Abstract

We have studied the nanostructural and nanochemical changes occurring in pure ceria (CeO2) and CeO2–zirconia (ZrO2) catalysts during reduction. The reduction is carried out in an environmental transmission electron microscope in dry H2 at 2 Torr up to 800°C. We use in-situ electron-energy-loss spectroscopy to follow changes in the oxidation state of the Ce at close to the nanometre level. Our measurements show that reduction may or may not be accompanied by significant structural rearrangements in the material. In pure CeO2 and the mixed oxide, the reduced form can be composed of both crystalline and amorphous material. Our measurements confirm the formation of a superlattice formed due to the ordering of O vacancies in CeO2 during reduction. The mixed oxide material shows that O vacancy ordering occurs only over 2–3 nm domains.

Full Text
Paper version not known

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.