A thermodynamic model for growth mechanisms of multiwall carbon nanotubes.

Journal Article · Tue Jan 31 23:00:00 EST 2006 · Proposed for publication in Applied Physics Letters.

DOI:https://doi.org/10.1063/1.2405847· OSTI ID:952166

Kaatz, Forrest H; Overmyer, Donald L; Siegal, Michael P

Multiwall carbon nanotubes are grown via thermal chemical vapor deposition between temperatures of 630 and 830 C using acetylene in nitrogen as the carbon source. This process is modeled using classical thermodynamics to explain the total carbon deposition as a function of time and temperature. An activation energy of 1.60 eV is inferred for nanotube growth after considering the carbon solubility term. Scanning electron microscopy shows growth with diameters increasing linearly with time. Transmission electron microscopy and Raman spectroscopy show multiwall nanotubes surrounded by a glassy-carbon sheath, which grows with increasing wall thickness as growth temperatures and times rise.

• Research Organization: Sandia National Laboratories
• Sponsoring Organization: USDOE
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 952166
• Report Number(s): SAND2006-0979J
• Journal Information: Proposed for publication in Applied Physics Letters., Journal Name: Proposed for publication in Applied Physics Letters.
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACETYLENE
ACTIVATION ENERGY
CARBON
CARBON SOURCES
CHEMICAL VAPOR DEPOSITION
DEPOSITION
NANOTUBES
NITROGEN
RAMAN SPECTROSCOPY
SCANNING ELECTRON MICROSCOPY
SOLUBILITY
THERMODYNAMIC MODEL
THERMODYNAMICS
THICKNESS
TRANSMISSION ELECTRON MICROSCOPY