Abstract: Carbon nanotubes (CNTs) supported Pt (Pt/CNTs) electrode was prepared with in situ ion-exchange method. X-ray photoelectron spectroscopy analysis and scanning electron microscope images showed that Pt nanoparticles were highly dispersed on the surface of electrochemically functionalized CNTs electrode, with Pt particle size of 4.0 nm as determined from X-ray diffraction analysis. The electrochemical surface area and the Pt utilization were enhanced in the ion-exchanged Pt/CNTs electrode, and the electrocatalytic activity for oxygen reduction was higher than the conventional electrode. This was attributed to the specific structure of the ion-exchanged Pt/CNTs electrode, in which almost all the Pt nanoparticles were deposited on the electrochemically active sites.

Key words: fuel cell, carbon nanotube, platinum, in situ ion-exchange, electrochemical surface area, electrochemical functionalization