Carbon nanotube (CNT) containing electrocatalysts, Pt/Sn/PMo12/CNT, Pt/Sn/CNT, and Pt/CNT, were prepared by a microwave-heated polyol process. The electrocatalysts were characterized by X-ray diffraction, energy dispersive spectroscopy, scanning and transmission electron microscopy, and cyclic voltarnmetry. We found that the addition of PMo12 can help Pt-Sn nanoparticles to disperse very uniformly on the outer walls of CNTs. The Pt/Sn/PMo12/CNT catalyst exhibited the lowest onset potential for electro-oxidation of adsorbed C intermediates, compared to the Pt/Sn/CNT and Pt/CNT catalysts. It also generated much higher current density for methanol oxidation at room temperature compared to Pt/Sn/CNT and Pt/CNT catalysts, which were prepared by the same method. (c) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.