In situ measurements under flow condition of the CO oxidation over supported gold nanoparticles

Abstract In situ FT-IR measurements for Au/TiO 2 and Au/Al 2 O 3 have been carried out under the flow condition of CO oxidation at atmospheric pressure. It has been found that the Au particles remain neutral (Au 0 ) in the presence of oxygen, while negatively charged particles (Au δ − ) is formed in the absence of oxygen, as a result of the charge transfer from the oxygen vacancies. Moisture did not significantly affect the adsorption states of CO over Au/TiO 2 and Au/Al 2 O 3 . Enhancement of the CO 2 production by moisture was observed over Au/Al 2 O 3 , which is accompanied by the decomposition of carbonate-like species by moisture.