Preparation of Au–Pd/C catalysts by adsorption of metallic species in aqueous phase for selective oxidation

Au/C and Au–Pd/C catalysts were prepared on SX PLUS activated carbon using an adsorption method in which the precursor(s)–support interactions in aqueous solution were sought to be optimized. pH windows where maximum adsorption occurs were identified for four bimetallic cases, varying the incorporation order of the adsorbed metallic precursors and the oxidation state of the first metal introduced. All samples were characterized by XPS and SEM/EDXS, and the above-mentioned parameters were found to have an influence on the surface microstructure of the samples and on the activity of the bimetallic catalysts obtained. This preparation method leads to highly active catalysts for the selective oxidation of glucose, with the activity correlated with high surface Pd/C ratios.