Reactive oxygen species in stoichiometric ceria: Bulk and low-index surfaces
2014 (English)In: Physica Status Solidi. Rapid Research Letters, ISSN 1862-6254, E-ISSN 1862-6270, Vol. 8, no 6, 600-604 p.Article in journal (Refereed) Published
We have calculated the stabilities of some reactive oxygen species (ROS) in stoichiometric bulk ceria and at the low-index (111) and (110)-surfaces, both in vacuum and in the presence of additional O-2 molecules. We find that the formation of intrinsic ROS, here oxygen superoxides (O-2(-)) and peroxides (O-2(2-)), is always endothermic at vacuum conditions and that the superoxide formation always leads to a higher formation energy than the peroxide formation. In the presence of additional O-2 molecules, intrinsic peroxide formation becomes exothermic at the (110)-surface in conjunction with the formation of extrinsic superoxide ions from adsorbed O-2 molecules. This coexistence of intrinsic and extrinsic ROS species is anticipated to be stable at low temperatures, and can be important for understanding the ROS chemistry for nanoceria used in low-temperature applications. [GRAPHICS] Oxygen-assisted reduction of the ceria(110) surface.
Place, publisher, year, edition, pages
2014. Vol. 8, no 6, 600-604 p.
ceria, reactive oxygen species, peroxides, superoxides, density functional theory calculations
IdentifiersURN: urn:nbn:se:uu:diva-229523DOI: 10.1002/pssr.201409099ISI: 000338021200023OAI: oai:DiVA.org:uu-229523DiVA: diva2:737192