Diffusion Coefficients of C 60 and C 60 – in Benzonitrile and Dichloromethane Solutions Containing Tetrabutylammonium Perchlorate, Measured by Potential-step Chronoamperometry

The diffusion coefficients of C 60 in dichloromethane and benzonitrile solutions containing 0.1 M tetrabutylammonium perchlorate were determined by single potential-step chronoamperometry at small disk electrodes. The diffusion coefficients of C 60 were obtained by curve fitting of the chronoamperograms to a theoretical equation by Shoup and Szabo. The values were (1.4 ± 0.3)× 10 –9 and (4.1 ± 0.3)× 10 –10 m 2 s –1 , respectively (the errors are 95% confidence limits). The diffusion coefficients of C 60 – in these solutions were measured by double potential-step chronoamperometry. The ratios of the diffusion coefficients of C 60 to those of C 60 – were obtained from theoretical curves of the ratios of the current at the second potential step to the current at the first one. The values of the ratios were 1.2 ± 0.2 and 1.0 ± 0.3, respectively.