Silica-supported Au–Cu alloy nanoparticles as an efficient catalyst for selective oxidation of alcohols

Silica-supported Au–Cu and Au–Ag alloy nanoparticles were synthesized, characterized, and tested for the aerobic oxidation of alcohols. The results showed that Au–Cu alloy catalyst exhibited good activity and selectivity to aldehydes for a variety of structurally diverse alcohols and a strong synergistic effect was found between Au and Cu. In contrast, Au–Ag alloy catalysts were less active and selective for the oxidation of alcohols although they have very similar particle sizes to the Au–Cu alloy catalysts. Besides the chemical compositions, the pretreatment conditions were found to affect significantly the catalytic performances, and the reduction treatment is necessary for obtaining a high activity and selectivity, suggesting Au–Cu alloy is the active phase. Moreover, the catalyst could be reused if only the catalyst after the reaction was subjected to reduction treatment.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (127 K)Download as PowerPoint slideHighlights► Au–Cu/SiO2 catalysts are highly active and selective for oxidation of alcohols. ► There is a strong synergistic effect between Au and Cu. ► Reduction pretreatment is necessary for a good performance.