Abstract
Despite enormous breakthroughs in our understanding of the reaction mechanism of the low-temperature CO oxidation on gold catalysts, in particular on Au/TiO2 and down to temperatures as low as −150 °C, there are still many contradictory proposals about the dominant reaction pathway. In this work, we will demonstrate that these discrepancies often originate from the rather different reaction conditions applied in numerous studies, most notably from different reaction temperatures. By combining temporal analysis of products reactor measurements with electron paramagnetic resonance spectroscopy, we will show that removal of TiO2 surface lattice oxygen from a Au/TiO2 catalyst upon exposure to CO (i) readily takes place at 120 °C, where it represents the active oxygen species for CO oxidation, (ii) is still possible at −20 °C, although much slower and to a much lower extent, and (iii) is completely inhibited at −90 °C. Consequences of these findings for our understanding of the dominant reaction pathway for the CO oxidation on Au/TiO2 catalysts, in particular its dependency on the reaction temperature, will be discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.