The electrochemical behavior of a C-60/MWCNT (multi-walled carbon nanotube) film cast on GC electrode in acetonitrile solution was investigated. Repeated cyclic voltammetric scans transformed the precursor to a C-60-MWCNT composite film which exhibited reversible electron-transfer reactions and superpose the redox feature of the bare MWCNTs with monotonic charge injection over the whole potential range. This is in contrast to both C-60 film and peapods of C-60 inside carbon nanotubes but resembles the behavior of C-60 dissolved in organic solutions. The formation and structure of the C-60-MWCNT composite films were studied by UV-Vis, FT-IR, and TEM. (c) 2005 Elsevier B.V. All rights reserved.