Electronic properties of FeCl3-intercalated single-wall carbon nanotubes

Abstract

The electronic properties of ${\mathrm{FeCl}}_{3}$ intercalated single-wall carbon nanotubes were investigated using high-resolution electron energy-loss spectroscopy in transmission and optical spectroscopy. The lowering of the nanotube Fermi level is directly measured via electronic excitations from C $1s$ to empty carbon $2p$ states derived from the doping. The charge induced disappearance of the optically allowed transitions is demonstrated by the evolution of the optical absorption spectrum. In the loss function the appearance of a new feature can be assigned to plasmon excitations. The optical properties of ${\mathrm{FeCl}}_{3}$ intercalated nanotubes are comparable with those of fully potassium doped nanotubes. Upon annealing, the intercalant can be removed reversibly.