Universität Wien

Single Wall Carbon Nanotubes

SWCNT (6,4), parallel to axis SWCNT (6,4), perpendicular to axis

The strongest and toughest material known so far with very low specific gravity

High application potential:

Nanoelectronics, transistors
Nanoelectronics, contact leeds
Field emission for dispaly or as general electron source
Sensor technology
Thermoelectric applications
Reinforcement in compound materials
Antistatic filler
Nonlinear optical filter
Nanoscale mechanics
Nanoscope tips

Single Wall Carbon Nanotubes (SWCNTs)

Properties of CNTs
Diameter [nm]0.4 – 1.6 SWCNTs
 5 – 100 MWCNTs
Density [g/cm3]1.3 – 1.4
Young‘s modulus [TPa]0.6 (10,10) tube
 0.3 – 1.5 SWCNT ropes
Tensile strength [GPa]45 SWCNT ropes
Specific heat [J/gK]0.7
Thermal conducivity [W/mK]>3000 individ. MWCNT
Thermoelectric power [mV/K]60
Field emission theshold [V/m] 2x10^6
Max current density [A/cm2] > 10^7
DOS at Fermi level 0 or 8/3paCCg_0
Overlap integral g_0 [eV] 2.9 from optics

Bandstructure of graphene

First Brillouin zone (graphene) and k-space (NTs) Metallic NT (left) Semiconducting NT (right)

Bandstructure of SWCNTs

Van Hove singularities in the DOS

Electron Microscopy and Raman Scattering of SWCNTs

SWCNT bundles, Thess et al. Science 1996

MWCNT Iijima et al. Science 1991

Important Raman modes

RBM: radial breathing mode, ~ 200 cm-1, dispersive
D: defect mode, ~1350 cm-1, dispersive
G: graphitic modes, 1540 – 1590 cm-1
G‘: overtone of D mode, ~2700 cm-1, dispersive

Quantum Oscillation of RBM, Milnera et al. PRL 2000