The electrochemical performance of pure Pt and Pt-based alloy nanoparticle catalysts with various Pt, Ru and Mo concentrations is investigated. Pure Pt, Ru, and Mo are first deposited on multi-walled carbon nanotubes (MWCNTs) using a E-beam evaporator (MEP5000, SNTEK), and Pt-based alloy nanoparticles are subsequently formed on the MWCNTs via flash light irradiation. Several microscopic and spectroscopic techniques, including X-ray diffractometry, scanning electron microscopy, and Raman spectroscopy are employed to characterize the catalysts. Cyclic voltammetry experiments are also performed to measure the electrochemical reactions of the Pt-based alloy nanoparticle/MWCNT catalysts. To verify the experimental results, a computational simulation analysis is conducted using molecular dynamics and the application of density functional theory. From the experimental and analytical findings, it is concluded that the Pt-43-Ru-43-Mo-14/MWCNT structure exhibits the best electrochemical performance for the oxidation of methanol. (C) 2014 The Electrochemical Society. All rights reserved.