Reactive oxygen species in stoichiometric ceria: Bulk and low‐index surfaces. Issue 6 (7th April 2014)

• Record Type: Journal Article
• Authors: Kullgren, Jolla; Hermansson, Kersti; Broqvist, Peter
• Is Part Of: Physica status solidi. Volume 8:Issue 6(2014:Jun.)
• Page Start: 600
• Page End: 604
• Publication Date: 2014-04-07
• Subjects: Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201409099
• Languages: English
• ISSNs: 1862-6254

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p> <boxed-text content-type="graphic" position="anchor" orientation="portrait"> <graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pghmhqjvtj" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /> </boxed-text> </p> <p>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<sub>2</sub> molecules. We find that the formation of intrinsic ROS, here oxygen superoxides (O<sub>2</sub><sup>–</sup>) and peroxides (O<sub>2</sub><sup>2–</sup>), 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<sub>2</sub> molecules, intrinsic peroxide formation becomes exothermic at the (110)‐surface in conjunction with the formation of extrinsic superoxide ions from adsorbed O<sub>2</sub> 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.</p> <p> <boxed-text content-type="graphic" position="anchor" orientation="portrait"> <graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pghmhqjvv2" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /> </boxed-text> </p> <p>Oxygen‐assisted reduction of the ceria(110) surface.</p> <p>(© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)</p> </abstract>