Pt-Au/MOx -CeO2 (M = Mn, Fe, Ti) catalysts for the co-oxidation of co and H2at room temperature

Abstract

A series of nanostructured Pt-Au/MOx -CeO2 (M = Mn, Fe, Ti) catalysts were prepared and their catalytic performance for the co-oxidation of carbon monoxide (CO) and hydrogen (H2 ) were evaluated at room temperature. The results showed that MOx promoted the CO oxidation of Pt-Au/CeO2 , but only the TiO2 could enhance co-oxidation of CO and H2 over Pt-Au/CeO2 . Related characterizations were conducted to clarify the promoting effect of MOx . Temperature-programmed reduction of hydrogen (H2 -TPR) and X-ray photoelectron spectroscopy (XPS) results suggested that MOx could improve the charge transfer from Au sites to CeO2 , resulting in a high concentration of Ce3+ and cationic Au species which benefits for the CO oxidation. In-situ diffuse reflectance infrared Fourier transform spectroscopy (In-situ DRIFTS) results indicated that TiO2 could facilitate the oxidation of H2 over the Pt-Au/TiO2 -CeO2 catalyst.