Isotopic fractionation during fullerene, nanotube, and nanopolyhedra formation

Journal Article · Wed Dec 01 04:00:00 EST 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00077a087· OSTI ID:5257244

Pallasser, R; Pang, L S.K.; Prochazka, L; Rigby, D; Wilson, M A ^[1]

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1. CSIRO Division of Petroleum Resources, North Ryde, NSW (Australia)

The production of fullerenes by electrical arcing or resistively heating produces a number of other products including nanotubes and nanopolyhedra, microtubes, and pyrolytic carbon. The mechanism of formation of these different products is still speculative. We report here that the isotopic distributions in the various products named above differ, and this sheds new light on the mechanism by which they are formed. We electrically arced graphite rods of high purity (99.99% C) in a helium atmosphere according to the general procedure for preparing fullerenes. Pyrolytic carbon on the shell of the cathode deposit has an isotopic ratio close to that of the graphite. This is strong evidence that the pyrolytic carbon is formed by a mechanism different from nanotube, nanopolyhedra, or soot formation. We conclude that nanotubes and nanopolyhedra, pyrolytic carbon, microtubes, and fullerene soot in the arcing process are formed by different mechanisms. The nanotubes and nanopolyhedra are produced preferentially from ions with lowest mass-to-charge ratio and atoms. It is probable that the nanotubes and nanopolyhedra are formed by direct electrode-electrode interchange of charged monoatomic ions. Fullerene soot is formed from species with higher mass-to-charge ratios which can escape the electromagnetic field of the arc. 18 refs., 1 tab.

• OSTI ID: 5257244
• Journal Information: Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 115:24; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
AROMATICS
CARBON
CARBON 12
CARBON 13
CARBON ISOTOPES
CURRENTS
ELECTRIC ARCS
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
ELECTRODES
ELEMENTAL MINERALS
ELEMENTS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FULLERENES
GRAPHITE
HYDROCARBONS
ISOTOPES
LIGHT NUCLEI
MASS SPECTROSCOPY
MINERALS
NONMETALS
NUCLEI
ORGANIC COMPOUNDS
POLYCYCLIC AROMATIC HYDROCARBONS
PYROLYTIC CARBON
SOOT
SPECTROSCOPY
STABLE ISOTOPES
SYNTHESIS