The electrochemical deposition of Pt nanoparticles on carbon nanotubes (CNTs) supports and their catalytic activities for
methanol electro-oxidation were investigated. Pt catalysts of 4~12 nm average crystalline size were grown on supports by
potential cycling methods. Electro-plating of 12 min time by potential cycling method was sufficient to obtain small
crystalline size 4.5 nm particles, showing a good electrochemical activity. The catalysts’ loading contents were enhanced by
increasing the deposition time. The crystalline sizes and morphology of the Pt/support catalysts were evaluated using X-ray
Diffraction (XRD) and Transmission Electron Microscopy (TEM). The electrochemical behaviors of the Pt/support catalysts
were investigated according to their characteristic current-potential curves in a methanol solution. In the result, the
electrochemical activity increased with increased plating time, reaching the maximum at 12 min, and then decreased. The
enhanced electroactivity for catalysts was correlated to the crystalline size and dispersion state of the catalysts.