Journal of Power Sources, Vol.218, 93-99, 2012
Promotion effect of TiO2 on catalytic activity and stability of Pt catalyst for electrooxidation of methanol
TiO2 and C are mixed up physically as hybrid support of Pt nanoparticles for methanol electrooxidation. The morphology and electrocatalytic properties of the as-obtained catalysts have been investigated by transmission electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, cyclic voltammetry and chronoamperometry. The catalytic activity and stability of Pt/TiO2-C catalyst are both improved markedly compared with that of Pt/C catalyst. The initial and final current of Pt/TiO2-C catalyst after 3600 s reactions for methanol oxidation is about 1.57 and 6 times as high as that of the Pt/C catalyst, respectively. The promotion effect of TiO2 on catalytic activity and stability for Pt/TiO2-C catalyst is investigated further by physical and electrochemical measurements. It is found that the addition of TiO2 could facilitate CO removal, hinder CO formation on Pt surface during methanol oxidation, and inhibit the agglomeration and corrosion of Pt particles, which can be resulted from the strong interaction between TiO2-C and Pt. (C) 2012 Elsevier B.V. All rights reserved.
Keywords:Titanium dioxide;Electrocatalysts;Metal-support interaction;Methanol electrooxidation;Fuel cells