FORMATION AND DETECTION OF FULLERENE METAL-COMPLEXES USING TIME-OF-FLIGHT SECONDARY-ION MASS-SPECTROMETRY

We have found that metal/fullerene adduct ions of the C60 and C70 fullerenes can be formed with silver, gold, rhodium, and palladium by argonion bombardment of fullerenes deposited on a metal substrate, with the use of a Time-of-Flight Secondary Ion Mass Spectrometer (TOF-SIMS). The bis and tris metal/fullerene adducts formed include: Ag(C60)2+, AgC60C70+, Ag(C70)2+, Ag(C60)3+, Ag(C60)2C70+, AgC60(C70)2+, and Rh(C60)2+. In addition,the monomeric adducts AgC60+, AgC70+, AuC60+, AuC70+, RhC60+, RhC70+, and PdC60+ also have been detected. Samples prepared with a raw soot extract gave higher yields of metal/fullerene adducts in TOF-SIMS than those prepared with purified fullerenes. This result may indicate the presence of a matrix component in the raw soot which enhances the formation of fullerene/metal adducts. Spectra obtained from the raw soot show peaks at every 24 daltons corresponding to even-numbered carbon clusters. These peaks occur as low as 600 daltons (C50) and as high as 3000 (C250).