Characterization and reactivity of α-Al2O3-supported Pt-Co bimetallic catalysts

Abstract

Bimetallic Pt-Co and monometallic Pt and Co catalysts in as-prepared and reduced states were characterized by X-ray diffraction, temperature-programmed reduction, XPS and Farier transform infrared spectroscopy (FTIR). Temperature-programmed reduction and XPS results showed that the addition of platinum lowered the reduction temperature of cobalt oxides and simultaneously increased the amount of cobalt surface phase. The metallic Pt and Co in bimetallic Pt-Co catalysts was found to be highly dispersed in supports. In situ FTIR study of CO adsorption on catalysts confirmed that there was either strong interaction between metallic Pt and Co, or a Pt-Co bimetallic interphase was formed. The CO2 reforming of methane to synthesis gas was also investigated. Both Pt and Co in Pt-Co bimetallic catalysts exerted catalytic activity on CO2 reforming of methane. The coking was effectively inhibited over Pt-Co bimetallic catalysts, which was attributed to the formation of a Pt-Co bimetallic interphase and the increase of cobalt surface phase.