The electrochemical properties of the major isomer of Dy@C₈₂[Dy@C₈₂(I)] films have been studied in organic and aqueous solutions. In acetonitrile solution, the electrochemical behavior of Dy@C₈₂(I) film is different from that of Dy@C₈₂(I) dissolved in organic solution. Large splittings between reduction and reoxidation waves for the first and the second electron-transfer reactions were observed. However, a pair of reversible oxidation and rereduction waves was obtained after the reoxidation of a reduced film, which is interpreted as the favorable structure after reduction of the film and no structural reorganization was needed. In aqueous solution, the electrochemical properties of Dy@C₈₂(I) film are similar with those of Dy@C₈₂(I) dissolved in organic solutions, where the first three reversible reduction and reoxidation waves and the first oxidation and rereduction waves were obtained. In water, Dy@C₈₂(I)^-, Dy@C₈₂(I)^2-, Dy@C₈₂(I)^3- and Dy@C₈₂(I)⁺ were found to be stable. The characteristic of this film was also uncovered by UV-Vis-NIR spectra and scanning electron microscopy (SEM), etc.

Key words: metallofullerene, Dy@C₈₂(I)film, electrochemistry