Sun, BY (reprint author), Chinese Acad Sci, Inst High Energy Phys, Lab Biol Effects Nanomat & Nanosafety, Beijing 100049, Peoples R China.
C-121 and C-121/didodecyldimethylammonium bromide (DDAB) film modified electrodes have been constructed and their electrochemistry has been studied. In the acetonitrile solution containing 0.1 M tetrabutylammonium perchlorate. the C-121 films show three couples of relatively stable redox peaks corresponding to three two-electron transfer processes involving reduction of two fullerene units in the dimers. In an aqueous solution containing 0.1 M tetrabutylammonium bromide, the C-121 films display an irreversible reduction peak, whereas the C-121/DDAB films display two couples of quasi-reversible redox peaks with the splitting first peak, and the C-121/DDAB films have good reversibility and stability in the aqueous solution due to existence of DDAB. All of these experimental results indicate that voltammetric behaviors of the C-121 films are different from those of C-60 films due to different structures though C-121 is carbon-bridged C-60 dimer, and the common characteristics are that their electrochemical behaviors are dependent on the nature of solvent and cation of supporting electrolyte. Furthermore, electrocatalysis of H2O2 at the C-121/DDAB films was explored in the aqueous solution, which indicates that C-121 is a good electron-transfer mediator. (c) 2009 Elsevier B.V. All rights reserved.