Surface reaction network of CO oxidation on CeO/Au(110) inverse model catalysts.

CeO/Au(110) inverse model catalysts were prepared and their activity toward the adsorption and co-adsorption of O, CO, CO and water was studied by means of X-ray photoelectron spectroscopy, low energy electron diffraction, thermal desorption spectra and temperature-programmed reaction spectra. The Au surface of CeO/Au(110) inverse model catalysts molecularly adsorbs CO, CO and water, and the polycrystalline CeO surface of CeO/Au(110) inverse model catalysts molecularly adsorbs O, and molecularly and reactively adsorbs CO, CO and water. By controllably preparing co-adsorbed surface species on CeO/Au(110) inverse model catalysts, we successfully identified various surface reaction pathways of CO oxidation to produce CO with different barriers both on the CeO surface and at the Au-CeO interface, including CO oxidation by various oxygen species, and water/hydroxyl group-involved CO oxidation. These results establish a surface reaction network of CO oxidation catalyzed by Au/CeO catalysts, greatly advancing the fundamental understandings of catalytic CO oxidation reactions.