PtCu/C Materials Doped with Different Amounts of Gold as the Catalysts of Oxygen Electroreduction and Methanol Electrooxidation

The effect of the amount of gold used as the dopant of PtCu nanoparticles on the structure of PtCuAu/Cu catalysts and their activity in the reactions of oxygen reduction and methanol electrooxidation is studied. The PtCuAu/C materials containing from 3 to 20% of gold are prepared by galvanic displacement of copper atoms by gold atoms on the surface of already prepared PtCu nanoparticles. The addition of 5 at % Au to the composition of nanoparticles doubles their activity in the methanol oxidation and increases their activity in the oxygen reduction by a factor of 1.7 as compared with the commercial Pt/C material JM40. This study confirms that multicomponent platinum-containing nanoparticles supported by a highly disperse carbon material and having gold atoms deposited on their surface show promise as the efficient catalysts for the methanol fuel cells. In contrast, the materials containing 10 at % Au and more are characterized by the presence of gold nanoparticles on the carbon support surface and exhibit the lower catalytic activity as compared with those containing less amounts of gold.