Abstract

Highly dispersed FeOx was impregnated onto CeO2 using the unique precursor Na/Fe-ethylenediaminetetraacetate (NaFeEDTA) at varying Fe surface density (0–1.5 Fe/nm2). These catalysts were used for NO reduction by CO and were compared to a more traditional Fe(NO3)3 precursor impregnated on Na-promoted CeO2. Extensive characterization and spectroscopic measurements showed that NaFeEDTA produced a narrower distribution of smaller, noncrystalline, surface FeOx species with excellent redox cyclability (Fe3+ ↔ Fe2+). The NaFeEDTA catalysts exhibited corresponding higher steady-state activity for NO reduction by CO. In situ X-ray absorption spectroscopy with simultaneous gas-phase monitoring indicated that NO conversion began concurrent with reduction of Fe and Ce, suggesting that NO reduction occurred at a reduced Fe–O–Ce interface site. These results illustrate a new synthesis–structure–activity relationship for NO reduction by CO over redox-cycling FeOx sites that may support future rational design of emission control catalysts without Pt-group metals or zeolites.

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 call

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.