Some factors affecting the performance of anodic catalysts for direct methanol fuel cell

This research aims to increase the utilization of platinum-ruthenium alloy (Pt-Ru) catalysts and thus to lower the catalyst loading in anodes for methanol electrooxidation. The DMFC anodic catalysts, Pt-Ru/C, were prepared with different concentration of the reducing agent, pH values of the solution, and temperatures of reduction. Their performances were tested by cyclic voltammetry and potentiostatic polarization with a powder microelectrode from them in 0.5 mol/L CH₃OH and 0.5 mol/L H₂SO₄ solution. The size, its distribution and crystallin of the deposited catalysts were determined by means of high-resolution transmission electron microscopy and X-ray diffraction. The catalyst prepared with a solution of pH 8 at 801 showed the best catalytic performance for methanol electrooxidation. It had a more homogeneous distribution of Pt-Ru alloy in carbon. Its size is small, about 4nm. The catalyst performance was affected by the concentration of reducing agent, which should be small.