Electrodeposition of platinum-ruthenium nanoparticles on carbon nanotubes directly grown on carbon cloths for methanol oxidation

Dense carbon nanotubes (CNTs) were grown via a thermal chemical vapor deposition (CVD) process on titanium treated carbon cloths. Platinum-ruthenium (Pt-Ru) nanoparticles were then deposited on the CNT surfaces by potentiostatic electrodeposition in mixed sulfuric acid and ethylene glycol (EG) containing aqueous electrolytes. After the deposition process, the surface morphology of prepared specimens was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the electrochemical characteristics of the specimens were investigated by cyclic voltammetry (CV) in mixed sulfuric acid and methanol aqueous solutions saturated with nitrogen. Finely dispersed Pt-Ru nanoparticles were observed on the surfaces of the CNTs directly grown on carbon cloths. It was also observed that the performance of the Pt-Ru catalysts in terms of methanol oxidation efficiency and suppression of carbon monoxide adsorption would be influenced by the concentrations of sulfuric acid, EG, and Ru precursor salt during the electrodeposition processes.