Jump to main content
Jump to site search


Thermal reduction of ceria nanostructures on rhodium(111) and re-oxidation by CO2

Author affiliations

Abstract

The thermal reduction of cerium oxide nanostructures deposited on a rhodium(111) single crystal surface and the re-oxidation of the structures by exposure to CO2 were investigated. Two samples are compared: a rhodium surface covered to ≈60% by one to two O–Ce–O trilayer high islands and a surface covered to ≈65% by islands of four O–Ce–O trilayer thickness. Two main results stand out: (1) the thin islands reduce at a lower temperature (870–890 K) and very close to Ce2O3, while the thicker islands need higher temperature for reduction and only reduce to about CeO1.63 at a maximum temperature of 920 K. (2) Ceria is re-oxidized by CO2. The rhodium surface promotes the re-oxidation by splitting the CO2 and thus providing atomic oxygen. The process shows a clear temperature dependence. The maximum oxidation state of the oxide reached by re-oxidation with CO2 differs for the two samples, showing that the thinner structures require a higher temperature for re-oxidation with CO2. Adsorbed carbon species, potentially blocking reactive sites, desorb from both samples at the same temperature and cannot be the sole origin for the observed differences. Instead, an intrinsic property of the differently sized CeOx islands must be at the origin of the observed temperature dependence of the re-oxidation by CO2.

Graphical abstract: Thermal reduction of ceria nanostructures on rhodium(111) and re-oxidation by CO2

Back to tab navigation

Supplementary files

Publication details

The article was received on 07 Mar 2018, accepted on 29 Jun 2018 and first published on 03 Jul 2018


Article type: Paper
DOI: 10.1039/C8CP01505H
Citation: Phys. Chem. Chem. Phys., 2018, Advance Article
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    Thermal reduction of ceria nanostructures on rhodium(111) and re-oxidation by CO2

    A. Schaefer, B. Hagman, J. Höcker, U. Hejral, J. I. Flege and J. Gustafson, Phys. Chem. Chem. Phys., 2018, Advance Article , DOI: 10.1039/C8CP01505H

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements