Abstract
Automotive exhaust gases containing harmful gases, such as hydrocarbons, CO, and NOx, are purified on a Pd-loaded catalyst. Since the purification efficiency depends on the oxygen concentration in the automotive exhaust gas, a material with a high oxygen storage performance is also essential for effectively purifying automotive exhaust gases. The present study demonstrates that the purification of the exhaust gases under fluctuating oxygen concentration proceeds efficiently on Pd/Ca2AlMnO5+δ which exhibits high oxygen release and storage capacities. Pd/Ca2AlMnO5+δ maintained reduction of NO to N2 for a longer time compared to conventional Pd/CeO2-ZrO2, under oxidative conditions. From the results obtained by combining operando and static X-ray absorption fine structure (XAFS) spectra, the valence state of the Mn species in the catalyst support was readily changed in response to the oxygen concentration in the exhaust gas, rather than that of the Pd species. In other words, the redox properties of the Mn species in Pd/Ca2AlMnO5+δ concern the NO reduction behavior under fluctuating oxygen concentration.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
