen contamination introduced by chemical processing or gas adsorption. Additional experiments by photoelectron spectroscopy as well as XAS methods, performed after aging in air, fully support this interpretation.
- Publication:
-
Applied Physics Letters
- Pub Date:
- August 2005
- DOI:
- 10.1063/1.2006214
- Bibcode:
- 2005ApPhL..87e1923A
- Keywords:
-
- 81.05.Uw;
- 81.07.De;
- 78.70.Dm;
- 79.60.Jv;
- 71.20.Tx;
- 81.40.Gh;
- 81.40.Cd;
- 81.65.-b;
- 68.43.Mn;
- Carbon diamond graphite;
- Nanotubes;
- X-ray absorption spectra;
- Interfaces;
- heterostructures;
- nanostructures;
- Fullerenes and related materials;
- intercalation compounds;
- Other heat and thermomechanical treatments;
- Solid solution hardening precipitation hardening and dispersion hardening;
- aging;
- Surface treatments;
- Adsorption/desorption kinetics