Monolithic Ag-Cu2O/Ti-foam for the gas phase oxidation of alcohols: Synergistic effect between Ag and Cu2O

The robust Ag-Cu2O/Ti-foam in the gas phase oxidation of alcohols is fabricated by impregnation and calcination method. The best catalyst is Ag-3-Cu2O-5/Ti-foam (3 wt% Ag, 5 wt% Cu), capable of oxidizing benzyl alcohol (95% benzyl alcohol conversion, 98% benzyl aldehyde selectivity) at low temperature of 260 °C. The synergistic effect between Ag and Cu2O in the high alcohol-oxidation performance effectively works in three aspects: Ag promotes the formation of Cu2O from Cu-species with other valences; Ag stabilizes the existence of Cu2O; Ag is beneficial in the dehydrogenation of Cu2O-H intermediates to drive the catalytic circle.