The electrochemical corrosion behaviors of single-walled carbon nanotubes (SWNTs) and multi-walled carbon nanotubes (MWNTs) were investigated with potentiostatic oxidation at 1.2 V for 120 h. The surface oxygen contents of the two types of carbon nanotubes were analyzed by cyclic voltammograms (CV) and X-ray photoelectron spectroscopy (XPS). The increase in oxygen content on the SWNTs surface is higher than that on the MWNTs after 120 h oxidation. The results indicate that MWNTs exhibit higher electrochemical stability than SAINT, thus a good electrode material for PEMFC. (c) 2007 Elsevier B.V. All rights reserved.