Sub-stoichiometric titanium oxide-supported platinum electrocatalyst for polymer electrolyte fuel cells

Sub-stoichiometric titanium oxide, Ti4O7-supported Pt electrocatalysts for polymer electrolyte fuel cells (PEFCs) were prepared, and the electrochemical properties under PEFC operating conditions were examined. Platinum nanoparticles were deposited by a conventional impregnation method, and the applicability as an electrocatalyst was confirmed by cyclic voltammetry (CV). The onset potential of the corrosion current during the positive direction sweep of CV was much higher for Ti4O7 than for the Vulcan XC-72 carbon support, which indicates that Ti4O7 would be quite oxidation resistant under the actual PEFC operating conditions. Polarization measurements during single cell operation revealed that the Pt catalyst particles deposited on Ti4O7 showed equal specific activity for both the hydrogen oxidation reaction and the oxygen reduction reaction compared to a conventional carbon-supported Pt fuel cell catalyst.