Voltammetric studies on microcrystalline C_60 adhered to an electrode surface by solvent casting and mechanical transfer methods

摘要

Voltammetric studies on C_60 fullerene particles adhered to an electrode surface by solvent casting or mechanical transfer exhibit evidence of nucleation and growth controlled processes for the C_60~0/- and C_60~-/2 solid state when the modified electrode is in contact with acetonitrile solutions containing NBu_4~+ electrolyte. Although peak potentials and peak potentials and peak separation sare dependent on scan rate as well as the amount of deposit and temperature, potentials obtained using a zero-cur-rent extrapolation method are almost independent of all these parameters. These data enable reversible potentials of -816 and -1168 mV vs. Ag/Ag~+ to be obtained in acetonitrile (0.1 M NBu_4PE_6) respectively for the processes: C_60(solid) + NBu_4+(solution)+3~-<=> NBu_4 C_60(solid) and NBu_4C_60(solid)_NBu_~+ (solution)+e~- <=> (NBu_4)_2 C_60(solid). Images obtained by scanning electron microscopy reveal that both the crystalline and particle size is enhanced by 60 s of reductive electrolysis, with the detected (NBu_4)_2C_60 crystals being slightly larger than those of (NBu_4)_C_60. After a short period of potential cycling or controlled potential electrolysis, it is concluded that the data obtained by either method of surface adherence are almost indistinguishable, as are their morphologies.