화학공학소재연구정보센터
Journal of Physical Chemistry A, Vol.105, No.45, 10237-10245, 2001
Reactions of group V transition metal oxide cluster ions with ethane and ethylene
Reactions of mass-selected group V transition metal oxide cluster ions (VxOy+/-, NbxOy+/-, and TaxOy+/-) with ethane (C2H6) and ethylene (C2H4) were investigated. The major reaction channels observed during the reactions Of C-2 hydrocarbons with MxOy+ were association and oxygen transfer. The association channel, MxOyC2Hn+, where n = 4 or 6, was common to most of the group V transition metal oxide cluster cations examined. However, a reaction channel corresponding to the loss of an oxygen atom from the mass-selected metal oxide cluster, producing MxOy-1+l, was only observed during the reactions Of (V2O5)(n)(+), where n = 1, 2, or 3, with ethane and ethylene and during the reactions of ethylene with Nb2O5+. It is proposed that this reaction pathway is oxygen transfer from the mass-selected metal oxide cluster cation to the neutral hydrocarbon. This oxygen transfer channel is the major pathway observed during the course of reactions Of V2O5+, V4O10+, and V6O15+ with ethane and ethylene, but this reaction pathway is minor or nonexistent in the case of reactions of C2H6 and C2H4 with stoichiometrically equivalent niobium and tantalum oxide cluster cations. Additionally, the reactions of MxOy- with C-2 hydrocarbons were also examined. In contrast to the cation results, no reaction products were observed in studies of the interaction of group V transition metal oxide cluster anions with ethane and ethylene. The studies reveal that the identity of the metal, charge state, cluster stoichiometry, and geometric structure strongly influence the ability of the metal oxide cluster to transfer an oxygen atom to the neutral C-2 hydrocarbon.